TIMEEVENT DESCRIPTIONLOCATION

UNIVERSE
1,000,000,000,000 YBN
1) We are a tiny part of a universe made of an infinite amount of space, matter
and time.





  
995,000,000,000 YBN
11) There is no time I can identify as the start of the universe, the universe
has no beginning and no end; perhaps the same photons that have always been in
the universe continue to move in the space that has always been.





  
990,000,000,000 YBN
2) There is more space than matter.




  
980,000,000,000 YBN
3) All of the matter is made of particles of light humans have named "photons".
Photons are the base unit of all matter from the tiniest particles to the
largest galaxies.


The basic order of matter from smaller to largest is photons, electrons,
positrons, muons, protons, neutrons, atoms, molecules, living objects, planets,
stars, globular clusters, galaxies, galaxtic clusters.


  
960,000,000,001 YBN
5) Photons generally move 300 million meters every second in a line, but as
pieces of matter, can be slightly slowed from the force of gravity, and stop
for an instant when they collide.

Photons move 300 million meters every second in a
line but as pieces of matter their velocity changes slightly because of
gravity, and theoretically photons bounce off each other, at which time they
come to a complete stop relative to the rest of the universe for an instant
before bouncing and accelerating away from each other in the opposite
direction.



  
950,000,000,000 YBN
6) Matter is attracted to other matter and so photons form structures such as
protons, atoms, molecules, molecule groups (like all of life of earth),
planets, stars, galaxies, and clusters of galaxies.

Gravity is responsible for photons
forming Hydrogen, Hydrogen forming nebulas, nebulas forming stars, and stars
forming galaxies.




  
940,000,000,000 YBN
7) All of the hundreds of billions of galaxies we can see are only a tiny part
of the universe. Most of the galaxies in the universe we will never see
because they are too far away for even 1 particle of light from them to be
going in the exact direction of our tiny location, or are captured by atoms
between here and there.

One estimate has 70e21 (sextillion) stars in only the
universe we can see. That is 10 times more stars than grains of sand on all
the earth.




  
935,000,000,000 YBN
4) The patterns in the universe are clear. Photons form gas clouds of Hydrogen
and Helium, these gas clouds, called nebuli condense to form galaxies of stars.
The stars emit photons back out into the rest of the universe, where they
collect and form clouds again. Around each star are many planets and pieces of
matter. On many of those planets intelligent life evolves. This life moves
their stars out of spiral galaxies to form globular clusters, and ultimately to
transform spiral galaxies into elliptical galaxies that travel the universe
looking for more matter to fuel their movement.
It may very well be that stars at this
scale are photons, spiral galaxies charged particles, globular galaxies neutral
particles, and galactic clusters atoms at a much larger scale in an infinite
macro and micro scale.




  
930,000,000,000 YBN
8) That the frequency of photons from the most distant galaxies we can see have
a lower frequency may be due to the effects of gravitation and/or particle
collision in the large distance between source and observer.

EXPERIMENT: does sound
frequency actually get lower over large distances?


  
880,000,000,000 YBN
13) The Milky Way Galaxy forms, perhaps from a gas cloud that formed by
capturing matter in the form of light from other stars, from the remains of a
previously destroyed galaxy, or some combination of the two.





  
5,500,000,000 YBN
16) The yellow star earth will eventually orbit forms, perhaps in a nebula,
when matter in the nebula starts accumulating and rotating as a result of
gravity, or from the remains of an exploded star that condensed again under the
influence of gravity.

My opinion is that stars contain molten iron in their center,
similar to the earth. {check with supernova remnants} The density of the star
the earth rotates is similar to that of a liquid. The most popular theory to
explain how stars give off so many photons is that these photons exit as a
result of Hydrogen atomically fusing into Helium, and I want to add my opinion
that potentially the pressure of gravity simply separates atoms of Hydrogen and
helium into their source photons. Perhaps the reaction is similar to the
center of the earth where red hot liquid iron emits photons. We obviously do
not explain that red hot molten metal as being the result of nuclear fusion,
but yet it is clearly not oxygen combustion. Clearly there are many photons
exiting stars every second, and each star is losing large amounts of matter in
the form of photons. In addition, the most popular theory explains that most
atoms heavier than Hydrogen and no heavier than Iron are made in stars, and
atoms larger than iron can only be made in supernovae.

The current view
theorizes that the iron is made just before the supernova, in the gravitational
collapse, but I find a liquid iron core being there for the lifetime of every
star as a more logical explanation.


  
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22) Heavier atoms in the star system move closer to the center and lighter
atoms are sent farther out.





  
4,600,000,000 YBN
17) Planets form around star. Terrestrial planets are red hot, have surface of
melted rock, all lighter atoms float to the surface of the molten planets. All
the H2O from the first earth oceans and lakes is in the atmosphere in gas form.





  
4,600,000,000 YBN
30) Moon of earth is formed by 1 of 3 ways:
1) spherical planet collides with earth,
moon forms from remaining matter in ring around earth.
2) spherical planet is caught
in earth orbit
3) moon of earth forms naturally from original matter of star system
in orbit around earth.

The Moon orbiting 5 degrees from the axis of the Earth's orbit
implies that the Moon was captured, although 5% is not a particularly large
difference from the plane of the Earth's rotation. That the Moon orbits in the
same direction as the Earth is evidence in favor of the Moon forming around the
Earth.



  
4,571,000,000 YBN
31) Oldest meteorite yet found on earth 4,571 million years old.



  
4,530,000,000 YBN
33) Oldest Moon rock returned from Apollo missions (4.53 billions old).




  
4,500,000,000 YBN
24) Oldest meteor and moon (although no earth) rocks date from this time 4.5
billion years before now.





  

LIFE
4,500,000,000 YBN
50) Start Precambrian Eon, Hadean Era.



  
4,450,000,000 YBN
21) Planet earth cools, molten rock cools into thin crust, H2O condenses from
the atmosphere by raining, filling the lowest parts of land to make the first
earth oceans, lakes, and rivers.




  
4,404,000,000 YBN
34) Oldest "terrestrial" (not from meteorite) zircon yet found on earth, 4.404
billion years old, from Gneiss in West Australia, is evidence that the crust
and liquid water were on the surface of earth 4.4 billion years before now.




  
4,400,000,000 YBN
18) Amino acids, phosphates, and sugars, the components of living objects are
created on earth. These molecules are made in the oceans, fresh water, and or
atmosphere of earth (or other planets) by lightning, photons with ultraviolet
frequency from the star, or ocean floor volcanos.





  
4,395,000,000 YBN
19) How nucleic acids (polymers made of nucleotides), proteins (polymers made
of amino acids), carbohydrates (polymers made of sugars) and lipids (glycerol
attached to fatty acids) evolved is not clearly known.

Some proteins and nucleic acids have been formed in labs by using clay which
can dehydrate and which provides long linear crystal structures to build
proteins and nucleic acids on. Amino acids join together to form polypeptides
when an H2O molecule is formed from a Hydrogen (H) on 1 amino acid and a
hydroxyl (OH) on the second.

Are all proteins, carbohydrates, lipids and DNA the products of living objects?
Is RNA the only molecule of these that was made without the help of living
objects?

The most popular theory now has RNA (and potentially lipids) evolving first
before any living objects.

There is still a large amount of experiment, exploration and education that
needs to be done to understand the origins of living objects on planet earth.
My opinion is that as soon as there was liquid water on the earth, 4.4 billion
years before now, as zircon crystals show, the construction of living objects
started on earth.




  
4,390,000,000 YBN
25) RNA duplication evolves.

Perhaps RNA molecules, called "ribozymes" evolved which can make copies of RNA,
by connecting free floating nucleotides that match a nucleotide on the same or
a different RNA, without any proteins. But until such ribozyme RNA molecules
are found, the only molecule known to copy nucleic acids are proteins called
polymerases. If such ribozymes exist, then one of the first coded instructions
on the RNA molecule that was the ancestor of every living species, must have
been the code to make this ribozyme.

These early RNA molecules may have been protected
by liposomes (spheres of lipids).

This process of RNA (and then later DNA) duplication is the most basic aspect
of life on earth, and for all the diversity, the one common element of all life
is this constant process of DNA duplication, which will later evolve to include
cell division. This starts the unbroken thread of copying and division that
connects the earliest ancestor, some RNA molecule, to all life on earth that
has ever lived.




  
4,385,000,000 YBN
167) Protein assembly evolves with the creation of various Transfer RNA (tRNA)
molecules.

Random mutations in the copying (and perhaps even in the natural formation) of
RNA molecules probably created a number of the necessary tRNAs (transfer RNA,
an RNA molecule responsible for matching free floating amino acid molecules to
3 nucleotide sequences on other RNA molecules).

This would be a precellular protein assembly system, where tRNA (transfer RNA)
molecules can build polypeptide chains of amino acids by linking directly to
other RNA strands.

Part of each tRNA molecule bonds with a specific amino acid, and a 3 nucleotide
sequence from a different part of the tRNA molecule bonds with the opposite
matching 3 nucleotide sequence on an (m)RNA molecule.

Since there are tRNA molecules for each amino acid (although some tRNAs can
attach to more than one amino acid?), there must have been a slow accumulation
of various tRNA molecules for each of the 20 amino acids used in constructing
polypeptides in cells living now. Perhaps after the evolution of the first
tRNA, the first polypeptides were chains of all the same one amino acid. With
the evolution of a second tRNA polypeptides would have more variety because now
two amino acids would be available to build polypeptides.

This polypeptide assembly system may exist freely in water, or within a
liposome. This sytem builds many more proteins than would be built without
such a system. The mRNA with the code to make copier RNA, now also contains
the code to produce various tRNA molecules. These molecules function as a
unit, and proto-cell, with the rest of the mRNA initially containing random
codes for random proteins.

For the first time, RNA code represents a template for other RNA molecules, but
also a template for building proteins with the help of tRNA molecules.

There is some question of where the origin of the first cell took place, near
volcanos on the ocean floor, or in fresh water lakes and tidal pools near
volcanos on land, because unprotected nucleic acids cannot exist for much time
in the ocean because of Sodium and Chlorine.

What were the first amino acids connected
as proteins? Were the first proteins all made with the same amino acid?



  
4,380,000,000 YBN
168) Ribosomal RNA (rRNA) evolves. Ribosomal RNA moves down mRNA molecules
functioning as a platform for bringing the mRNA and tRNA molecules together to
assemble polypeptides (proteins).

This rRNA serves as an early ribosome; objects that serve as sites for building
polypeptides and are found in every cell. As time continues the ribosome will
grow to include two more RNA molecules, some protein molecules, and a second
half that will make polypeptide construction more efficient.

The rRNA serves the purpose of bringing amino acids close enough to bond with
each other to form polypeptides.

As an rRNA moves down an mRNA, tRNA molecules bond with the mRNA and on the
opposite side of the tRNA, a matching amino acid (separates? from the tRNA and)
attaches to a growing polypeptide chain.

Now the mRNA that is the ancestral/progenitor of all of life, contains the code
for the copier RNA, tRNAs, and the rRNA molecule. These nucleic acids function
as a unit, and proto-cell.





  
4,375,000,000 YBN
211) The first protein of real importance is built, an RNA polymerase. A
molecule that can more efficiently copy RNA.

The first protein of real importance
is evolved by RNA and assembled by the early ribosome, an RNA polymerase. A
molecule that can more efficiently copy RNA.




  
4,370,000,000 YBN
41) A ribonucleotide reductase protein is built by the early ribosome protein
making protocell. This protein changes ribonucleotides into
deoxyribonucleotides. This allows the first DNA molecule on earth to be
assembled.

Ribonucleotide reductase may be the molecule that allowed DNA to be the
template for the line of cells that survived to now.





  
4,365,000,000 YBN
212) A DNA polymerase protein evolves to copy DNA by assembling DNA nucleotides
from other DNA molecules.





  
4,360,000,000 YBN
166) An RNA molecule evolves that causes the early ribosome to create reverse
transcriptase, a protein that can assemble DNA molecules from an RNA molecule
template.

With this advance, a DNA molecule can be constructed that has all of the code
that was stored on the long evolved RNA molecule. DNA now serves as a more
stable template for making mRNA, each tRNA, rRNA, and the RNA and DNA
polymerases.

RNA polymerase proteins build RNA molecules using the new DNA template, that
still perform their original polypeptide building function together with the
tRNA and rRNA molecules, but are labeled "mRNA" (Messenger RNA) because they
move from DNA to ribosome.

Why DNA serves as the template for all cells and not mRNA is
not fully understood, but DNA is a more stable molecule than the single
stranded RNA. Perhaps the 2 legs of DNA serve some other important reasons,
for example, two legs may allow two processes to happen at one time.




  
4,355,000,000 YBN
20) The first cell membrane evolves around DNA, made of proteins. This
membrane holds water inside a cell. This is the first cell. rRNA comparison
shows that this is most likely a eubacterium.

DNA produces instructions for cytoplasm, the cytoplasm is assembled from
proteins made by the ribosome. For the first time, DNA and ribosomes are
building cell structure. The templates for each tRNA, rRNA, mRNA and DNA
polymerase proteins are already coded in a central strand of DNA. DNA
protected by cytoplasm is more likely to survive and copy. This cell is
heterotrophic and has no metabolism to produce ATP. Amino acids, nucleotides,
H2O, and other molecules enter and exit the cytoplasm only because of a
difference in concentration from inside and outside the cell (passive
transport) and represent the beginnings of the first digestive system. This
either happens in fresh water lakes or in salty oceans, perhaps near lava vents
on or under the ocean floor. As this line of DNA continues to make copies of
itself, all copies now have cytoplasm. The DNA is composed mainly of
instructions to assemble the nucleic acids and proteins needed to build
ribosomes, polymerases and cytoplasm.

This cell structure forms the basis of all future cells of every living object
on earth. These first cells are anaerobic (do not require free oxygen) and
heterotrophic, meaning that they do not make their own food: amino acids,
nucleotides, phosphates, and sugars. These bacteria depend on these molecules
and photons in the form of heat to reproduce and grow.

A system of division must evolve which attaches the original and newly
synthesized copy of DNA to the cytoplasm, so that as the cell grows, the two
copies of DNA can be separated and the first membraned cells can divide into
two cells. This is the beginning of the "binary fission" method of cell
division. Division of the cell begins with the division of the DNA
membrane-attachment site and separates by the growth of new cytoplasm.

DNA has 2
functions, 1) to be copied by the polymerase protein, 2) to serve as a code for
assembling proteins.
Two important evolutionary steps evolve: DNA duplication
in cytoplasm, and cell (DNA with cytoplasm) division.

The process of DNA duplication is probably similar if not the same process
using the same proteins that were used to duplicate DNA without cytoplasm.



  
4,350,000,001 YBN
26) Perhaps DNA that is connected in a circle allows the DNA polymerase to make
continuous copies of the cell.

In theory prokaryote cells do not deteroiate from the
effect of aging, but they do endure mutations (from photons with ultraviolet
frequency, for example), however, there are many other ways prokaryotes can be
destroyed (loss of water, physically damaged by nonliving objects, eaten by
other organisms, and other mechanisms).




  
4,345,000,000 YBN
195) Proteins that actively transport molecules into and out of the cytoplasm
(facilitative diffusion) evolve.




  
4,340,000,000 YBN
23) The first viruses are made either from bacteria, or are initially bacteria.
These cells depend on the DNA duplicating and protein producing systems of
other cells to reproduce themselves. Over time, more effective, and efficient
virus designs will survive.




  
4,335,000,000 YBN
28) Glycolysis evolves in the cytoplasm. Cells can now make ATP from glucose
and eventually other monosaccharides, the end product is pyruvate.

The glycolysis equation is:
C6H12O6 (glucose) + 2 NAD+ + 2 ADP + 2 P -----> 2
pyruvic acid, (CH3(C=O)COOH + 2 ATP + 2 NADH + 2 H+





  
4,330,000,000 YBN
44) Fermentation evolves in the cytoplasm. Cells (all anaerobic) can now make
more ATP and convert pyruvate (the final product of glycolysis) to lactate (an
ionized form of lactic acid).




  
4,325,000,000 YBN
213) A second kind of fermentation evolves in the cytoplasm. Cells (all
anaerobic) can now convert pyruvate (the final product of glycolysis) to
ethanol.




  
4,320,000,000 YBN
183) Cells evolve that make proteins that can assemble lipids.



  
4,315,000,000 YBN
196) Cells that use both proteins and metabolism (ATP) to transport molecules
into and out of the cytoplasm (active transport) evolve.




  
4,310,000,000 YBN
40) One of the first useful proteins to be created with an early precellular
protein production system must have been a protein (like RNA polymerase) that
can make copies of RNA from mRNA molecules. This protein may have outperformed
a ribozyme that was performing the copying function. Eventually mRNA that
coded for tRNA molecules and mRNA that coded for rRNA molecules merged to form
a template. Now the entire protein production system (the mRNA itself, tRNAs,
rRNAs, and the RNA polymerase) could be copied many times by the RNA polymerase
protein.

This is before cytoplasm or any cell wall has evolved. RNA and DNA copying
happens in water, the first cell has not evolved yet.





  
4,310,000,000 YBN
76) Pili, plasmids and conjugation evolves in prokaryotes. Now some
prokaryotes can exchange circular pieces of DNA (plasmids), through tubes
(pili). Conjugation may be the process that led to sex (cellular fusion) and
also the transition from a circle of DNA to chromosomes in eukaryotes, since
some protists (cilliates and some algae) reproduce sexually by conjugation.

Archaeal
flagellins are related to members of the type IV pilin/transport superfamily
widespread in bacteria.
In addition to pili and conjugation, proteins evolve that can
assist in splitting DNA and also proteins that assist in merging two strands of
DNA together, since some times the DNA in split and the new plasmid is
connected and the DNA circle is sown back together.



  
4,307,000,000 YBN
292) Prokaryote flagella evolve.
Perhaps pili evolved into flagella, flagella into
pili, or the two systems are unrelated.

Proteins in Archaebacteria flagella are related to pili in bacteria.

This may be the beginning of motility. Now for the first time, cells are not
completely controlled by surrounding matter, but can make limited choices about
their location.



  
4,305,000,000 YBN
64) Operons, sequences of DNA that allow certain proteins coded by DNA to not
be built, evolve. Proteins bind with these DNA sequences to stop RNA polymerase
from building mRNA molecules which would be translated into proteins. Operons
allow a bacterium to produce certain proteins only when necessary. Bacteria
before now can only build a constant stream of all proteins encoded in their
DNA.




  
4,304,500,000 YBN
322) Nitrogen fixation evolves in eubacteria.
Without bacteria that convert N2 into
nitrogen compounds, the supply of nitrogen necessary for much of life would be
seriously limited and would drastically slow evolution on earth.

Nitrogen fixation is
the process by which nitrogen is taken from its relatively inert molecular form
(N2) in the atmosphere and converted into nitrogen compounds useful for other
chemical processes (such as, notably, ammonia, nitrate and nitrogen dioxide).

Nitrogen fixation is performed naturally by a number of different prokaryotes,
including bacteria, and actinobacteria certain types of anaerobic bacteria.
Many higher plants, and some animals (termites), have formed associations with
these microorganisms.

The best-known are legumes (such as clover, beans, alfalfa and peanuts,)
which contain symbiotic bacteria called rhizobia within nodules in their root
systems, producing nitrogen compounds that help the plant to grow and compete
with other plants. When the plant dies, the nitrogen helps to fertilize the
soil. The great majority of legumes have this association, but a few genera
(e.g., Styphnolobium) do not.



  
4,304,000,000 YBN
287) Multicellularity in the form of filment growth evolves in prokaryotes.
Cyanobacteria
grow in filaments.

Unlike eukaryotes, there is no communication between cells in prokaryote
filments.




  
4,302,000,000 YBN
316) Cell differentiation in prokaryotes evolve. Heterocysts evolve in
cyanobacteria.

Heterocysts are specialized nitrogen-fixing cells formed by some filamentous
cyanobacteria during nitrogen starvation.

What cell differentiation is first is unknown,
perhaps cells that form spores, or cysts, or perhaps cell differentiation that
is observes in cyanobacterial filamentous cells.

Heterocysts are specialized nitrogen-fixing cells formed by some filamentous
cyanobacteria, such as Nostoc punctiforme and Anabaena sperica, during nitrogen
starvation. They fix nitrogen from dinitrogen (N2) in the air using the enzyme
nitrogenase, in order to provide the cells in the filament with nitrogen for
biosynthesis. Nitrogenase is inactivated by oxygen, so the heterocyst must
create a microanaerobic environment. The heterocysts' unique structure and
physiology requires a global change in gene expression. For example,
heterocysts:

* produce three additional cell walls, including one of glycolipid that
forms a hydrophobic barrier to oxygen
* produce nitrogenase and other proteins
involved in nitrogen fixation
* degrade photosystem II, which produces oxygen
* up
regulate glycolytic enzymes, which use up oxygen and provide energy for
nitrogenase
* produce proteins that scavenge any remaining oxygen

Cyanobacteria usually obtain a fixed carbon (carbohydrate) by photosynthesis.
The lack of photosystem II prevents heterocysts from photosynthesising, so the
vegetative cells provide them with carbohydrates, which is thought to be
sucrose. The fixed carbon and nitrogen sources are exchanged though channels
between the cells in the filament. Heterocysts maintain photosystem I, allowing
them to generate ATP by cyclic photophosphorylation.

Single heterocysts develop about every 9-15 cells, producing a one-dimensional
pattern along the filament. The interval between heterocysts remains
approximately constant even though the cells in the filament are dividing. The
bacterial filament can be seen as a multicellular organism with two distinct
yet interdependent cell types. Such behaviour is highly unusual in prokaryotes
and may have been the first example of multicellular patterning in evolution.
Once a heterocyst has formed, it cannot revert to a vegetative cell, so this
differentiation can be seen as a form of apoptosis. Certain heterocyst-forming
bacteria can differentiate into spore-like cells called akinetes or motile
cells called hormogonia, making them the most phenotyptically versatile of all
prokaryotes.

The mechanism of controlling heterocysts is thought to involve the diffusion of
an inhibitor of differentiation called PatS. Heterocyst formation is inhibited
in the presence of a fixed nitrogen source, such as ammonium or nitrate. The
bacteria may also enter a symbiotic relationship with certain plants. In such a
relationship, the bacteria do not respond to the availability of nitrogen, but
to signals produced by the plant. Up to 60% of the cells can become
heterocysts, providing fixed nitrogen to the plant in return for fixed carbon.

The cyanobacteria that form heterocysts are divided into the orders Nostocales
and Stigonematales, which form simple and branching filaments respectively.
Together they form a monophyletic group, with very low genetic variability.



  
4,300,000,000 YBN
58) First autotrophic cells, cells that can produce some if not all of their
own food (amino acids, nucleotides, sugars, phophates, lipids, and
carbohydrates), but require phosphorus, nitrogen, CO2, water and light in the
form of heat.

There are only 2 kinds of autotrophy: Lithotrophy and Photosynthesis. These
are lithotrophic cells that change inorganic (abiotic) molecules into organic
molecules. These cells are archaebacteria, called methanogens that perform the
reaction: 4H2 + CO2 -> CH4 + 2H2O. They convert CO2 into Methane. Methane is
better than CO2 for trapping heat, and could have contributed to heating the
earth.




  
4,295,000,000 YBN
49) First photosynthetic cells. These cells only have Photosystem I.
Photosynthesis Photosystem I evolves in early anaerobic prokaryote cells. One
of two photosythesis systems, photosystem I uses a pigment chlorophyll A,
absorbs photons in 700 nm wave lengths best, breaking the bond betwenn H2 and
S. They are anaerobic and perform the reaction: H2S (Hydrogen Sulfide) + CO2
+ light -> CH2O (Formaldehyde) + 2S.

Only 5 phyla of eubacteria can
photosynthesize.



  
4,290,000,000 YBN
43) Photosynthesis Photosystem II evolves in early prokaryote cells.
Photosystem 2 absorbs photons best at 680nm wavelengths, a higher frequency of
light than Photosystem I. These cells can break the strong Hydrogen bonds
between Hydrogen and Oxygen in water molecules (more abundant than Sulphur).
This system emits free Oxygen.

The simple equation of photosynthesis is: 6 H2O + 6 CO2 + photons = C6H12O6
(glucose) + 6O2. The detailed steps of photosynthesis are called the "Calvin
Cycle". Prokaryote cells can now produce their own glucose to store and be
converted to ATP by glycolysis and fermentation later.

This sytem is the main system responsible for producing the Oxygen now in the
air of earth.

Of the 5 phyla of eubacteria that can photosynthesize, only 1,
cyanobacteria, produces oxygen.



  
4,280,000,000 YBN
57) Cellular Respiration (also called the "Citric Acid Cycle", and the "Krebs
Cycle") evolves, probably in cyanobacteria, as a substitute for fermentaton, by
using oxygen to break down the products of glycolysis, pyruvic acid, to CO2 and
H2O, producing 18 more ATP molecules.
This is the first aerobic cell, a cell
that has an oxygen based metabolism. This cell uses oxygen to convert glucose
(and eventually other sugars and fats) into CO2, H2O and ATP. For example,
cells that oxidize glucose perform the reaction:
C6H12O6 + 6 O2 + 38 ADP + 38 phosphate
-> 6 CO2 + 6 H2O + 38 ATP
This reaction (with glycolysis) can produce up to 36 ATP
molecules. Cellular respiration is the opposite (although the specific
reactions differ) of photosynthesis which starts with H2O and CO2 and produces
glucose.

Steps are:
Glycolysis preparatory phase
Glycolysis pay-off phase
Oxidative carboxylation
Krebs cycle



  
4,260,000,000 YBN
27) DNA (or RNA) produces instructions for a cell wall. The cell wall only
protects bacteria and does not filter any molecules as the cytoplasm does.

is first
gram-negative cell wall?

1. Only contain a few layers of peptidoglycan -- the building block for
strong, rigid cell walls
2. Contain an outer membrane, external to the
peptidoglycan, called the lipopolysaccharide
3. The space between the layers of peptidoglycan
and the secondary cell membrane is called periplasmatic space
4. The S-layer is
directly attached to the outer membrane, rather than the peptidoglycan
5. Any flagella, if
present, have 4 supporting rings instead of two
6. No teichoic acids are
present"




  
4,250,000,000 YBN
29) There are many proteins and secondary processes in cells that are not fully
understood yet.





  
4,250,000,000 YBN
42) More prokaryote cell fossils need to be found, more DNA needs to be
sequenced, and more bacteria found and grown to fully understand when bacteria
parts evolved. For example:
flagella
plasmids
pili and "conjugation" the trade of pieces of plasmid DNA (this may be the
earliest form of sex {or syngamy})
changing into spores

When gram-stain positive cell walls evolved.

When the various shapes evolved:
spherical (coccus,cocci)
rod (bacillus,bacilli)
spiral (spirilla)
other:
short rods (coccobacilli).
commas (vibrii).
squares (rare)
stars (rare)
irregular (rare)

Which specific bacteria of the Archaea (if any) were first, which of the
Eubacteria and Cyanobacteria came next.

When the "Nitrogen Cycle" or "Nitrogen Fixing" evolved. Few cells can separate
N2 into N, (needed for nucleic acids?). The waste product urea is converted by
one bacteria to ammonia, a second bacteria converts the ammonia to N2.



  
4,250,000,000 YBN
77) There are many widely varying estimates of when the first Eubacteria and
Archaea evolved. Eubacteria and Archaea (also called Archaebacteria) are the
two major lines of Prokaryotes. Prokaryotes are the most primitive living
objects ever found. In contrast to the later evolved Eukaryotes, Prokaryotes
have a circle of DNA located in their cytoplasm (not chromosomes) and have no
nucleus. At least one genetic comparison shows Eubacteria and Archaea evolving
now.

After the full genomes of all living species are known, and understood we will
have more certainty about the history of evolution. Many genetic trees are
based on DNA genes (sequences of DNA that define nucleic acids or proteins).
In particular the genes for ribosomal RNA are thought to be very conserved over
time, although perhaps genes for reproduction, or cytoplasm, for example may
later prove to be more conserved over time.

Only when the full genomes of all living
species are known, and understood will we have strong certainty about the
history of evolution. Many genetic trees are based on DNA genes (sequences of
DNA that define nucleic acids or proteins), in particular ribosomal RNA which
is thought to be highly conserved over the eons of time. Ribosomal RNA may be
the best record of evolutionary history, but perhaps other genes, for example,
those involved with reproduction, or cytoplasm will prove to be more conserved
or better estimates of evolutionary history. For example, I think the method
of reproduction would be the most conserved, since that process is the most
necessary for survival, changes to those genes may stop continued existence,
where changes to rrna may not be as serious. In addition, the vast diversity
and change in reproductive method over time, should tell us that similar large
scale changes could have happened for rrna, cytoplasm, and indeed any part of a
cell.


These early Archaea and Eubacteria are "thermophile" bacteria, bacteria that
are found and grow best in hot water (80+ degrees Celsius). That genetic
evidence puts these prokaryotes as the oldest living prokaryotes is evidence
that the first prokaryotes on earth may have lived in hot water, perhaps near
thermal springs or near ocean floor volcanos. Perhaps the water on the early
earth was hot when these first prokaryotes evolved.

Archaea are similar to other
prokaryotes in most aspects of cell structure and metabolism. However, their
genetic transcription and translation are very similar to those of eukaryotes.


  
4,112,000,000 YBN
180) The Archaea Phylum, Euryarchaeotes evolve.
Genetic comparison shows the Archaea
Phylum, Euryarchaeotes evolving now.

The Euryarchaeota are a major group of Archaea. They include the methanogens,
which produce methane and are often found in intestines, the halobacteria,
which survive extreme concentrations of salt, and some extremely thermophilic
aerobes and anaerobes. They are separated from the other archaeans based mainly
on rRNA sequences.

Euryarchaeota may contain the most ancient DNA of any living object on earth.

PHYLUM
Euryarchaeota
CLASS Archaeoglobi
CLASS Halobacteria
CLASS Methanobacteria
CLASS Methanococci
CLASS Methanomicrobia
CLASS Methanopyri
CLASS Methanosarcinae
CLASS Thermococci
CLASS
Thermoplasmata


  
4,112,000,000 YBN
181) The Archaea Phylum, Crenarchaeotes evolves.
Genetic comparison shows Archaea
Phylum, Crenarchaeotes evolving now.

The phylum Crenarchaeota, commonly referred to as the crenarchaea, in the
domain Archaea, contains many extremely thermophilic and psychrophilic
organisms. They were originally separated from the other archaeons based on
rRNA sequences, since then physiological features, such as lack of histones
have supported this division. Until recently all cultured crenarchaea have been
thermophilic or hyperthermophilic organisms, some of which have the ability to
grow up to 113 degrees C. These organisms stain gram negative and are
morphologically diverse having rod, cocci, filamentous and unusually shaped
cells.

PHYLUM Crenarchaeotes
ORDER Caldisphaerales
ORDER Cenarchaeales
ORDER Desulfurococcales
ORDER Sulfolobales
ORDER Thermoproteales


  
4,030,000,000 YBN
35) Metamorphic rock, a Gneiss near Acasta and Great Slave Lake in the North
West territories of Canada dates from this time, 4030 million years before now.



  
3,977,000,000 YBN
193) Eubacteria "Hyperthermophiles" (Aquifex, Thermotoga, etc.) evolve now.
Genetic
comparison shows that Eubacteria "Hyperthermophiles" (Aquifex, Thermotoga,
etc.) evolve now.

This may be the living object with the most primitive DNA found on earth
(depending on the age of the archaea).
This group of eubacteria includes the
Phyla "Aquificae", "Thermodesulfobacteria", and "Thermotogae".

The Aquificae phylum is a diverse collection of bacteria that live in harsh
environmental settings. They have been found in hot springs, sulfur pools, and
thermal ocean vents. Members of the genus Aquifex, for example, are productive
in water between 85 to 95 °C. They are the dominant members of most
terrestrial neutral to alkaline hot springs above 60 degrees celsius. They are
autotrophs, and are the primary carbon fixers in these environments. They are
true bacteria (domain eubacteria) as opposed to the other inhabitants of
extreme environments, the Archaea.

Thermotoga are thermophile or hyperthermophile bacteria whose cell is wrapped
in an outer "toga" membrane. They metabolize carbohydrates. Species have
varying amounts of salt and oxygen tolerance. Thermotoga subterranea strain
SL1 was found in a 70°C deep continental oil reservoir in the East Paris
Basin, France. It is anaerobic and reduces cystine and thiosulfate to hydrogen
sulfide.



  
3,850,000,000 YBN
36) The oldest sediment on earth is also the oldest Banded Iron Formation, on
Akilia Island in Western Greenland. The oldest evidence for life on earth was
found in this rock by measuring the ratio of carbon 12 to carbon 13 in grains
of apatite (calcium phosphate) from this rock. Life uses the lighter Carbon-12
isotope and not Carbon-13 and so the ratio of carbon-12 to carbon-13 is
different from a nonliving source (calcium carbonate or limestone).




  
3,850,000,000 YBN
45) This marks the beginning of the Banded Iron Formation Rocks. These rocks
are sedimentary. They are made of iron rich chert (silicates, like SiO2).
These rocks have alternative bands of orange or yellow and black. In the red
parts the iron is oxydized (contains iron oxides, either hematite {Fe2O3 =
rust} or magnetite {Fe3O4]}).

These bands may have formed because photosynthetic bacteria (in stromatolites
found in shallow ocean shores, and purple bacteria floating in water) produce
oxygen from CO2 during photosynthesis. When the level of oxygen in the water
became too high, many bacteria died, and this cycle created the BIF. But BIF
also may form naturally when photons in uv frequencies split H2O into H2 and
O2. So perhaps the BIF bands represent cycles of more or less uv light
reaching the earth. Perhaps the alternating phenomenon is similar to
eukaryotic algal blooms. In any event, this free oxygen bonded with the many
tons of iron dissolved in the water to form insoluable iron oxide which then
fell to the ocean floor to form the orange layers of Banded Iron Formation.
How these alternating bands are made is not clear and has not yet been
duplicated in a lab.

This cycle of alternating orange and black bands will continue for 2 billion
years until 1,800 million years before now. This is the beginning of oxygen
production on earth, the atmosphere of earth still has only small amounts of
oxygen at this time.

It is amazing that people are still not certain what was the
cause of the oxygen, and the cycles that deposited the banded Iron Formation.



  
3,850,000,000 YBN
189) Fossils from Isua Banded iron formation, SW Greenland.


  
3,800,000,000 YBN
51) End Hadean Era, start Archean Era.



  
3,800,000,000 YBN
185) Isoprene compounds from Isua, Greenland Banded Iron Formation sediment are
evidence of the existence of Archaea.




  
3,760,000,000 YBN
186) Sulfur isotope ratios (34S/32S) and Hydrocarbon molecules (alkanes)
detected in 3760 billion year old Isua Banded Iron Formation, indicate the
possibility of photosynthetic sulfate reducing bacteria (Archaea, for example
Sulpholobus) and Cyanobacteria living at that time.




  
3,700,000,000 YBN
184) Amount of Uranium isotope measured in Isua, Greenland Banded Iron
Formation evidence of prokaryote Oxygen photosynthesis.




  
3,700,000,000 YBN
215) C13/C12 ratio of 3700+ MYO sediment in Australia shown to be consistent
with planktonic photosynthesizing organisms.



  
3,566,000,000 YBN
78) Genetic comparison shows Archaebacteria (Archaea) Phylum, Korarchaeotes
evolving now.



  
3,500,000,000 YBN
37) The oldest fossil evidence of life yet found. Stromatolites made by
photosynthetic bacteria found in both Warrawoona, Western Australia, and Fig
Tree Group, South Africa.




  
3,500,000,000 YBN
39) Oldest fossils of an organism, thought to be cyanobacteria, found in 3,500
Million Year old chert from South Africa and 3,465 Million year old Apex chert
of north-western Australia.

Oldest fossils of an organism, thought to be cyanobacteria,
found in 3,500 Million Year old chert from South Africa and 3,465 Million year
old Apex chert of the Pilbara Supergroup, Warrawoona Group, northwestern
Western Australia.

Some people argue that these are not fossils of bacteria but abiotic material.
Most genetic timelines put the origin of cyanobacteria much later around
2,700mybn.

Cyanobacteria evolved multicellularity where cellular differentiation occurs.

  
3,500,000,000 YBN
289) Some people think the origin of eukaryotes happened here at 3.5 bybn.

  
3,470,000,000 YBN
182) Sulphate fossil molecular marker evidence of moderate thermophile sulphur
reducing prokaryotes from North Pole, Australia.




  
3,470,000,000 YBN
216) Evidence of sulphate reduction by bacteria.



  
3,430,000,000 YBN
833) Stromatolites made by photosynthetic bacteria found in Pilbara Craton,
Australia.

Strelley Pool Chert


  
3,416,000,000 YBN
218) Fossil and molecular evidence of photosynthetic, probably anoxygenic,
bacteria that lived in mats in the ocean date to this time.




  
3,400,000,000 YBN
190) Fossils from Kromberg Formation, Swaziland System, South Africa.


  
3,260,000,000 YBN
71) Budding evolves in prokayotes. Different from binary division, where a cell
is split in half, in budding, a new complete cell is made in the original cell,
and the new cell bursts through the cell wall, the original cell wall must then
be repaired.

Budding is the only other method of reproduction known in prokaryotes
besides binary fission.
The only major difference between prokaryote budding
and binary division are that one or more new cells are completely formed inside
the original cell, where in binary division part of the original cell wall is
used to make the new cell.

In budding, a complete new cell is synthesized from a DNA template, where in
binary division only the DNA is duplicated and more cytoplasm and cell wall is
synthesized. So, budding preserves organelles made by the main DNA template
that cannot duplicate themselves and would not get duplicated or synthesized in
binary division, for example, flagella.

Although it is very unlikely, the possibility
does exist that prokaryote budding evolved from a eukaryote that lost it's
nucleus.


  
3,250,000,000 YBN
191) Fossils from Swartkoppie chert, South Africa are oldest evidence of
procaryotes that reproduce by budding and not binary fission.




  
3,235,000,000 YBN
68) Thermophilic prokaryote fossils found in 3235 million year old deep-sea
volcanogenic massive sulphide deposits from the Pilbara Craton of Australia may
be oldest Archaea fossils.




  
2,923,000,000 YBN
178) Eubacteria Phylum Firmicutes (low G+C {Guanine and Cytosine count} Gram
positive) evolve.

Genetic comparison shows Eubacteria Phylum Firmicutes (low G+C
{Guanine and Cytosine count} Gram positive) evolving here.

Firmicutes include the Classes: Bacillus (anthrax), Listeria, Mollicutes, and
Stephylococcus.
Firmicutes may be the first rod shaped bacteria, and first bacteria to have a
gram positive cell wall.
The peptidoglycan layer is thicker in Gram-positive bacteria
(20 to 80 nm) than in Gram-negative bacteria (7 to 8 nm)
Firmicultes form
endospores, and is the only phlyum of bacteria that evolved the ability to
build endospores.

The Firmicutes are a division of bacteria, most of which have
Gram-positive stains. A few, the Mollicutes or mycoplasmas, lack cell walls
altogether and so do not respond to Gram staining, but still lack the second
membrane found in other Gram-negative forms. Originally the Firmicutes were
taken to include all Gram-positive bacteria, but more recently they tend to be
restricted to a core group of related forms, called the low G+C group in
contrast to the Actinobacteria. They have round cells, called cocci (singular
coccus), or rod-shaped forms.

Many Firmicutes produce endospores, which are resistant to desiccation and can
survive extreme conditions. They are found in various environments, and some
notable pathogens. Those in one family, the heliobacteria, produce energy
through photosynthesis.


Firmicutes include:
CLASS Bacilli (rod shaped)
ORDER Bacillales (anthrax)
ORDER Lactobacillales
CLASS Clostridia
ORDER
Clostridiales
ORDER Halanaerobiales
ORDER Thermoanaerobacteriales
CLASS Mollicutes
ORDER Mycoplasmatales
ORDER Entomoplasmatales
ORDER Anaeroplasmatales
ORDER Acholeplasmatales


  
2,920,000,000 YBN
288) Eubacteria firmicutes evolve the abililty to form endpospores.
An endospore is any
spore that is produced within an organism (usually a bacterium). Most bacterium
produce only one spore, as this is not a reproduction process. This is in
contrast to exospores, which are rather produced by growth or budding. The
primary function of most endospores is to ensure the survival of a colony
through periods of environmental stress. Endospores are therefore resistant to
desiccation, temperature, starvation, ultraviolet and gamma radiation, and
chemical disinfectants.

One of the great questions of this time is: "what is the process behind cell
differentiation and cell growth?" How is each stage initiated and stopped?
There are a number of theories. One theory presumes the entire DNA strand is
accessible at all times. In this view operons are used sequentially, while
many proteins are supressed, some operons are active, which results in one set
of proteins developing the cell, at some point, the first group of operons are
inhibited and a different operon (or set of operons) is turned on, signalling a
new set of proteins to be built which effects the growth and shape of the cell.
An abundance of a first stage protein might initiate the second stage. A
second theory is that DNA is read like a computer program with some proteins
moving along the DNA strand, one part at a time. In this way, one portion of
the DNA may reflect one life stage, while the next portion represents the next
(and perhaps very different) life stage.

The endospore-forming bacteria belong to the Firmicutes.


  
2,800,000,000 YBN
177) Genetic comparison shows the ancestor of all Proteobacteria (Rickettsia
{mitochondria}, gonorrhoea, Salmonella, E coli) evolving now.

Proteobacteria
include 5 Classes:
CLASS Alpha Proteobacteria (Rickettsia Prowazekii
{mitochondria/typhus})
CLASS Beta Proteobacteria (Neisseria gonorrhoeae {gonorrhoea})
CLASS Gamma Proteobacteria
(Salmonella and Escherichia coli.)
CLASS Delta Proteobacteria
CLASS Epsilon Proteobacteria

The Proteobacteria are a major group of bacteria. They include a wide variety
of pathogens, such as Escherichia, Salmonella, Vibrio, Helicobacter, and many
other notable genera. Others are free-living, and include many of the bacteria
responsible for nitrogen fixation. The group is defined primarily in terms of
ribosomal RNA (rRNA) sequences, and is named for the Greek god Proteus, who
could change his shape, because of the great diversity of forms found in it.

All Proteobacteria are Gram-negative, with an outer membrane mainly composed of
lipopolysaccharides. Many move about using flagella, but some are non-motile or
rely on bacterial gliding. The last include the myxobacteria, a unique group of
bacteria that can aggregate to form multicellular fruiting bodies. There is
also a wide variety in the types of metabolism. Most members are facultatively
or obligately anaerobic and heterotrophic, but there are numerous exceptions. A
variety of genera, which are not closely related, can photosynthesize. These
are called purple bacteria, referring to their mostly reddish pigmentation.

The delta-proteobacteria Myxobacteria is capable of colonial multicellularity
and some view as possibly being the bacteria that formed the cytoplasm in
eukaryotes.

CLASS Alpha Proteobacteria (Rickettsia Prowazekii {mitochondria/typhus})
CLASS Beta Proteobacteria
(Neisseria gonorrhoeae {gonorrhoea})
CLASS Gamma Proteobacteria (Salmonella, Escherichia
coli., fireblight {Erwinia amylovora}, one form of dysentery {Shigella
dysenteriae}, Legionaires' disease {Legionella pneumophilia}, Haemophilus
influenzae {first free living organism to have entire genome sequenced},
Pseudomonas, the largest known bacteria {Thiomargarita namibiensis}, Cholera
{Vibrio cholerae})
The number of individual E. coli bacteria in the feces that one human
passes in one day averages between 100 billion and 10 trillion.
CLASS Delta
Proteobacteria (Bdellovibrio {parasite on other bacteria}, Geobacter {can
oxydize uranium, may be used as battery that runs on waste}, myxobacteria {form
multicellular bodies that make spores, have large genome}
CLASS Epsilon Proteobacteria
(Helicobacter {spiral bacteria})


  
2,784,000,000 YBN
176) Genetic comparison shows Eubacteria Phylum, Planctomycetes
(Planctobacteria) evolving now.

Planctomycetes are a possible ancestor of all
eukaryotes because the circle of DNA can sometimes be enclosed in a double
membrane.
Planctomycetes is a small phylum with only 4 Genera, require oxygen for growth
(obligately aerobic), are found in fresh and salt water. They reproduce by
budding. They have holdfast (stalk) at the nonreproductive end that helps them
to attach to each other during budding.

The life cycle involves alternation between sessile cells and flagellated
swarmer cells. The sessile cells bud to form the flagellated swarmer cells
which swim for a while before settling down to attach and begin reproduction.

It is also possible, although unlikely, that planctomycetes are descended from
a very early eukaryote that lost the nucleus but retained the cytoplasmic DNA,
since budding may have evolved as a method to duplicate a eukaryote cell from
the nucleus. (ok this is out there...maybe t3)

The organisms belonging to this
group lack murein in their cell wall Murein is an important heteropolymer
present in most bacterial cell walls that serves as a protective component in
the cell wall skeleton. Instead their walls are made up of glycoprotein rich in
glutamate. Planctomycetes have internal structures that are more complex than
would be typically expected in prokaryotes. While they don't have a nucleus in
the eukaryotic sense, the nuclear material can sometimes be enclosed in a
double membrane. In addition to this nucleoid, there are two other
membrane-separated compartments; the pirrellulosome or riboplasm, which
contains the ribosome and related proteins, and the ribosome-free paryphoplasm.


  
2,784,000,000 YBN
179) Genetic comparison shows Eubacteria Phylum, Actinobacteria (high G+C, Gram
positive) evolving now.

Actinobacteria have 5 Orders:
ORDER Acidimicrobiales
ORDER Actinobacteriales
ORDER Coriobacteriales
ORDER
Rubrobacteriales
ORDER Sphaerobacteriales

Actinobacteria include the causes of tuberculosis (Mycobacteria tuberculosis)
and leprosy (Mycobacteria leprae).

The Actinobacteria or Actinomycetes are a group of Gram-positive bacteria. Most
are found in the soil, and they include some of the most common soil life,
playing an important role in decomposition of organic materials, such as
cellulose and chitin. This replenishes the supply of nutrients in the soil and
is an important part of humus formation. Other Actinobacteria inhabit plants
and animals, including a few pathogens, such as Mycobacterium.

Some Actinobacteria form
braching filaments, which somewhat resemble the mycelia of the unrelated fungi,
among which they were originally classified under the older name Actinomycetes.
Most members are aerobic, but a few, such as Actinomyces israelii, can grow
under anaerobic conditions. Unlike the Firmicutes, the other main group of
Gram-positive bacteria, they have DNA with a high GC-content {guanine-cytosine
content} and some Actinomycetes species produce external spores.

Mycobacterium bovis (the bacterium responsible for bovine TB) in particular has
been estimated to be responsible, for the period of the first half of the 20th
century, for more losses among farm animals than all other infectious diseases
combined. Infection occurs if the bacterium is ingested.

Actinobacteria are unsurpassed in their ability to produce many compounds that
have pharmaceutically useful properties. In 1940 Selman Waksman discovered that
the soil bacteria he was studying made actinomycin, a discovery which granted
him a Nobel Prize. Since then hundreds of naturally occurring antibiotics have
been discovered in these terrestrial microorganisms, especially from the genus
Streptomyces.

When M.leprae was discovered by G.A. Hansen in 1873, it was the first bacterium
to be identified as causing disease in man. Although Leprosy is contagious, it
is not widespread because 95% of the population have immune systems able to
cope with the bacteria.


  
2,775,000,000 YBN
174) Genetic comparison shows Eubacteria Phylum, Spirochaetes (Syphilis, Lyme
disease) evolving now.

Includes leptospirosis (leptospira), Lyme disease (Borrelia
burgdorferi), and Syphilis (Treponema pallidum).
Spirochaetes only have one order:
ORDER
Spirochaetales

This is when the first spiral shaped bacteria evolve.

The spirochaetes (or spirochetes) are a phylum of distinctive bacteria, which
have long, helically coiled cells. They are distinguished by the presence of
flagella running lengthwise between the cell membrane and cell wall, called
axial filaments. These cause a twisting motion which allows the spirochaete to
move about. Most spirochaetes are free-living and anaerobic, but there are
numerous exceptions.

Spirochaetes only have one order:
ORDER Spirochaetales
and 3 families.


  
2,775,000,000 YBN
175) Genetic comparison shows Eubacteria Phyla Bacteroidetes and Chlorobi
(green sulphur bacteria) evolving now.

PHYLUM Bacteroidetes
CLASS Bacteroides
ORDER Bacteroidales
CLASS
Flavobacteria
ORDER Flavobacteriales
CLASS Sphingobacteria
ORDER Sphingobacteriales

PHLYUM Chlorobi (Green sulphur)
CLASS Chlorobia
ORDER Chlorobiales


The phylum Bacteroidetes is composed of three large groups of bacteria. By far,
more is written about and known about the Bacteroides class, than the other
two, the Flavobacteria and the Sphingobacteria classes. They are related by the
similarity in the composition of the small 16S subunit of their ribosomes.
Members of the bacteroides class are human commensals (they benefit but humans
receive no effect) and sometimes pathogens. Members of the other two classes
are rarely pathogenic to humans.

Chlorobi are the "green sulphur bacteria", are a family of phototrophic
(photosynthesizing) bacteria. Green sulfur bacteria are generally nonmotile
(one species has a flagellum), and come in spheres, rods, and spirals. Their
environment must be oxygen-free, and they need light to grow. They engage in
photosynthesis, using bacteriochlorophylls c, d, and e in vesicles called
chlorosomes attached to the membrane. They use sulfide ions as electron donor,
and in the process the sulfide gets oxidized, producing globules of elemental
sulfur outside the cell, which may then be further oxidized. (By contrast, the
photosynthesis in plants uses water as electron donor and produces oxygen.)

A species of green sulfur bacteria has been found living near a black smoker
off the coast of Mexico at a depth of 2,500 meters beneath the surface of the
Pacific Ocean. At this depth, the bacteria, designated GSB1, lives off the dim
glow of the thermal vent since no sunlight can penetrate to that depth.



  
2,775,000,000 YBN
217) Genetic comparison shows Eubacteria Phyla Chlamydiae and Verrucomicrobia
evolving now.

Chlamydiae includes (clamydia, trachoma {Chlamydia trachomatis}, a
form of pneumonia {Chlamydophila pneumoniae}, psittacosis {Chlamydophila
psittaci}.

CLASS Chlamydiae
ORDER Chlamydiales

PHYLA Verrucomicrobia
ORDER Verrucomicrobiales

The Chlamydiae are a group of bacteria, all of which are intracellular
parasites of eukaryotic cells. Most described species infect mammals and birds,
but some have been found in other hosts, such as amoebae.
Chlamydiae have a life-cycle
involving two distinct forms. Infection takes place by means of elementary
bodies (EB), which are metabolically inactive. These are taken up within a
cellular vacuole, where they grow into larger reticulate bodies (RB), which
reproduce. Ultimately new elementary bodies are produced and expelled from the
cell.

Verrucomicrobia is a recently described phylum of bacteria. This phylum
contains only a few described species (Verrucomicrobia spinosum, is an example,
the phylum is named after this). The species identified have been isolated from
fresh water and soil environments and human feces. A number of as-yet
uncultivated species have been identified in association with eukaryotic hosts
including extrusive explosive ectosymbionts of protists and endosymbionts of
nematodes residing in their gametes.

Evidence suggests that verrucomicrobia are abundant within the environment, and
important (especially to soil cultures). This phylum is considered to have two
sister phyla Chlamydiae and Lentisphaera.

There are three main species of chlamydiae that
infect humans:

* Chlamydia trachomatis, which causes the eye-disease trachoma and the
sexually transmitted infection chlamydia;
* Chlamydophila pneumoniae, which causes a
form of pneumonia;
* Chlamydophila psittaci, which causes psittacosis.


  
2,760,000,000 YBN
80) Endocytosis, a process where the cell membrane folds around some molecules
to form a spherical vesicle which enters the cytoplasm, and exocytosis, the
opposite process, where a vesicle combines with a call membrane to empty
molecules outside a cell both evolve in an early eukaryote cell.

Eukaryote cells can now swallow bacteria (phagocytosis) and liquid
(pinocytosis). The cells can then (heterotrophically) use the molecules
injested (for example a bacterium) for copying and to make ATP. This is the
first time one cell can eat a different living cell.

How similar endocytosis is to
conjugation is unknown at this time.



  
2,750,000,000 YBN
207) Cytoskeleton evolves in eukaryote cytoplasm.
One theory is that the cytoskeleton
formed from the eukaryote flagella (cilia, undulipodia) tubules.
Cytoskeleton is a
single body with the endoplasmic reticulum and nuclear membrane?



  
2,725,000,000 YBN
60) First eukaryotic cell evolves. This cell has a nucleus, with either single
strands or a circle of DNA inside. This is a single anaerobic cell. This is
the first protist.

This cell evolves either by:
1) two or more bacteria joined, one with flagella
(perhaps a eubacteria) formed the nucleus, a second formed the cytoplasm
outside the nucleus, eventually the code to build the entire cell including the
instructions to build the symbiotic captured bacteria was included in the new
nucleus,
2) the nucleus formed as part of the cytoplasm lattice, perhaps the
outer wall folded in on itself creating a double membrane, or a membrane grew
around the DNA (for example like planctobacteria) which provided more
protection for the DNA from the movement and digestive activities of cytoplasm
now without a rigid cell wall,
3) a bacteria with flagella that grew cytoplasm
and a secondary cell wall outside the original cell wall,
4) a virus,
5) a DNA
strand from conjugation with a different prokaryote stored in a vesicle.

There are key features that are different from eukaryotes and prokaryotes:
1) Eukaryotes
have a nucleus, prokaryotes do not.
2) DNA in eukaryotes is in the form of
chromosomes, in prokaryotes the DNA is in a circle.
3) Eukaryotes can do endocytosis,
fold their cell membrane around some external object and injest the object,
prokaryotes can not.
4) Eukaryotes have a membrane lattice of proteins, actin and
myacin, prokaryotes do not.
5) Eukaryotes have an endoplasmic reticulum and golgi
body.
6) Eukaryotes reproduce asexually by dual binary division (both nucleus and
cell divide by binary division), budding, or mitosis, prokaryotes reproduce by
budding or binary division.

If the nucleus is an engulfed prokaryote, this cell inherits the processes of
nuclear DNA duplication and nucleus division (karyokinesis) from prokaryote
binary division. Initially, both the nucleus and cell divide by binary
division.

Support for the nucleus forming from a prokaryote is that chromosomes in
parabasalia and dinoflagellates remain permanently anchored to the nuclear
membrane (envelope?) by the kinetochores, the same way prokaryote DNA anchors
to the cell membrane (wall?) during cell division.

A theory of an archaebacteria (perhaps an eocyte) forming the first eukaryote
nucleus and a gram-negative eubacteria forming the cytoplasm of the first
eukaryote is supported by genetic evidence.

This cell reproduces asexually by either binary fission (both nucleus and
cytoplasm) or budding, or sexually by conjugation or both cell and nuclei fully
merging.

If this cell has chromosomes, this is the first (haploid) organism with
chromosomes.

Perhaps a sperm-like flagellated prokaryote merged with an ovum-like prokaryote
from the same or a different species, perhaps by the ovum opening a pilus and
the sperm-like cell entering the pilus, and once inside opening a pilus through
which the DNA from the two cells could merge. Many diplomonads look like sperm
cells stuck in an ovum, with the still flagellated sperm forming the nucleus,
and some diplomonads, for example, the oxymonad, Saccinobaculus reproduce
sexually.

An important evolutionary step had to evolve here, and that is the evolution of
the prokaryote binary division system: 1) duplicating DNA in the cytoplasm, 2)
separating the two copies of DNA, and 3) the division of cytoplasm into two
cells to an adapted process of eukaryote cell division: 1) duplicating DNA in
the nucleus, 2) separating the DNA in the nucleus, 3) dividing the nucleus into
two nuclei, 4) separating the two nuclei, and then 5) dividing the cytoplasm
into two cells.

It appears in early eukaryote nuclei (as seen in closed mitosis, where the
nuclear membrane persistes through mitosis) that the nuclei divide by a process
similar to binary division (as opposed to budding), which adds to the support
for the first nucleus being a prokaryote and continuing to divide by binary
division.

Most people accept that the centrioles from which grow the microtubule spindles
that pull apart chromosomes in mitosis, evolved from the base pairs which
originally were, and on some species still are, connected to a cilium.

Perhaps there are some eukaryote nuclei that duplicate by budding, although
this has never been found to my knowledge. If ever found, that would imply
that budding evolved before the first eukaryote, but could have possibly
evolved after by simply dropping the instructions to copy anything other than
the nucleus. Binary cell division in the most basic form only synthesizes more
cytoplasm and cell wall, where budding reproduces the entire body plan of a
cell (or nucleus in this case).

evidence for prokaryote=eukaryote nucleus
1) flagella
connected to nucleus of metamonads.
a) flagella hints that nucleus prokaryote may have
been a male gamete (and the cytoplasm the female gamete).
b) flagella are presumably
outside the double membrane, indicates that came after capture? Maybe flagella
penetrate double membrane...perhaps were initialy inside or partially inside
and outside.
2) nucleus division does not need to be recreated, can be basically the
same inherited prokaryote cell division (perhaps with minor adjustments), only
within a cell membrane.
3) conjugation already existed as a form of exchanging DNA before
the first eukaryote, it is possible that a complete bacterium could be taken in
through a pilus. Some eukaryotes like spyrogrya still reproduce sexually
through conjugation.
4) DNA was splitting and merging with conjugation in prokaryotes before
eukaryotes.
5) division of nucleus and cytoplasm is different, just like mitochondria, when
the cytoplasm divides is signalled by molecules (as far as I know), and a
nucleus may divide without the cytoplasm dividing (immediately or perhaps ever)
in some protists. (Clearly many metamonads have multiple nuclei). It's
interesting that some metamonads have muliple nuclei (mastigonts), because when
they reproduce it is all integrated, each nuceli is rebuilt (as far as I know).
Maybe that shows how simple throwing together nuclei and cytoplasm is for DNA
for put together and reproduce.
6) two layer membrane around nucleus, is evidence of a
prokaryote being captured in a vacuole.
7) happened for mitochondria, chloroplasts, (and
later red algae and green algae), that is support for a prokaryote similar to
rikettsia, or cyanobacteria being engulfed and forming nucleus.
8) "all eukaryotic HSP70
homologs share in common with the Gram-negative group of eubacteria a number of
sequence features that are not present in any archaebacterium or Gram-positive
bacterium, indicating their evolution from this group of organisms."
9) Most genes related
to the nucleus are related to archaebacteria, while those relating to the
cytoplasm are related to eubacteria.


Perhaps there was a long period of time where the future eukaryote nucleus was
only an organelle, reproducing initially like mitochondria and chloroplasts do,
by themselves, but initiated by the nuclear duplication and cytoplasmic
division (check). Somehow the binary division process of the cytoplasm DNA and
the binary division process of the nucleus-organelle had to merge into one
process.
Either the spindle chromosome method (mitosis) evolved before or
after the nucleus-organelle has taken over the cytoplasm building function.
As
time continued, the process of spindle separation evolved for the
nucleus-organelle. As time continued, the building of the nucleus-organelle
was taken over by the cytoplasmic DNA, still reproducing by binary fission.
I
could see how budding would be a natural evolution for a cell nucleus that
starts as an organelle, is reproduced by cytoplasm DNA and then the DNA is
tranfered back into the nucleus-organelle. The nucelus-organelle would then
recreate the entire cell inside the nucleus (including the cytoplasm DNA
presumably), and presumably it would burst out and continue to copy that way.
Perhaps budding prokaryotes were budding eukaryotes that still had their
cytoplasm DNA that actually lost their nucleus-organelle. Then budding perhaps
evolved into mitosis. I think that mitosis is more similar to binary division
than budding is.

It seems clear that the nucleus-organelle copied itself. Potentially the same
proteins that initiate DNA duplication and cell division for the cytoplasm DNA
simulteously initiate DNA duplication and cell (nucleus-organelle) division in
the nucleus-organelle. So the nucleus-organelle may have been exactly like a
mitochondrion for many years.

Although there are uncertainties, this first
eukaryote is thought to be a member of the broad group of single celled
eukaryotes called "flagellates". It is theorized that later will evolve the
unicellular "ameobozoid" and "ciliate" groups. (this is a little vague and I
am not sure it really covers algae, and the other alveolates, but it does
reduce the complexity of protists)


  
2,725,000,000 YBN
65) DNA in the nucleus changes from a single circular chromosome to linear
chromosomes.

Possibly the prokaryote ancestor of the first eukaryote had linear chromosomes
since some prokaryotes (although very few) are known to have linear chromosomes
instead of or in addition to a single circular chromosome.

Perhaps a DNA strand entered a
cell by conjugation, the circle of DNA was cut to insert the new DNA (plasmid),
but the new DNA strand was not sewn back into the original strand of DNA
creating two strands of DNA which eventually evolved into the first 2
chromosomes.

Perhaps the first eukaryote nucleus was a virus, many of which have linear
chromosomes.

This includes the evolution of histones, proteins which are packed in between
nucleotides in each chromosome.

Presumably DNA duplication (sythesis) of chromosomes (in the nucleus) is
initially identical to DNA duplication of DNA strands or circular DNA.

Some prokaryotes do not have just one circle of DNA. Brucella melitensis has
2 circlular chromosomes. Agrobacterium tumefaciens has a circular and a linear
chromosome. Streptomyces griseus can have one linear chromosome. Borrelia
burgdorferi contains a linear chromosome and a number of variable circular and
linear plasmids. Most eukaryote orgenelles have a single circular chromosome
except for the mitochondria of most cnidarians and some other forms which have
linear chromosomes.



  
2,720,000,000 YBN
208) A eukaryote flagellum (cilium, undulipodium) evolves on early single cell
eukaryotes.

The eukaryote cilia (flagella, undulipodia) may evolve from a prokaryote
flagella connected to the nucleus, from the cytoskeleten, or a symbiotic
prokaryote.

Cilia and eukaryote flagella are structurally the same, but have minor
functional differences. Cilia are a special class of eukaryote flagella.
The
eukarote flagellum is different from prokayote flagellum. The prokaryote
flagallum is a solid structures, made of the protein flagellin, which protrudes
through the plasma membrane.

The eukaryote flagellum (and cilium) contains a "9 plus 2 array", 9
microtubules in a circle with 2 microtubules in the center. Some people think
that the eukaryote flagella and cilia should be called "undulipodia".

In some species the spindles used in mitosis connect to the bases of the
eukaryote cilia (undulipodia), which leads some people to think that the
spindles of mitosis may have evolved from the eukaryote cilia.

Some people think that the eukaryote cilium (flagellum, undulipodia) was a
spirochete (prokaryote) that formed a symbiotic relationship with a eukaryote
host, whose DNA was transfered to the host nucleus. Other possibilities are
that the eukaryote flagellum evolved from prokaryote flagellum, or simply
evolved over time through natural selection.

The eukaryote flagellum protein "tubulin" is thought to be related to a
bacterial replication/cytoskeletal protein "FtsZ" found in some archaebacteria
(archaea).

What method of reproduction this first nucleated cell used is a great mystery.
Among the choices are binary division, budding, or mitosis. My own feeling is
that budding or dual binary division (both nucleus and cytoplasm) was how this
cell initially copied.

The eukaryote flagellum (cilium, undulipodium) is the same
inherited and found on sperm cells.



  
2,720,000,000 YBN
291) For the first time, a cell is not constantly synthesizing DNA and then
having a division period (as is the case for all known prokaryotes), but this
cell has a period in between cell division and DNA synthesis where DNA
synthesis is not performed. Later some cells develop a stage after synthesis
and before cell division.

For the first time, a cell is not constantly synthesizing DNA
(S) and then having a division period (D) (as is the case for all known
prokaryotes), but this cell has a period in between cell division and DNA
synthesis where DNA synthesis is not performed (G1) . Later some cells develop
a stage after synthesis and before cell division (G2).



  
2,719,000,000 YBN
302) If the first eukaryote nucleus was a prokaryote, synchronized duplication
and division of organelle-nucleus and cytoplasm of early eukaryote cell
evolves. Before this, eukaryote cell division usually results in one cell with
no organelle-nuclei and a second cell with 2 organelle-nuclei. Perhaps the
organelle-nuclei attach to the outer cell membrane in the same way the
cytoplasmic DNA do, which allows new cytoplasm growth to separate the two
organelle-nucleus in addition to the cytoplasmic DNA.

Or perhaps the first system
of organized nuclei separation originated with the organelle-nucleus flagella
microtubules grewing into the cytoskeleton, and organized system spindles and
mitosis.

If the nuclear membrane was formed around the DNA within a prokaryote, then
binary division had to adapt to separate the duplicated DNA within the
proto-nucleus (not within the entire cell) which may have been very simple to
evolve. If the cytoplasm grew outside the cell wall of a prokaryote, binary
division would have to adapt to separate that external cytoplasm.



  
2,715,000,000 YBN
72) Mitosis, asexual copying of a haploid (single set of chomosomes) eukaryote
nucleus, evolves in eukaryotes. Before mitosis, there is a synthesis stage
where DNA in the form of chromosomes are duplicated in the nucleus before the
nucleus and cell divide.

explain basic process of mitosis:
prophase, metaphase, anaphase,
telophase

Presumably no prokaryotes have ever reproduced through mitosis. Only
eukaryotes reproduce asexually using mitosis.

Most people accept that some protists were sexual and later lost that ability.
But the majority view now is that the first eukaryotes were asexual, and that
some protists still living now have never had sexual ability.

Because mitosis is complex and similar in detail in all species that do
mitosis, people think that mitosis only evolved once, and was inherited by all
species that do mitosis.

The major differences between this new method of copying, mitosis and the older
method, binary fission (add budding?) are:
1) In mitosis, microtubule spindles
attach to the kinetochore (the protein structure in eukaryotes which assembles
on the centromere and links the chromosome to microtubule polymers from the
mitotic spindle during mitosis) and pull apart the two DNA copies, where in
binary fission the DNA (single chromosome) attaches to a part of the cytoplasm
which pulls apart the two cells.
2) Chromosomes (linear pieces of DNA), not a circle
of DNA is being copied.

People speculate that early mitosis had spindles outside the nucleus, with
chromosomes fastened to the nuclear membrane, as can still be seen in
parabasalia and dinoflagellates, which appear to have primitive nuclei.

In more ancient species the nuclear membrane persists through mitosis (closed
mitosis), but in more recent species, like metazoa, land plants, and many kinds
of protists, the nuclear membrane disintegrates before mitosis and is rebuilt
after (open mitosis).

Most people think that extranuclear spindles (spindles that originate outside
of the nucleus) and closed mitosis evolved first. Only later did pleuromitosis
(spindles rotate 90 degrees, nucleus can be semi-open, or closed) and then
orthomitosis (spindles are on both sides of nucleus and separate chromosomes in
a straight line, nucleus can be open, semi-open or closed) evolve in later
eukaryotes.

It is interesting to think about how how binary fission (or potentially
budding) of prokaryote cells with no nucleus evolved into mitosis and the use
of spindles.

Mitosis, budding, and binary fission are the only asexual methods of
reproduction known.

Perhaps mitosis evolved first only copying the nucleus then later evolved to
make not only a new nucleus but also a new cell around that nucleus.


  
2,711,000,000 YBN
303) Cytoplasmic cell fusion and division evolves. Two eukaryote cells can
merge into one cell with 2 nuclei and then divide back into single 1 nucleus
cells.

Possibly two cells that fuse cytoplasms but not nuclei, may still retain the
system of cytoplasmic DNA and organelle-nucleus attachment to cell membrane
(wall?), but on each half of the new cell, therefore making dual haploid
mitosis (potentially of both cytoplasmic DNA and organelle-nucleus in
synchronized duplication) a simple evolutionary next step.




  
2,710,000,000 YBN
73) Sex (cell and genetic fusion, syngamy, gametogamy) evolves in protists.
Haploid (1 set of chromosomes) eukaryote cells merge and then their nuclei
merge (karyogamy) to form the first diploid (2 sets of chromosomes) cells (the
first zygote).

This fusion of 2 haploid cells results in the first diploid single-celled
organism, which then immediately divides (both nucleus and cytoplasm by
single-division meiosis) back to two haploid cells.

Possibly first, only cytoplasmic merging happened with nuclear merging
(karyogamy) and nuclear division (karyokinesis) evolving later.
Now, two cells with
different DNA can mix providing more chance of variety/mutation. Two
chromosome sets provides a backup copy of important genes (sequences that code
for proteins, or nucleic acids) that might be lost with only a set of single
chromosomes.

The life cycle of future organisms will now have two phases, a gamophase (from
n to 2n (until syngamy)), and zygophase (from 2n to n (until meiosis)). Gamoid
cells are not haploid in polyploid organisms.

Potentially sexual cell and genetic fusion
is what made the first eukaryote cell, and sex in protists may be directly
descended from conjugation in prokaryotes, in other words not evolved from a
different method independently of conjugation, because some metamonads, for
example Saccinobaculus reproduce sexually, and look very much like a prokaryote
sperm cell which formed the nucleus captured in an ovum cell.

For sexual species there are 3 basic life cycles:
1) Haploid (Haplontic) life cycle:
zygotic meiosis. Life as haploid cells, cell division immediately after
creation of zygote from fusion. (All fungi, Some green algae, Many protozoa)
2) Diploid
(Diplontic) life cycle: gametic meiosis. Instead of immediate cell division,
zygote reproduces by mitosis. Haploid gametes never copy by mitosis. (animals,
some brown algae)
3) Haplodiploid (Haplodiplontic, Diplohaplontic, Diplobiontic) life
cycle: sporic meiosis. Diploid cell (sporocyte) meiosis results in 2 haploid
sporophytes (gamonts), not 2 haploid gametes. These haploid cells then
differentiate? or mitosis? to form haploid gametes. Haplodiplontic organisms
have alternation of generations, one generation involves diploid
spore-producing single or multicellular sporophytes (makes spores) and the
other generation involves haploid single or multicellular gamete-producing
multicellular gametophytes (makes gametes). Pants and many algae have this
haplodiplontic life cycle.

These first sexual cells are haplontic, with zygotic meiosis; they reproduce
asexually through mitosis as haploid cells, fusing to a diploid cell without
mitosis, then dividing back into haploid cells.

An important evolutionary step evolves here in that now two cells can
completely merge into one cell. This merge not only includes their nuclei, but
also their cytoplasm (althought the DNA do not merge). Before now, as far as
has ever been observed, no two cells have ever completely merged, although,
through conjugation some prokaryotes have been observed to exchange DNA.

This marks the beginning of the "haplonic lifestyle" with "zygotic meosis",
where the organism is haploid until cell fusion which is immediately followed
by (one-step) meiosis of the zygote, after which the haploid cells continues to
reproduce through mitosis.

Possibly the first sexual organism merged through a form of "autogamy" (both
haploid gametes originate from the same individual, the opposite of "allogamy"
where the gametes originate from different individuals). Some species
reproduce by a form of autogamy (intracellular autogamy), where nuclei (also
called pronuclei) divide and then merge within the same cell before the entire
cell divides. Some metamonads (earliest still living eukaryotes), like
Oxymonas and Saccinobaculus can reproduce asexually by mitosis, but also can
reproduce sexually using this form of autogamy. This may be evidence that some
prokaryote could also merge two entire cells (if the eukaryote nucleus was a
prokaryote). Perhaps prokaryotes evolved full cellular fusion before the first
eukaryote. If that is true, then this initial form of nuclei dividing and
merging (intracellular autogamy) may have existed for some time before full
eukaryote cell merging and synchronized eukayote nucleus and cytoplasm division
evolved. It is difficult to see what selective advantage autogamy could
possibly have since no new DNA is ever introduced into the next generation of
organism, as opposed to "allogamy", where DNA from different individuals is
merged, and which has a clear selective advantage. So perhaps autogamy evolved
after allogamy, although to me it appears that allogamy is more complex than
autogamy, and autogamy would be a perfect starting step to develop the needed
proteins and processes for the more complicated allogamy (autogamy only
involves the duplication and merging of two nuclei, where allogamy involves the
merging of the cell walls, and cytoplasm in addition to the two nuclei.)

This is the beginning of the label "gamete" for haploid cells that can merge to
form a diploid zygote. In addition, the label "gametocyte" or "gamont" is any
polyploid cell that divides (meiosis) into haploid gamete cells which can merge
to form a zygote.

Perhaps there is a relationship between prokaryote spore formation
and the phenomenon of diploid zygotes forming a thick cell wall.

Perhaps the first sex (full cell nucleus and cytoplasm fusion) was
interchangeably isogamous (both gametes are identical and interchangable), with
only one gender, in other words, the first sex on earth was homosexual. Then
later heterogamous gametes evolved, where there were two distinct haploid
gamete cells, usually a large female cell and a smaller flagellated male cell.

Sex also allows organisms to choose reproductive partners that are more likely
to make new organisms that are more likely to survive.

An alternative theory is that a failed mitosis could result in a diploid
nucleus.

What advantage might autogamy of intercellular nuclei have, the added chance of
mistakes in the merging of two nuclei? In addition, why would such a system
(intracellular autogamy) persist if there was no selective advantage? Why
wouldn't oxymonas or saccinobacculus reduce totally to asexual mitosis and or
allogamous sexual reproduction and either never make use of or lose
intracellular autogamous sexual reproduction completely?

This is the first eukaryote cell to have a life cycle that involves two
different kinds of cells.


  
2,710,000,000 YBN
206) Meiosis (one-step meiosis, one DNA duplication and a cell division of a
diploid cell into 2 haploid cells) evolves.

detail one-step meiosis:

The is no DNA crossover or chiasma formation in one-division meiosis,
apparently because either duplication of chromosomes or separation of
chromatids does not occurred.

As far as I know, mitosis and one-step meiosis are the same with the only
exceptions that 1) in meiosis two haploid cells join before cell division, and
2) in mitosis the DNA is duplicated before cell division, but in meiosis the
DNA is not duplicated before cell division.

Meiosis can be one step (one DNA duplication and then one cell division) or two
step (two DNA duplications and then two divisions). Probably one step meosis
evolved first and two step meiosis later.

Meiosis can only function on cells with two or more sets of chromosomes.

The Protists
Pyrsonympha and Dinenympha has up to a four step meiosis.

Because meiosis is similar and complex in detail in all species that do
meiosis, people think that meiosis only evolved once, and was inherited by all
species that do meiosis.


  
2,706,000,000 YBN
299) Duplication of diploid DNA (after 2 haploid cells fuse) evolves.
This is required
for diploid mitosis.

Duplication of diploid DNA may be very similar to duplication of haploid DNA.

Initially perhaps the diploid DNA duplicated, but still divided in one-division
meiosis.




  
2,705,000,000 YBN
210) Mitosis of diploid cells evolves. This begins the "diplontic" life cycle
(with gametic meiosis), where diploid cells (a zygote) can copy asexually
through mitosis after merging. This organism, when haploid, cannot do mitosis
(presumably haploid gamete mitosis will evolve much later in brown algae), and
this is still true in all descendents (including humans) of this single celled
organism.

The proteins and mechanism of mitosis of diploid cells is probably very
similar to mitosis of haploid cells. The most primitive organisms still alive
that are diplontic are the metamonads (e.g. Oxymonads: Notila, Hypermastigotes:
Urinympha, Macrospironympha, Rhynchonympha).




  
2,704,000,000 YBN
296) The origin of gender evolves: sex (cell and nucleus fusion) between two
isogamous (same size) gametes but which have 2 different (+ and -) forms
(genders).

Perhaps the invention of two different genders originated when a flagellated
cell (or nucleus) divided by binary division and only one half of the two new
cells retained the flagellum. Then to differentiate the two cells even more,
but still keep the same DNA template, different proteins could be weighted on
one half of the cell during division to activate various operons in one gender
but not the other once the two DNA pairs are separated.

Perhaps sex where the gametes are the same size but cannot merge themselves
should be called "specific" or "gendered" isogamy, and where any two same sized
gametes can merge called "nonspecific" or "nongendered" isogamy.



  
2,703,000,000 YBN
297) Sex (cell and nucleus fusion) between two different size gamete cells
(heterogamy or anisogamy) evolves in protists.

Some species are heterogamous but two of
the same sized (gender) gametes can fuse to form a zygote.



  
2,702,000,000 YBN
298) Sex (cell and nucleus fusion) between one flagellated gamete and an
unflagellated gamete (oogamy, a form of heterogamy) evolves in protists.

This system is
the system humans inherited.


  
2,700,000,000 YBN
62) Oldest steranes (formed from sterols, molecules made by mitochondria in
eukaryotes) found in northwestern Australia.




  
2,700,000,000 YBN
192) Fossils from the Bulawaya stromatolite, Zimbabwe.


  
2,700,000,000 YBN
214) Biomarkers characteristic of cyanobacteria, 2alpha -methylhopanes,
indicate that oxygenic photosynthesis evolved well before the atmosphere became
oxidizing.



  
2,692,000,000 YBN
300) Diploid cell fusion (Gamontogamy) evolves.
Only a few species exhibit this
property (e.g. the Oxymonad Notilla, Diatoms, Dasicladales {Acetabularia}, in
many foraminiferans, and in gregarines).

Gamontogamy may have evolved into two-step meiosis.

The vast majority of eukaryotes living now that reproduce sexually fuse haploid
cells. All "gametes" are haploid cells that can merge, diploid cells that can
merge are gamonts. Gamonts (Meiocytes) are cells that produce gametes.

In theory this should be very similar if not exactly like haploid cell fusion,
so perhaps this is not a major evolutionary step.



  
2,690,000,000 YBN
295) Meiosis (two step meiosis, two cell divisions with no stage in between
which result in one diplid cell dividing into four haploid cells) evolves.

Meiosis and
mitosis are similar in being process of nucleus and cell division, but are
different.
Differences between meiosis and mitosis:
1) At least one crossover per
homologous pair happens in 2 step meiosis but crossover usually does not happen
in mitosis.
2) Two step meiosis involves cell divisions that happen one after the other,
where mitosis only happens after one DNA duplication (there are never 2 mitoses
together without a DNA duplication between them to my knowledge).

The cell division in two step meiosis that involves a separation of sister
chromatids (not homologous chromosome pairs) is basically identical to mitosis.
For two step meiosis, this is the second nucleus and cell division.

Later multistep
meiosis evolves, where there may be as many as 4 divisions (for example in the
protists Pyrsonympha and Dinenympha).


  
2,650,000,000 YBN
170) First bacteria live on land.



  
2,558,000,000 YBN
171) Phylum Deinococcus-Thermus (Thermus Aquaticus {used in PCR}, Deinococcus
radiodurans {can survive long exposure to radiation}) evolve now.

PHYLUM
Deinococcus-Thermus
CLASS Deinococci
ORDER Deinococcales
ORDER Thermales

The Deinococcus-Thermus are a small group of bacteria comprised of cocci highly
resistant to environmental hazards. There are two main groups. The
Deinococcales include a single genus, Deinococcus, with several species that
are resistant to radiation; they have become famous for their ability to eat
nuclear waste and other toxic materials, survive in the vacuum of space and
survive extremes of heat and cold. The Thermales include several genera
resistant to heat. Thermus aquaticus was important in the development of the
polymerase chain reaction where repeated cycles of heating DNA to near boiling
make it advantageous to use a thermo-stable DNA polymerase enzyme. These
bacteria have thick cell walls that give them gram-positive stains, but they
include a second membrane and so are closer in structure to those of
gram-negative bacteria.



  
2,558,000,000 YBN
172) Genetic comparison shows Eubacteria phylum, Cyanobacteria (ancestor of all
eukaryote chloroplasts {plastids}) evolving now. There is a conflict between
the interpretation of the geological and the genetic evidence as to if oxygen
photosynthesis and cyanobacteria evolved earlier around 3800mybn or here at
2500mybn.

Cyanobacteria get their energy from photosythesis.

Cyanobacteria include unicellular, colonial, and filamentous forms. Some
filamentous cyanophytes form differentiated cells, called heterocysts, that are
specialized for nitrogen fixation, and resting or spore cells called akinetes.
Each individual cell typically has a thick, gelatinous cell wall, which stains
gram-negative. The cyanophytes lack flagella, but may move about by gliding
along surfaces. Most are found in fresh water, while others are marine, occur
in damp soil, or even temporarily moistened rocks in deserts. A few are
endosymbionts in lichens, plants, various protists, or sponges and provide
energy for the host.

Chloroplasts found in eukaryotes (algae and higher plants) most likely
represent reduced endosymbiotic cyanobacteria. This endosymbiotic theory is
supported by various structural and genetic similarities. Primary chloroplasts
are found among the green plants, where they contain chlorophyll b, and among
the red algae and glaucophytes, where they contain phycobilins. It now appears
that these chloroplasts probably had a single origin. Other algae likely took
their chloroplasts from these forms by secondary endosymbiosis or ingestion.

tenative:
CLASS Chroobacteria
CLASS Hormogoneae
CLASS Gloeobacteria

Some live in the fur of sloths, providing a form
of camouflage.


  
2,558,000,000 YBN
315) Phylum Chloroflexi, (Green Non-Sulphur) evolve now.
PHYLUM Chloroflexi
CLASS
Chloroflexi
CLASS Thermomicrobia

The Chloroflexi are a group of bacteria that produce ATP through
photosynthesis. They make up the bulk of the green non-sulfur bacteria, though
some are classified separately in the Phylum Thermomicrobia. They are named for
their green pigment, usually found in photosynthetic bodies called
chlorosomes.

Chloroflexi are typically filamentous, and can move about through bacterial
gliding. They are facultatively aerobic, but do not produce oxygen during
photosynthesis, and have a different method of carbon fixation than other
photosynthetic bacteria. Phylogenetic trees indicate that they had a separate
origin.



  
2,500,000,000 YBN
52) End Archean Era, Start Proterozoic Era.



  
2,500,000,000 YBN
56) Banded Iron Formations start to appear in many places.



  
2,400,000,000 YBN
59) Very large ice age that lasts 200 million years starts now.



  
2,335,000,000 YBN
290) The nucleolus, a sphere in the nucleus that makes ribosomes, evolves.
In some
eukaryotes (thought to be more ancient), the nucleolus just divides during
mitosis, but in other eukaryotes the mitosis is dissolved and rebuilt after
nuclear division.

In euglenids, kinetoplastids, dinoflagellates, some amoebae and some
coccidians, the nucleolus remains visible throughout mitosis and divides into
two, but in the majority of groups the nucleolus dissapears and reforms at
telophase. That the nucleolus can divide by itself suggests that it was once a
free living cell.



  
2,330,000,000 YBN
198) Rough and smooth endoplasmic reticulum evolves in eukaryote cell.
Rough and
smooth endoplasmic reticulum evolves in eukaryote cell.

The rough ER manufactures and transports proteins destined for membranes and
secretion. It synthesizes membrane, organellar, and excreted proteins. Minutes
after proteins are synthesized most of them leave to the Golgi apparatus within
vesicles. The rough ER also modifies, folds, and controls the quality of
proteins.

The smooth ER has functions in several metabolic processes. It takes part in
the synthesis of various lipids (e.g., for building membranes such as
phospholipids), fatty acids and steroids (e.g., hormones), and also plays an
important role in carbohydrate metabolism, detoxification of the cell (enzymes
in the smooth ER detoxify chemicals), and calcium storage. It also is a large
transporter of nutrient found in each cell.




  
2,325,000,000 YBN
199) Golgi Body (Golgi Apparatus, dictyosome) evolves in eukaryote cell.
The primary
function of the Golgi apparatus is to process proteins targeted to the plasma
membrane, lysosomes or endosomes, and those that will be formed from the cell,
and sort them within vesicles. It functions as a central delivery system for
the cell.

Most of the transport vesicles that leave the endoplasmic reticulum (ER),
specifically rough ER, are transported to the Golgi apparatus, where they are
modified, sorted, and shipped towards their final destination. The Golgi
apparatus is present in most eukaryotic cells, but tends to be more prominent
where there are many substances, such as proteins, being secreted. For example,
plasma B cells, the antibody-secreting cells of the immune system, have
prominent Golgi complexes.




  
2,310,000,000 YBN
200) The golgi body in eukaryote cells makes lysosomes which fuse with
endosomes. The various molecules in lysosomes digest the contents of the
endosome, which then exits the cell as waste.





  
2,305,000,000 YBN
63) A parasitic bacterium, a bacterium that can only live in other bacteria,
closely related to Rickettsia prowazekii, an aerobic alpha-proteobacteria that
causes louse-borne typhus, enters an early eukaryote cell. As time continues a
symbiotic relationship evolves, where the Rickettsia forms the mitochondria,
organelles of every euokaryote cell. The mitochondria perform the Acid Citric
Cycle (Krebs Cycle), using oxygen to breakdown glucose into CO2 and H2O, and
provide up 38 ATP molecules. Mitochondria reproduce by themselves, and are not
created by the DNA in the cell nucleus. As time continues some of the DNA from
the mitochondria merges with the cell nucleus DNA. Mitochondria produce sterol
used to make the eukaryote cell wall flexible. Because mitochondria need
Oxygen, but the level of oxygen is very low on earth, oxygen may be provided by
photosynthesizing cyanobacteria living near these cells.

All eukaryotes alive today either have mitochondria except the amitochondriate
excavates (metamonads), the most ancient of the eukaryotes alive today. That
parabasalids have hydrogenosomes, anaerobic organelles that seem to have
evolved from mitochondria, many people think amitochondriate species lost their
mitochondria over time.

This changes the eukaryote cell from an anaerobic to aerobic
unicellular organism.
This early mitochondria may have "tubular christae".
Perhaps there was a
period of time where a system evolved to make sure both halves received
mitochondria during cell division.

Protists with discoidal mitochondrial cristea will later evolve from the Bikont
tubular mitochondrial christae branch.

For the most part:
1) Excavates, Amoebozoa, and Chromealveolates have or had tubular
christae,
2) Discicristata (Euglenozoa) have discoidal christae.
3) Cryptomonads,
Glaucophytes, Red Algae, Green Algae, Plants, Fungi, Animals all have flat
christae.

From this point on, all eukaryotes will need Oxygen to use mitochondria and
receive the ATP made by mitochondria.

One theory is that, as more O2 is
produced at the surface of the ocean, protists (which require oxygen for
mitochondria) can move to the ocean floor.



  
2,303,000,000 YBN
203) Bikonts (two cilia) evolve from Unikonts (one cilium). Bikonts (also
called anterokonts for having anterior {forward facing} cilia) will evolve into
the vast majority of the Protist and all of the Plant Kingdoms. The Unikonts
will evolve into the ameobozoa (tenatively), and the opisthokonts (ancestrally
posterior cilium) which include the entire Fungi and Animal Kingdoms.


Since members of both the unikont (animals, fungi) and bikont (metamonads,
plants) can reproduce sexually, sex had to evolve before this branching,
presuming sexual reproduction is strictly inherited and did not evolve twice.


  
2,300,000,000 YBN
47) Most recent evidence of uraninite, a mineral that cannot exist for much
time if exposed to oxygen, indicating that free oxygen is accumulating in the
air of earth for the first time.




  
2,300,000,000 YBN
48) Oldest Red Beds, iron oxide formed on land, begin here and are evidence of
more free oxygen in the air of earth.




  
2,300,000,000 YBN
219) Genetic comparison shows the oldest line of eukaryotes still in existence,
the oldest living protists, in the Phylum "Metamonada" (Excavates) originating
now. This is where the eukaryote line is created and separates from the
archaebacteria (archaea) line. Most of these species have an excavated ventral
feeding groove, and all lack mitochondria. Mitochondria are thought to have
been lost secondarily, although this is not certain.

PHYLUM Metamonada
ORDER Carpediemondida
ORDER
Diplomonadida
ORDER Retortamonadida
CLASS Parabasalia
ORDER Trichomonadida
ORDER Hypermastigida
CLASS Anaeromonada
ORDER Oxymonadida
ORDER
Trimastigida
Includes Diplomonad "Giardia", and Parabasalid "Trichomonas vaginalis".
The trophozoite
form of Giardia does age and die.
Most Metamonads reproduce asexually through closed
(the nuclear membrane does not dissolve during mitosis) mitosis (and involves
an external spindle? is pluromitosis?), but some species are "faculatively
sexual" (can reproduce sexually in addition to asexually). So already by the
time of these most ancient of the now living eukaryotes, sex had evolved.
eat
bacteria?

Some people have this phylum as part of the group "Excavates" which includes
the Phyla (Metamonada, Percolozoa, and Euglenozoa).

The classification of the protists is far from complete and settled. There are
currently more than one existing classification scheme for the protists.

features of parabasalia and metamonada:
gamete type: flagellated
haplontic and
diplontic
condensed chromosomes in some species
mitotic spindle:
parabasalia:
external
metamonadea: internal
polar structures:
parabasalia: flagellar root
me
tamonadea: kinetosome
flagella:
parabasalia: 4 to many
metamonadea: 2,4
heteroko
nt, isokont, anisokont: anisokont (Anisokont flagella are those flagella that
are unequal in length, form, or direction. ) (Isokont flagella are those
flagella that are equal in length, form, and direction.)
(The name heterokont
refers to the characteristic form of these cells, which typically have two
unequal flagella. The anterior or tinsel flagellum is covered with lateral
bristles or mastigonemes, while the other flagellum is whiplash, smooth and
usually shorter, or sometimes reduced to a basal body. The flagella are
inserted subapically or laterally, and are usually supported by four
microtubule roots in a distinctive pattern. )
flagellate stages: trophic
life
forms:
unicellular: flagellated
multicellular: none
cell covering: naked


  
2,156,000,000 YBN
150) Amino acid sequence comparison shows the eubacteria and archaebacteria
line separating here at 2,156 mybn, first archaebacteria.


  
2,000,000,000 YBN
293) Genetic comparison shows the the Eukaryote Phylum "Loukozoa" (Jakobea and
Malawimonadea) originating now. These species have mitochondria with tubular
cristae, and are the most ancient species that still have mitochondria.

This species is the most ancient known species to have a shell. This first
hard shells (lorika) made of calcium carbonate (Calcite CaCO3), plates of
silica (SiO2), or carbon-based molecules evolve around the single-celled
species living in the ocean.

Perhaps this shell served to protect the cell from external damage from being
eaten by other eukaryotes (zooplankton), infection by bacteria or viruses,
control of buoyancy, to filter UV light, against damage by non-living sources.


Jakobids and Malawimonads are also grouped as Excavates because they have a
ventral feeding groove.

Jakobids are flagellates with two flagella located at the anterior end of a
ventral feeding groove (i.e., are excavate), with mitochondria, freely swimming
or loricate (with protective shell).

Flagellar apparatus with two basal bodies giving rise to two major microtubular
roots, which support the margins of the ventral groove. Other cytoskeletal
microtubules arise directly or indirectly from the basal bodies, no
extrusomes.

Jakobids have tubular mitochondrial cristae (transforming to flat cristae in
Jakoba libera). (1) This indicates that flat evolved from tubular cristae.

PHYLUM Loukozoa
ORDER Jakobida
ORDER Malawimonadida

Reproduction=mitosis?

ORDER Jakobida
FAMILY Histionidae
The jakobid family "Histionidae" reproduce asexually by
binary fission. In this family no sexual reproduction has been observed yet.
(1)
FAMILY Jakobidae


  
1,990,000,000 YBN
202) Eukaryotes with discoidal cristae mitochondria split from the tubular
christae line.

This is the origin of the Discicristata: species that have discoid
mitochondrial cristae and, in some cases, a deep (excavated) ventral feeding
groove.

The Discicristata are Acrasid slime molds, vahlkampfiid amoebas, euglenoids,
trypanosomes, and leishmanias.



  
1,990,000,000 YBN
301) Haplodiplontic (Diplohaplontic, Diplobiontic) life cycle (organism with
both diploid and haploid "alternate life stages" that reproduce asexually by
mitosis) with "sporic meiosis" evolves.

In this life cycle haploid gametes fuse to form a diploid zygote which divides
by meiosis producing haploid spores that produce (differentiate?) gametes,
starting the cycle again.

Initially these species are single celled in both stages (like Haptophyta).

All plants,
most brown algae, blastocladiid chytrids, many red algae, and some filamentous
green algae (e.g. Cladophora) and foraminifera have haplodiploid life cycles.

Initially, these organisms are single celled, but later the mitosis stages will
become multicellular when the cells that result from mitosis stick together.
The only? example of this is Haptophyta, where diploid cells divide in sporic
meiosis, into haploid cells (gamonts) which then divide into gametes.

Of the
diplohaplonic species, those where the haploid and diploid stages look the same
are called "isomorphic" and those where the two stages look different are
called "heteromorphic".

In land plants the haploid (gametophyte) stage is reduced to only a few cells.
Since double DNA chromosomes (diploid) provides more possibilities than a
single chromosome, diploid organisms have a selective advantage over haploid
organisms.



  
1,988,000,000 YBN
317) Eukaryotes that have mitochondria with flat christae evolve from those
with tubular christae.




  
1,982,000,000 YBN
87) Genetic comparison shows the most primitive living members of the Phylum
"Euglenozoa" (euglenids, leishmania, trypanosomes, kinetoplastids) evolved at
this time.

This is the oldest eukaryote to exhibit colonialism. Perhaps eukaryote
colonialism is partially or fully inherited from prokaryotes, but colonialism
may have evolved independently again in eukaryotes.

This is the most ancient species known to have a cell covering, which is of the
type "pellicle".

No examples of sexual reproduction in the group have been found.
Reproduction is through closed mitosis and involves an internal spindle. At
least one account of a sexual cycle has been reported in Scytomonas.

The chloroplasts are contained in three membranes and are pigmented similarly
to the plants, suggesting they were retained from some captured green alga.
All
Euglenozoa have mitochondria with discoid cristae, which in the kinetoplastids
characteristically have a DNA-containing granule or kinetoplast associated with
the flagellar bases.
I think they are still haploid, mitosis duplicates in nucleus?
Euglenozoa
age?

This group is sometimes called "Discicristates" because all members have
mitochondria with "discoidal cristae".

Euglenids are the first eukaryotes with an eyespot. Most colored euglenids
also have a stigma or eyespot, which is a small splotch of red pigment on one
side of the flagellar pocket. This shades a collection of light sensitive
crystals near the base of the leading flagellum, so the two together act as a
sort of directional eye. Euglenozoa eyepots evolved from chloroplasts. This
is the beginning of a light sensory system which evolves to eyes?

A small number of euglinids have chloroplasts and can photosynthesize. In
these species, the chloroplasts contain three membranes and are thought to have
evolved at least 900 million years later from a captured green alga.

Euglenoids, however, share reproductive habits with their kinetoplastid
relations by reproducing mainly by asexual binary fission. Euglenoids reproduce
very rapidly, absorbing their flagellum and dividing haploid cells through
mitosis. Mitosis produces 4-8 flagellated haploid cells, called zoospores. The
zoospores then break out of the parent cell and grow to full size.

condensed chromosomes: yes in all kinetoplasts, and some euglenophyta.
polar
structures: none
number of flagella: kinetoplastids=(1 in some) 2,
euglenophyta=2 (4 in some)
life forms:
unicellular: flagellated
multicellular:
colonial
cell covering: pellicle

2. Euglenoids are small (10-500 µm) freshwater unicellular organisms.
3.
One-third of all genera have chloroplasts; those that lack chloroplasts ingest
or absorb their food.
4. Their chloroplasts are surrounded by three rather
than two membranes.
a. Their chloroplasts resemble those of green algae.

b. They are probably derived from a green algae through endosymbiosis.
5. The pyrenoid
outside the chloroplast produces an unusual type of carbohydrate polymer
(paramylon)
not seen in green algae.
6. They possess two flagella, one of
which typically is much longer and than the other and projects
out of a
vase-shaped invagination; it is called a tinsel flagellum because it has hairs
on it.
7. Near the base of the longer flagellum is a red eyespot that
shades a photoreceptor for detecting light.
8. They lack cell walls, but
instead are bounded by a flexible pellicle composed of protein strips
side-by-side.
9. A contractile vacuole, similar to certain protozoa, eliminates
excess water.
10. Euglenoids reproduce by longitudinal cell division; sexual
reproduction is not known to occur.

PHYLUM Euglenozoa
CLASS Euglenoidea
CLASS Diplonemea
CLASS Kinetoplastea
CLASS Postgaardea

Those Euglnozoa that do not
photosynthesize feed on bacteria (phagocytosis) or feed through absorption
(osmosis) of nutrients.
Most are small, around 15-40 µm in size, although many euglenids
get up to 500 µm long.

Most Euglenozoa have two flagella, usually one leading and one trailing.

Some euglenozoa cause parasitic disease in other species.
A kinetoplastid member of
Euglenozoa, such as trypanosoma brucei which causes African sleeping sickness,
is transmitted from host to host by a vector, most commonly the tsetse fly.
In most
forms there is an associated cytostome (mouth) supported by one of three
microtubule groups that arise from the flagellar bases.

Average life cycle=? days
Average age of euglenozoa life=? days

Trypanosomes (Kinetoplastids) typically have complex life-cycles involving more
than one host, and go through various morphological stages.

1000 Species of Euglenoids (euglenophyta).


  
1,982,000,000 YBN
294) Genetic comparison shows the Phylum "Percolozoa" (also called
"Heterolobosea") (acrasid slime molds) evolved at this time.

Percolozoa are a group
of heterotrophic colourless protozoa, including many that can transform between
amoeboid, flagellate, and encysted stages. These are collectively referred to
as amoeboflagellates, schizopyrenids, or vahlkampfids. They also include the
acrasids, a group of social amoebae that aggregate to form sporangia.

Very closely related to Euglenozoa.
All characteristics are like Euglenozoa:
Percolozoa
have mitochondria with discoid christae.
No examples of sexual reproduction in the group
have been found. Reproduction is through closed mitosis and involves an
internal spindle.
No chloroplasts (check) or (The chloroplasts are contained in
three membranes and are pigmented similarly to the plants, suggesting they were
retained from some captured green alga.)
I think they are still haploid, mitosis
duplicates in nucleus?
Percolozoa age?
Percolozoa are sometimes included in the group
"Discicristates" because all members have mitochondria with "discoidal
cristae".
No eyespots.

closed mitosis with internal spindle.

The Percolozoa are the most ancient species to have members that move by
pseudopodia, like amoeba.

PHYLUM Percolozoa
CLASS Heterolobosea
ORDER Schizopyrenida Singh, 1952
ORDER Acrasida
Shröter, 1886 (acrasids, cellular slime molds)
ORDER Lyromonadida Cavalier-Smith,
1993
CLASS Percolatea

ORDER Acrasida (acrasids, cellular slime molds):
a. Cellular slime molds
(Phylum Acrasiomycota) (ORDER Acrasida) exist as individual amoeboid cells.
(Plasmodial slime molds, mycetozoa, which evolve later, exist as a plasmodium.
)
b. They live in soil and feed on bacteria and yeast.
c. As
food runs out, amoeboid cells release a chemical that causes them to aggregate
into a pseudoplasmodium.
d. The pseudoplasmodium stage is temporary; it gives rise to
sporangia that produce spores.
e. Spores survive until more favorable
environmental conditions return; then they germinate.
f. Spore germinate to
release haploid amoeboid cells, which is again the beginning of asexual cycle.

g. Asexual cycle occurs under very moist conditions.

Percolozoa feed on
bacteria (phagocytosis) or feed through absorption (osmosis) of nutrients.
(check)
Most are small, around 15-40 µm in size, although many euglenids get up to 500
µm long.

The flagellate stage is slightly smaller, with two or four anterior flagella
anterior to the feeding groove.

Average life cycle=? days
Average age of Percolozoa life=? days

Most Percolozoa are found as bacterivores in soil, freshwater, and on feces.
There are a few marine and parasitic forms, including the species Naegleria
fowleri, which can become pathogenic in humans and is often fatal. The group is
closely related to the Euglenozoa, and share with them the unusual though not
unique characteristic of having mitochondria with discoid cristae. The presence
of a ventral feeding groove in the flagellate stage, as well as other features,
suggests that they are part of the excavate group.

The amoeboid stage is roughly cylindrical, typically around 20-40 μm in
length. They are traditionally considered lobose amoebae, but are not related
to the others and unlike them do not form true lobose pseudopods. Instead, they
advance by eruptive waves, where hemispherical bulges appear from the front
margin of the cell, which is clear. The flagellate stage is slightly smaller,
with two or four anterior flagella anterior to the feeding groove.

Usually the amoeboid form is taken when food is plentiful, and the flagellate
form is used for rapid locomotion. However, not all members are able to assume
both forms. The genera Percolomonas, Lyromonas, and Psalteriomonas are known
only as flagellates, while Vahlkampfia, Pseudovahlkampfia, and the acrasids do
not have flagellate stages. As mentioned above, under unfavourable conditions,
the acrasids aggregate to form sporangia. These are superficially similar to
the sporangia of the dictyostelids, but the amoebae only aggregate as
individuals or in small groups and do not die to form the stalk.

The Heterolobosea were first defined by Page and Blanton in 1985 as a class of
amoebae, and so only included those forms with amoeboid stages. Cavalier-Smith
created the phylum Percolozoa for the extended group, together with the
enigmatic flagellate Stephanopogon. (currently I have stephanopogon colpoda
images under ciliates...) He maintained the Heterolobosea as a class for
amoeboid forms, but most others have expanded them to include the flagellates
as well.

Stephanopogon closely resembles certain ciliates and was originally classified
with them, but is now considered a flagellate.


  
1,980,000,000 YBN
38) Multicellularity evolves in a protist.

Multicellularity is a very important event in the evolution of life on earth.
With multicellular organisms, larger sized organisms could evolve.

There are many uncertainties surrounding the origin of multicellularity.
Multicellularity may have evolved independently for Plants, Fungi and Animals,
or multicellularity may have evolved only once in eukaryotes.

The key feature of this cell is that a multicellular organism is made from a
single cell and the multicellular organism is not a collection of independent
cells (colonialism). The main difference between this organism and
single-celled organisms is the way the cells stay fastened together after cell
division.

Which species was the first multicellular species is not clear.
Multicellularity is found in all 3 life cycles (haplontic, diplontic,
haplodiplontic). The 3 main life cycle types (haplontic, etc.) probably
evolved in single cell species before multicellularity evolved. If
multicellularity evolved once and is inherited, perhaps all multicellular
organism descended from a single haplodiplontic organism.

These multicellular organisms have undifferentiated cells in the multicellular
stage (all cells in the haploid or diploid multicellular organism are made of
one kind of cell).

Dinophyta, and Fungi are multicellular Haplontic species.
Most
animals are multicellular Diplontic species.
Most brown algae and all plants are
multicellular Haplodiplontic species.

The vast majority of multicellular organisms reproduce only through sex,
although there are exceptions (like some plants and rotifers) which have lost
the ability to sexually reproduce or can also reproduce asexually. In
multicellularity, one cell goes on to produce all the cells in a multicellular
species, so that each individual organism is genetically unique. This cell is
usually a diploid zygote, but can be a haploid cell.

This protist is most likely sexual, and multicellularity evolved only in a
species that reproduces sexually.

Some describe algae multicellularity as "filamentous".

The first multicellular eukaryuotes are presumably undifferentiated. For
haplontic these cells are all gametes, for diplontic these cells are all
capable of meiosis to form gametes, for haplodiplontic, in the haploid stage
the cells are all gamete producing, in the diploid stage the cells are all
spore producing.

Some people think that multicellular organisms arose at least six times: in
animals, fungi and several groups of algae.

What did the first multicellular
organism look like? Perhaps it was a haplontic protist that only did one or
more haploid mitoses, but this time the cells stuck together (perhaps similar
to the way bacteria form filaments).

An interesting aspect of multicellular organisms is that oxygen must still
reach each cell for mitochondria to work, and so this requires that the cells
be only 1 cell thick, or if thicker have some kind of (circulatory) system for
oxygen to reach each cell.


  
1,978,000,000 YBN
15) Multicellularity with differentiation evolves.

Multicellular organisms are no longer all haploid or diploid gamete producing
cells (or spore producing if haplodiplontic), but are made of gamete (or spore)
producing cells in addition to somatic cells which copy asexually through
mitosis.

Now, in addition to being large multicell organisms, multicellular organisms
can have differentiated cells that form a variety of different shaped
structures, and perform different functions.

This process will evolve to the metazoan
multicellular differentiation that arises from a single zygote cell, where
cells have different functions and shapes.
Differentiation evolves for a second time in
eukaryotes?
this is not the first monoadmulti one cell leading to a multicellular organism
(attached, free, interchangible)?
where a multicellular organism is made from one cell
(interchangable, specific cells: genetic specificity).

It is unknown how multicellular life stages happen. For example, why one
specific cell line of many produced from mitosis of a zygote will go on to do
meiosis producing the haploid gamete cells which will fuse to form the next
zygote, but the many other cells made from, for example, one of the two cells
made after the zygote divides, will not contain the line of cells that
ultimately make the gamete producing cells which continue the life cycle of the
organism. Since presumably each cell in an organism contains an identical
genome, perhaps a gamete producing cell can be made from any cell if specific
proteins are present, or perhaps there is a protein which simply points to a
certain location in the DNA which is located at a different location in the DNA
for every cell, or perhaps some other explanation answers the question of how
cell differentiation can happen when each cell has the same genome.

A (diploid) zygote cell (the cell made by two merging gamete cells) now divides
to form all cells in the differentiated multicellular organism, and is said to
be "totipotent". Totipotent cells differentiate into "pluripotent" cells which
can make most but not all cells in the organism. Pluripotent cells
differentiate into "multipotent" (can make a number of cells) or "unipotent"
cells (can only make one kind of cell).



  
1,974,000,000 YBN
169) For those that think algae are plants, this is where the plant kingdom
begins with the evolution of brown algae (phaeophyta).



  
1,973,000,001 YBN
88) Genetic comparison shows the ancestor of the "Chromalveolates" evolving
now. Chromalveolates include the Chromista and Alveolata. The Chromista
include the 3 Phyla Haptophyta, Cryptophyta (Cryptomonads), and
Heterokontophyta (brown algae {kelp}, diatoms, water molds). Alveolata include
the 3 Phyla Dinoflagellata, Apicomplexa (Malaria, Toxoplasmosis), and
Ciliophora (ciliates).

Chromealveolates have mitochondria with tubular cristae.

Thomas Cavalier-Smith writes: "The chromalveolate clade (Cavalier-Smith 1999)
and its constituent taxa, kingdom Chromista (Cavalier-Smith 1981) and protozoan
infrakingdom Alveolata (Cavalier-Smith 1991b), were all proposed based on
morphological, biochemical, and evolutionary reasoning about protein targeting
before there was sequence evidence for any of them. Now all are strongly
supported by such evidence. Chromalveolates comprise all algae with chlorophyll
c (the chromophyte algae) and all their nonphotosynthetic descendants. They
arose by a single symbiogenetic event in which an early unicellular red alga
was phagocytosed by a biciliate host and enslaved to provide photosynthate
(Cavalier-Smith 1999, 2002c, 2003a). The strongest evidence that this occurred
once only in their cenancestor is the replacement of the red algal plastid
glyceraldehyde phosphate dehydrogenase (GAPDH) by a duplicate of the gene for
the cytosolic version of this enzyme in all four chromalveolate groups with
plastids: the alveolate sporozoa and dinoflagellates and the chromist
cryptomonads and chromobiotes (Fast et al. 2001). It would be incredible for
such gene duplication, retargeting by acquiring bipartite targeting sequences,
and loss of the original red algal gene to have occurred convergently in four
groups, but it was already pretty incredible that these groups would all have
evolved a similar protein-targeting system independently and all happened to
enslave a red alga, evolve chlorophyll c, and place their plastids within the
rough endoplasmic reticulum (ER) independently. Yet many assumed just this
because of the false dogma that symbiogenesis is easy and the failure of all
these groups to cluster in rRNA trees. For chromobiotes this retargeting of
GAPDH has been demonstrated only for heterokonts-information is lacking for
haptophytes. However, there are five strong synapomorphies for Chromobiota,
making it highly probable that the group is holophyletic (Cavalier-Smith 1994).
They share the presence of the periplastid reticulum in the periplastid space
instead of a nucleomorph like cryptomonads, they uniquely make the carotenoid
fucoxanthin and chlorophyll c3, they uniquely have a single autofluorescent
cilium, and they have tubular mitochondrial cristae with an intracristal
filament. Five plastid genes now extremely robustly support the monophyly of
both chromists and chromobiotes (Yoon et al. 2002). We are confident that
comparable sequence evidence from nuclear genes will also eventually catch up
with the general biological evidence for the holophyly of chromobiotes to
convince even the most skeptical, who ignore or discount such valuable evidence
that chromobiotes are holophyletic."

Chromista include phyla:
Heterokontophyta (heterokonts) (many classes) (includes
colored: golden algae, axodines, diatoms, yellow-green algea, brown algae,
colorless: water moulds, slime nets)
Haptophyta
Cryptophyta (cryptomonads) (many genera)

Alveolates include the phyla:
Dinoflagellata (Dinoflagellates)
Apicomplexa (Apicomplexans)
Ciliophora (ciliates)

In 1981 Cavalier-Smith created a new kingdom called "Chromista" in which all
chromalveolates are placed.

There are a number of classification schemes for
the kingdom Protista and no one system has emerged as most popular yet.


  
1,972,000,000 YBN
304) Genetic comparison shows the ancestor of Chromalveolate Phlyum Haptophyta
evolving now.

Some Haptophytes are haplodiploid (alternate between haploid and
diploid cycles that both have mitosis), and this group is the most primitive
with a haplodiploid life cycle.

Haptophytes are single cellular.

Haptophytes are found only in all oceans (marine) and are flagellates, almost
all with plastids with chlorophylls a and c, with two flagella and one
additional locomotor/feeding organelle, the haptonema.

Haptophyta are a group of algae (phytoplankton).
The chloroplasts are pigmented similarly to
those of the heterokonts, such as golden algae, but the structure of the rest
of the cell is different, so it may be that they are a separate line whose
chloroplasts are derived from similar endosymbionts.
The cells typically have two slightly
unequal flagella, both of which are smooth, and a unique organelle called a
haptonema, which is superficially similar to a flagellum but differs in the
arrangement of microtubules and in its use.
Haptophytes have tubular mitochondria
cristae.
Most haptophytes are coccolithophores, which live strictly in the oceans
(marine) and are ornmmented with calcified scales called coccoliths, which are
sometimes found as microfossils. Other planktonic haptophytes of note include
Chrysochromulina and Prymnesium, which periodically form toxic marine algal
blooms. Both molecular and morphological evidence supports their division into
five orders.

Emiliania is a small organism that is famous for turning huge portions of the
ocean bright turquoise during its blooms. They are also known for contributing
to the white cliffs of Dover because of the calcite in their coccolith cell
structure. They play a very important role in the carbon cycle in the ocean
because they form calcium carbonate exoskeletons that sink to the bottom of the
ocean floor when they die. They are also one of the worlds major calcite
producers.

Sexual reproduction: Asexual, Open mitosis with spindle nucleating
(originating?) in cytoplasm.
Phaeocystis colonial cells diploid, motile cells haploid or
diploid; reproduction by vegetative division of non-motile cells and
fragmentation of colonies, vegetative division of motile cells, or by fusion of
gametes.

Members of the Haptophytes Genus "Phaocystis" form colonies (see photo).

Haptophytes are also called "Prymnesiophytes"

Some Haptophyta have hard shell made of calcium carbonate evolves around the
single-celled species living in the ocean.

KINGDOM Protista (Chromalveolata)
PHYLUM Haptophyta
CLASS
Pavlovophyceae
ORDER Pavlovales
CLASS Prymnesiophyceae
ORDER Prymnesiales
ORDER Phaeocystales
ORDER Isochrysidales
ORDER Coccolithales


  
1,971,000,000 YBN
305) Genetic comparison shows the ancestor of the Chromalveolate Phylum
"Cryptophyta" (Cryptomonads) evolving now.

The cryptomonads are a small group of
flagellates, most of which have chloroplasts. They are common in freshwater,
and also occur in marine and brackish habitats. Each cell has an anterior
groove or pocket with typically two slightly unequal flagella at the edge of
the pocket.
Cryptomonads distinguished by the presence of characteristic
extrusomes called ejectisomes, which consist of two connected spiral ribbons
held under tension. If the cells are irritated either by mechanical, chemical
or light stress, they discharge, propelling the cell in a zig-zag course away
from the disturbance. Large ejectisomes, visible under the light microscope,
are associated with the pocket; smaller ones occur elsewhere on the cell.
Crypto
monads have one or two chloroplasts, except for Chilomonas which has
leucoplasts and Goniomonas which lacks plastids entirely. These contain
chlorophylls a and c, together with phycobilins and other pigments, and vary in
color from brown to green. Each is surrounded by four membranes, and there is a
reduced cell nucleus called a nucleomorph between the middle two. This
indicates that the chloroplast was derived from a eukaryotic symbiont, shown by
genetic studies to have been a red alga.

A few cryptomonads, such as Cryptomonas, can form palmelloid stages, but
readily escape the surrounding mucus to become free-living flagellates again.
Cryptomonad flagella are inserted parallel to one another, and are covered by
bipartite hairs called mastigonemes, formed within the endoplasmic reticulum
and transported to the cell surface. Small scales may also be present on the
flagella and cell body. The mitochondria have flat cristae, and mitosis is
open; sexual reproduction has also been reported.

Originally the cryptomonads were considered close relatives of the
dinoflagellates because of their similar pigmentation. Later botanists treated
them as a separate division, Cryptophyta, while zoologists treated them as the
flagellate order Cryptomonadida. There is considerable evidence that
cryptomonad chloroplasts are closely related to those of the heterokonts and
haptophytes, and the three groups are sometimes united as the Chromista.
However, the case that the organisms themselves are related is not very strong,
and they may have acquired chloroplasts independently.

Crytomonads often forms blooms in greater depths of lakes, or during winter
beneath the ice. The cells are usually brownish in color, and have a slit-like
furrow at the anterior. They are not known to produce any toxins and are used
to feed small zooplankton, which is the food source for small fish in fish
farming.

Reproduction:
Number of species:
Size and shape: 10-50 μm in size and flattened in shape
Mitochondria
Christae: flat (which is unusual, as most chromalveolates have tubular
christae). Cryotphyta may be more closely related to the Plant Kingdom and
nearest Glaucophyta which also have flat christae.

After one species of jakobid that changes tubular to flat christae, cryptophyta
are the most ancient phylum to have flat christae.

KINGDOM Protista
(Chromalveolata)
PHYLUM Cryptophyta
CLASS Cryptomonadea
ORDER Pyrenomonadales Novarino & Lucas, 1993
ORDER
Cryptomonadales Pascher, 1913


  
1,970,000,000 YBN
306) Genetic comparison shows the ancestor of the Chromalveolate Phylum
"Heterokontophyta" (Heterokonts also called Stramenopiles) evolving now.
Heterokonts include brown algae, diatoms, golden algae, axodines, yellow-green
algae, water moulds and slime nets.

Heterkonts evolved very near the same time as
the Euglinozoa did.
Heterokonts all have mitochondria with tubular christae. The
motile cells of heterokonts all have two unequal cilia (flagella), one "tinsel"
(covered with hairs {mastigonemes}) cilium and one "whiplash" (free of hair)
cilium.

KINGDOM Protista (Chromalveolata)
PHYLUM Heterokontophyta
Colored groups
CLASS Chrysophyceae (golden algae)
CLASS
Synurophyceae
CLASS Actinochrysophyceae (axodines)
CLASS Pelagophyceae
CLASS Phaeothamniophyceae
CLASS Bacillariophyceae
(diatoms)
CLASS Raphidophyceae
CLASS Eustigmatophyceae
CLASS Xanthophyceae (yellow-green algae)
CLASS
Phaeophyceae (brown algae)
Colorless groups
CLASS Oomycetes(water moulds)
CLASS
Hypochytridiomycetes
CLASS Bicosoecea
CLASS Labyrinthulomycetes(slime nets)
CLASS Opalinea
CLASS
Proteromonadea


  
1,969,000,000 YBN
307) Chromalveolate Heterokont, Brown Algae (Phaeophyta) evolves now.

Brown Algae is the most genetically ancient multicellular organism still living
on earth. In addition to being first to evolve multicellularity, cell
differentiation (cells of different types) is already present in all brown
algae.

Genetic comparison shows the ancestor of the Chromalveolate Heterokont Brown
Algae (Phaeophyta) evolving now.

Brown Algae is the most genetically ancient multicellular organism still living
on earth. In addition to being first to evolve multicellularity, cell
differentiation (cells of different types) is already present in all brown
algae.

Brown algae belong to a large group called the heterokonts, most of which are
colored flagellates. Most contain the pigment fucoxanthin, which is responsible
for the distinctive greenish-brown color that gives brown algae their name.
Brown algae are unique among heterokonts in developing into multicellular forms
with differentiated tissues, but they reproduce by means of flagellate spores,
which closely resemble other heterokont cells. Genetic studies show their
closest relatives are the yellow-green algae.

Most Brown algae are haplodiplontic.

KINGDOM Protista (Chromalveolata)
PHYLUM Heterokontophyta
Colored groups
CLASS Phaeophyceae
(brown algae)

Some people view brown algae as being in the plant kingdom, and others as being
a multicellular protist in the protist kingdom.


2. Brown algae range from small forms with simple filaments to large
multicellular (50-100 m long) seaweeds. (Fig. 30.8)
3. Brown algae have
chlorophylls a and c and a fucoxanthin that give them their color.
4. Their
reserve food is a carbohydrate called laminarin.
5. Seaweed refers to any large,
complex alga.
6. Their cell walls contain a mucilaginous water-retaining
material that inhibits desiccation.
7. Laminaria is an intertidal kelp that is
unique among protists; this genus shows tissue differentiation.
8. Nereocystis and
Macrocystis are giant kelps found in deeper water anchored to the bottom by
their holdfasts.
9. Individuals of the genus Sargassum sometimes break off from
their holdfasts and form floating masses.
10. Brown algae provide food and
habitat for marine organisms, and they are also important to humans.
a.
Brown algae are harvested for human food and for fertilizer in several parts of
the world.
b. They are a source of algin, a pectin-like substance added to
give foods a stable, smooth consistency.
11. Most have an alternation of generations
life cycle.
12. Fucus is an intertidal rockweed; meiotic cell division
produces gametes and adult is always diploid.


  
1,968,000,000 YBN
308) Chromalveolate Heterokont, Diatoms evolve.
Genetic comparison shows the ancestor
of the Chromalveolate Heterokont Diatoms evolving now.

Diatoms are diplontic.

Diatoms are a very common types of phytoplankton. Most diatoms are unicellular,
although some form chains or simple colonies. A characteristic feature of
diatom cells is that they are encased within a unique cell wall made of silica.
These walls show a wide diversity in form, some quite beautiful and ornate, but
usually consist of two symmetrical sides with a split between them, hence the
group name.

Life Cycle
When a cell divides each new cell takes as its epitheca a valve of the
parent frustule, and within ten to twenty minutes builds its own hypotheca;
this process may occur between one and eight times per day. Availability of
dissolved silica limits the rate of vegetative reproduction, but also because
this method progressively reduces the average size of the diatom frustule in a
given population there is a certain threshold at which restoration of frustule
size is neccesary. Auxospores are then produced, which are cells that posses a
different wall structure lacking the siliceous frustule and swell to the
maximum frustule size. The auxospore then forms an initial cell which forms a
new frustule of maximum size within itself.

KINGDOM Protista (Chromalveolata)
PHYLUM
Heterokontophyta
Colored groups
CLASS Bacillariophyceae (diatoms)

There are more than 200 genera of living diatoms, and it is estimated that
there are approximately 100 000 extant species (Round & Crawford, 1990).
Diatoms are a widespread group and can be found in the oceans, in freshwater,
in soils and on damp surfaces.

Their chloroplasts are typical of heterokonts, with four membranes and
containing pigments such as fucoxanthin. Individuals usually lack flagella, but
they are present in gametes and have the usual heterokont structure, except
they lack the hairs (mastigonemes) characteristic in other groups.

Most diatom species are non-motile but some are capable of an oozing motion. As
their relatively dense cell walls cause them to readily sink, planktonic forms
in open water usually rely on turbulent mixing of the upper layers by the wind
to keep them suspended in sunlit surface waters. Some species actively regulate
their buoyancy to counter sinking.

Diatoms cells are contained within a unique silicate (silicic acid) cell wall
comprised of two separate valves (or shells). The biogenic silica that the cell
wall is composed of is synthesised intracellularly by the polymerisation of
silicic acid monomers. This material is then extruded to the cell exterior and
added to the wall. Diatom cell walls are also called frustules or tests, and
their two valves typically overlap one other like the two halves of a petri
dish. In most species, when a diatom divides to produce two daughter cells,
each cell keeps one of the two valves and grows a smaller valve within it. As a
result, after each division cycle the average size of diatom cells in the
population gets smaller. Once such cells reach a certain minimum size, rather
than simply divide vegetatively, they reverse this decline by forming an
auxospore. This expands in size to give rise to a much larger cell, which then
returns to size-diminishing divisions. Auxospore production is almost always
linked to meiosis and sexual reproduction.

Diatoms are traditionally divided into two orders: centric diatoms (Centrales),
which are radially symmetric, and pennate diatoms (Pennales), which are
bilaterally symmetric. The former are paraphyletic to the latter. A more recent
classification is that of Round & Crawford (1990), who divide the diatoms into
three classes: centric diatoms (Coscinodiscophyceae), pennate diatoms without a
raphe (Fragilariophyceae), and pennate diatoms with a raphe
(Bacillariophyceae). It is probable there will be further revisions as our
understanding of their relationships increases.

Planktonic forms in freshwater and marine environments typically exhibit a
"bloom and bust" lifestyle. When conditions in the upper mixed layer (nutrients
and light) are favourable (e.g. at the start of spring) their competitive edge
(Furnas, 1990) allows them to quickly dominate phytoplankton communities
("bloom").

When conditions turn unfavourable, usually upon depletion of nutrients, diatom
cells typically increase in sinking rate and exit the upper mixed layer
("bust"). This sinking is induced by either a loss of buoyancy control, the
synthesis of mucilage that sticks diatoms cells together, or the production of
heavy resting spores.

In the open ocean, the condition that typically causes diatom (spring) blooms
to end is a lack of silicon. Unlike other nutrients, this is only a major
requirement of diatoms so it is not regenerated in the plankton ecosystem as
efficiently as, for instance, nitrogen or phosphorus nutrients. This can be
seen in maps of surface nutrient concentrations - as nutrients decline along
gradients, silicon is usually the first to be exhausted (followed normally by
nitrogen then phosphorus).

Heterokont chloroplasts appear to be derived from those of red algae, rather
than directly from prokaryotes as occurs in plants. This suggests they had a
more recent origin than many other algae. However, fossil evidence is scant,
and it is really only with the evolution of the diatoms themselves that the
heterokonts make a serious impression on the fossil record.

The earliest known fossil diatoms date from the early Jurassic (~185 Ma;
Kooistra & Medlin, 1996), although recent genetic (Kooistra & Medlin, 1996) and
sedimentary (Schieber, Krinsley & Riciputi, 2000) evidence suggests an earlier
origin. Medlin et al. (1997) suggest that their origin may be related to the
end-Permian mass extinction (~250 Ma), after which many marine niches were
opened. The gap between this event and the time that fossil diatoms first
appear may indicate a period when diatoms were unsilicified and their evolution
was cryptic (Raven & Waite, 2004). Since the advent of silicification, diatoms
have made a significant impression on the fossil record, with major deposits of
fossil diatoms found as far back as the early Cretaceous, and some rocks
(diatomaceous earth, diatomite, kieselguhr) being composed almost entirely of
them.
Although the diatoms may have existed since the Triassic, the timing of
their ascendancy and "take-over" of the silicon cycle is more recent.


3. Diatoms are the most numerous unicellular algae in the oceans. (Fig.
30.6a)
4. They are extremely numerous and an important source of food and O2
in aquatic systems.
5. Diatom cell walls consist of two silica-impregnated
halves or valves.
a. When diatoms reproduce asexually, each received one
old valve.
b. The new valve fits inside the old one; therefore, the new
diatom is smaller than the original one.
c. This continues until they
are about 30 percent of their original size.
d. Then they reproduce
sexually; a zygote grows and divides mitotically to form diatoms of normal
size.
6. The cell wall has an outer layer of silica (glass) with a variety of
markings formed by pores.
7. Diatom remains accumulate on the ocean floor and
are mined as diatomaceous earth for use as filters,
abrasives, etc.

Life Cycle (cont.)
Many neritic planktonic diatoms alternate between a vegetative
reproductive phase and a thicker walled resting cyst or statospore stage. The
siliceous resting spore commonly forms after a period of active vegetative
reproduction when nutrient levels have been depleted. Statospores may remain
entirely within the the parent cell, partially within the parent cell or be
isolated from it. An increase in nutreint levels and/or length of daylight
cause the statospore to germinate and return to its normal vegatative state.
Seasonal upwelling is therefore a vital part of many diatoms life cycle as a
provider of nutrients and as a transport mechanism which brings statospores or
their vegetative products up into the photic zone.
The resting spore morphology of
some species is similar to that of the corresponding vegetative cell, whereas
in other species the resting spores and the vegetative cells differ strongly.
The two valves of a resting spore may be similar or distinctly different. Often
the first valve formed is more similar to the valves of the vegetative cells
than the second valve.


  
1,967,000,000 YBN
309) Chromalveolate Heterokont, Water molds (Oomycetes OemISETEZ) evolve.
Genetic
comparison shows the ancestor of the Chromalveolate Heterokont Water molds
(Oomycetes OemISETEZ) evolving now.

Oomycetes (Water molds), with about 580 species, vary from unicellular, to
multicellular highly brached filamentous forms. The filamentous form is
called "coenocytic" (grows as a large multinucleate cell that results from
multiple nuclear divisions without cell divisions, also called "mycelium" in
fungi) Oomycetes grow by closed (or nearly closed) mitosis with pairs of
centrioles near the poles . Filamentous forms grow by mitosis, but only the
nucleus is duplicated (karyokinesis), no septa (horizontal cell wall) is
constructed, making these multinucleate very large single cells. Technically,
filamentous oomycetes are 3 celled multicellular organisms because a septa
forms between the vegetative filament and the diploid sporangium (and oogonium)
cells (and the haploid antheridium multinucleate cells are not free swimming),
but many people label oomycetes as single celled organism. But it appears
clear that oomycetes would be constructed of many cells if a cell wall was
built at mitosis. Sexual forms are diploid and reproduce by conjugation.

Water Molds are microscopic organisms that reproduce both sexually and
asexually and are composed of mycelia, or a tube-like vegetative body (all of
an organism's mycelia are called its thallus). The name "water mould" refers to
the fact that they thrive under conditions of high humidity and running surface
water.

Water molds were originally classified as fungi, but are now known to have
developed separately and show a number of differences. Their cell walls are
composed of cellulose rather than chitin and lack septa (a wall that divides
two spaces) except where reproductive cells are produced, in addition to having
gene sequences more closely related to brown algae than fungi. Also, in the
vegetative state they have diploid nuclei, whereas fungi have haploid nuclei.

The oomycetes include the water molds, white rusts and the downy mildews. Many
oomycetes are multinucleate filaments (hyphae) that resemble fungi. These
hyphae have no cross walls, but are one long hollow tube and are called
"coenocytic". They were once thought to be related to the fungi, but their cell
walls are made of cellulose, not chitin as they are in the true fungi. The
superficial resemblance of the fungi and the oomycetes is likely a case of
convergent evolution. Both groups have a filamentous (hyphal) body form with a
high surface area to volume ration which facilitates uptake of nutrients from
their surroundings.

The oomycetes are saprobic and parasitic forms, including water molds like
Saprolegnia and downey mildews like Peronospora.

1. These organisms (and slime molds) resemble fungi but all have
flagellated cells which fungi never do.
2. Water molds possess a cell wall
but it is made of cellulose, not chitin as in fungi.
3. Water molds produce
diploid (2n) zoospores and meiosis produces the gametes.

2. Aquatic water molds parasitize fishes, forming furry growths on
their gills, and decompose remains.
3. Terrestrial water molds parasitize
insects and plants; a water mold caused the 1840s Irish potato famine.
4. Water
molds have a filamentous body but cell walls are composed largely of
cellulose.
5. During asexual reproduction, they produce diploid motile spores (2n
zoospores) with flagella.
6. Unlike fungi, the adult is diploid; gametes are
produced by meiosis.
7. Eggs are produced in enlarged oogonia.

KINGDOM Protista
(Chromalveolata)
PHYLUM Heterokontophyta
Colorless groups
CLASS Oomycetes (water moulds)

Oomycetes have mitochondria with tubular christae.

Water mould motile cells are produced as asexual spores called zoospores, which
capitalize on surface water (including precipitation on plant surfaces) for
movement. The Zoospores have 2 unequal anterior (apical) flagella. They also
produce sexual spores, called oospores, that are translucent double-walled
spherical structures used to survive adverse environmental conditions.

The water molds are among the most important plant pathogenic (capable of
causing disease) organisms that may be facultatively or obligately parasitic.
The majority can be divided into three groups, although more exist.

* The Phytophthora group is a genus that causes diseases such as dieback,
potato blight (caused the potato famine in Ireland), sudden oak death and
rhododendron root rot.

* The Pythium group is a genus that is more ubiquitous than Phytophythora
and individual species have larger host ranges, usually causing less damage.
Pythium damping off is a very common problem in greenhouses where the organism
kills newly emerged seedlings. Mycoparasitic members of this group (e.g. P.
oligandrum) parasitise other oomycetes and fungi and have been employed as
biocontrol agents . One Pythium species, Pythium insidiosum is also known to
infect mammals.

* The third group are the downy mildews, which are easily identifable by
the appearance of white "mildew" on leaf surfaces (although this group can be
confused with the unrelated powdery mildews).


A male nuclei from a multinucleate haploid cell is transfered to into the
haploid egg cell; the male gamete is not free moving, only the female gametes
are although contained within the oogonium.


  
1,966,000,000 YBN
310) Chromalveolate Alveolata (Ciliates, Dinoflagellates, Apicomplexans)
evolve.

Genetic comparison shows the ancestor of the Chromalveolate Alveolata
(Ciliates, Dinoflagellates, Apicomplexans) evolving now.

The alveolates are a major line of protists. There are three main groups, which
are very divergent in form, but are now known to be close relatives based on
various ultrastructural and genetic similarities:
Ciliates Very common protozoa, with many
short cilia arranged in rows
Apicomplexa Parasitic protozoa that lack locomotive
structures except in gametes
Dinoflagellates Mostly marine flagellates, many of which
have chloroplasts

The most notable shared characteristic is the presence of cortical alveoli,
flattened vesicles packed into a continuous layer supporting the membrane,
typically forming a flexible pellicle. In dinoflagellates they often form armor
plates. Alveolates have mitochondria with tubular cristae, and their flagella
or cilia have a distinct structure.

The Apicomplexa and dinoflagellates may be more closely related to each other
than to the ciliates. Both have plastids, and most share a bundle or cone of
microtubules at the top of the cell. In apicomplexans this forms part of a
complex used to enter host cells, while in some colorless dinoflagellates it
forms a peduncle used to ingest prey.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa
(Goldfuss, 1818) R. Owen, 1858 - protozoa
SUBKINGDOM Biciliata
INFRAKINGDOM Alveolata
Cavalier-Smith, 1991
PHYLUM Myzozoa Cavalier-Smith & Chao, 2004
PHYLUM
Ciliophora (Doflein, 1901) Copeland, 1956 - ciliates


Relationships between some of these the major groups were suggested during the
1980s, and between all three by Cavalier-Smith, who introduced the formal name
Alveolata in 1991. They were confirmed by a genetic study by Gajadhar et al.
Some studies suggested the haplosporids, mostly parasites of marine
invertebrates, might belong here but they lack alveoli and are now placed among
the Cercozoa.

The development of plastids among the alveolates is uncertain. Cavalier-Smith
proposed the alveolates developed from a chloroplast-containing ancestor, which
also gave rise to the Chromista (the chromalveolate hypothesis). However, as
plastids only appear in relatively advanced groups, others argue the alveolates
originally lacked them and possibly the dinoflagellates and Apicomplexa
acquired them separately.


  
1,964,000,000 YBN
312) Ciliates evolve.
Genetic comparison shows the ancestor of the Chromalveolate
Alveolata Ciliates evolving now.

The ciliates are one of the most important groups of protists, common almost
everywhere there is water - lakes, ponds, oceans, and soils, with many ecto-
(lives on host) and endosymbiotic (lives in host) members, as well as some
obligate (depends on host for survival) and opportunistic parasites (does not
depend on host for survival). Ciliates tend to be large protists, a few
reaching 2 mm in length, and are some of the most complex in structure. The
name ciliate comes from the presence of hair-like organelles called cilia,
which are identical in structure to flagella but typically shorter and present
in much larger numbers. Cilia occur in all members of the group, although the
peculiar suctoria only have them for part of the life-cycle, and are variously
used in swimming, crawling, attachment, feeding, and sensation.

Unlike other eukaryotes, ciliates have two different sorts of nuclei: a small,
diploid micronucleus (reproduction), and a large, polyploid macronucleus
(general cell regulation). The latter is generated from the micronucleus by
amplification of the genome and heavy editing. The high degree of polyploidi
allows the cell to sustain an appropriate level of transcription. Division of
the macronucleus does not occur by a mitotic process but segregation of the
chromosomes is by a different process, whose mechanism is unknown. This
process is not perfect, and after about 200 generations the cell shows signs of
aging (has so many mutations that it does not function properly). Periodically
the macronuclei is (must be?) regenerated from the micronuclei. In most, this
occurs during sexual reproduction, which is not usually through syngamy but
through conjugation. Here two cells line up, the micronuclei undergo meiosis,
some of the haploid daughters are exchanged and then fuse to form new micro-
and macronuclei.

With a few exceptions, there is a distinct cytostome or mouth where ingestion
takes place. Food vacuoles are formed through phagocytosis and typically follow
a particular path through the cell as their contents are digested and broken
down via lysosomes so the substances the vacuole contains are then small enough
to diffuse through the membrane of the food vacuole into the cell. Anything
left in the food vacuole by the time it reaches the cytoproct (anus) is
discharged via exocytosis. Most ciliates also have one or more prominent
contractile vacuoles, which collect water and expel it from the cell to
maintain osmotic pressure, or in some function to maintain ionic balance. These
often have a distinctive star-shape, with each point being a collecting tube.

Most ciliates feed on smaller organisms (heterotrophic), such as bacteria and
algae, and detritus swept into the mouth by modified oral cilia. These usually
include a series of membranelles to the left of the mouth and a paroral
membrane to its right, both of which arise from polykinetids, groups of many
cilia together with associated structures. This varies considerably, however.
Some ciliates are mouthless and feed by absorption, while others are predatory
and feed on other protozoa and in particular on other ciliates. This includes
the suctoria, which feed through several specialized tentacles.

Ciliates and Amoeboids have in common:
Food is digested in food vacuoles.
Excess water is
expelled by contractile vacuoles.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa
(Goldfuss, 1818) R. Owen, 1858 - protozoa
SUBKINGDOM Biciliata
INFRAKINGDOM Alveolata
Cavalier-Smith, 1991
PHYLUM Ciliophora (Doflein, 1901) Copeland, 1956 -
ciliates
CLASS Karyorelictea
CLASS Heterotrichea
CLASS Spirotrichea
CLASS Litostomatea
CLASS
Phyllopharyngea
CLASS Nassophorea
CLASS Colpodea {possibly in phylum percolozoa}
CLASS
Prostomatea
CLASS Oligohymenophorea
CLASS Plagiopylea

In some forms there are also body polykinetids, for instance, among the
spirotrichs where they generally form bristles called cirri. More often body
cilia are arranged in mono- and dikinetids, which respectively include one and
two kinetosomes (basal bodies), each of which may support a cilium. These are
arranged into rows called kineties, which run from the anterior to posterior of
the cell. The body and oral kinetids make up the infraciliature, an
organization unique to the ciliates and important in their classification, and
include various fibrils and microtubules involved in coordinating the cilia.

The infraciliature is one of the main component of the cell cortex. Another are
the alveoli, small vesicles under the cell membrane that are packed against it
to form a pellicle maintaining the cell's shape, which varies from flexible and
contractile to rigid. Numerous mitochondria and extrusomes are also generally
present. The presence of alveoli, the structure of the cilia, the form of
mitosis and various other details indicate a close relationship between the
ciliates, Apicomplexa, and dinoflagellates. These superficially dissimilar
groups make up the alveolates.

Ciliates move by coordinated strokes of hundreds of cilia projecting through
holes in a semirigid pellicle.
They discharge long, barbed trichocysts for defense and
for capturing prey; toxicysts release a poison.
Most are holozoic and ingest food
through a gullet and eliminate wastes through an anal pore.
During asexual
reproduction, ciliates divide by transverse binary fission.
Ciliates possess two types
of nuclei-a large macronucleus and one or more small micronuclei.
a. The macronucleus
controls the normal metabolism of the cell.
b. The micronucleus are involved in
sexual reproduction.
1) The macronucleus disintegrates and the micronucleus undergoes
meiosis.
2) Two ciliates then exchange a haploid micronucleus.
3) The micronuclei give rise
to a new macronucleus containing only housekeeping genes.
Ciliates are diverse.
a. Members of
the genus Paramecium are complex. (Fig. 30.13b)
b. The barrel-shaped didinia expand
to consume paramecia much larger than themselves.
c. Suctoria rest on a stalk and
paralyze victims, sucking them dry.
d. Stentor resembles a giant blue vase with
stripes. (Fig. 30.13a)

Could the 2 nuclei in ciliates be the result of an earlier fusion (or
engulfing) of 2 prokaryotes?


  
1,963,000,000 YBN
313) Dinoflagellates evolve.
Genetic Ribosomal RNA comparison shows Chromalveolate
Alveolata, Dinoflagellates evolve.
Dinoflagellates reproduce mainly by haploid mitosis,
but also reproduce sexually.

In dinoflagellates, the chromosomes are always visible and do not condense
prior to mitosis. The chromosomes are attached to the nuclear envelope, which
persists during mitosis.

The main method of reproduction of the dinoflagellates is by longitudinal cell
division, with each daughter cell receiving one of the flagella ad a portion of
the theca and then constructing the missing parts in a very intricate sequence.
Some nonmotile species form zoospores, which may be colonial. A number of
species reproduce sexually, mostly by isogamy, but a few species reproduce by
heterogamy (anisogamy).

Dinoflagellate zygotes are similar to some acritarchs (early eukaryote
fossils).

Some Dinoflagellates produce cysts.

The dinoflagellates are a large group of flagellate protists. Most are marine
plankton, but they are common in fresh water habitats as well; their
populations are distributed depending on temperate, saltiness, or depth. About
half of all dinoflagellates are photosynthetic, and these make up the largest
group of eukaryotic algae aside from the diatoms. Being primary producers make
them an important part of the food chain. Some species, called zooxanthellae,
are endosymbionts of marine animals and protozoa, and play an important part in
the biology of coral reefs. Other dinoflagellates are colorless predators on
other protozoa, and a few forms are parasitic.

Some dinoflagellates are reported to be filamentous (multicellular).
Mitochondri
a christae are tubular.
Dinoflagellates are haploid (haplontic).

DOMAIN
Eukaryota - eukaryotes
KINGDOM Protozoa (Goldfuss, 1818) R. Owen, 1858 - protozoa
SUBKINGDOM
Biciliata
INFRAKINGDOM Alveolata Cavalier-Smith, 1991
PHYLUM Dinoflagellata
Bütschli, 1885
CLASS Dinophyceae (Bütschli, 1885) Pascher, 1914

CLASS Blastodiniophyceae Fensome et al., 1993
CLASS Noctiluciphyceae
Fensome et al., 1993
CLASS Syndiniophyceae Loeblich III, 1976

Most dinoflagellates are unicellular forms with two dissimilar flagella. One of
these extends towards the posterior, called the longitudinal flagellum, while
the other forms a lateral circle, called the transverse flagellum. In many
forms these are set into grooves, called the sulcus and cingulum. The
transverse flagellum provides most of the force propelling the cell, and often
imparts to it a distinctive whirling motion, which is what gives the name
dinoflagellate refers to (Greek dinos, whirling). The longitudinal acts mainly
as the steering wheel, but providing little propulsive force as well.

Dinoflagellates have a complex cell covering called an amphiesma, composed of
flattened vesicles, called alveoli. In some forms, these support overlapping
cellulose plates that make up a sort of armor called the theca. These come in
various shapes and arrangements, depending on the species and sometimes stage
of the dinoflagellate. Fibrous extrusomes are also found in many forms.
Together with various other structural and genetic details, this organization
indicates a close relationship between the dinoflagellates, Apicomplexa, and
ciliates, collectively referred to as the alveolates.

The chloroplasts in most photosynthetic dinoflagellates are bound by three
membranes, suggesting they were probably derived from some ingested alga, and
contain chlorophylls a and c and fucoxanthin, as well as various other
accessory pigments. However, a few have chloroplasts with different
pigmentation and structure, some of which retain a nucleus. This suggests that
chloroplasts were incorporated by several endosymbiotic events involving
already colored or secondarily colorless forms. The discovery of plastids in
Apicomplexa have led some to suggest they were inherited from an ancestor
common to the two groups, but none of the more basal lines have them.

All the same, the dinoflagellate still consists of the more common organelles
such as rough and smooth endoplasmic reticulum, Golgi apparatus, mitochondria,
lipid and starch grains, and food vacuoles. Some have even been found with
light sensitive organelle such as the eyespot or a larger nucleus containing a
prominent nucleolus.

Life-cycle
Dinoflagellates have a peculiar form of nucleus, called a dinokaryon, in which
the chromosomes are attached to the nuclear membrane. These lack histones and
remained condensed throughout interphase rather than just during mitosis, which
is closed and involves a unique external spindle. This sort of nucleus was once
considered to be an intermediate between the nucleoid region of prokaryotes and
the true nuclei of eukaryotes, and so were termed mesokaryotic, but now are
considered advanced rather than primitive traits.

In most dinoflagellates, the nucleus is dinokaryotic throughout the entire life
cycle. They are usually haploid, and reproduce primarily through fission, but
sexual reproduction also occurs. This takes place by fusion of two individuals
to form a zygote, which may remain mobile in typical dinoflagellate fashion or
may form a resting cyst, which later undergoes meiosis to produce new haploid
cells.

However, when the conditions become desperate, usually starvation or no light,
their normal routines change dramatically. Two dinoflagellates will fuse
together forming a planozygote. Next is a stage not much different from
hibernation called hypnozygote when the organism takes in excess fat and oil.
At the same time its shape is getting fatter and the shell gets harder.
Sometimes even spikes are formed. When the weathers allows it, these
dinoflagellates break out of their shell and are in a temporary stage,
planomeiocyte, when they quickly reforms their individual thecas and return to
the dinoflagellates at the beginning of the process.

Ecology and fossils
Dinoflagellates sometimes bloom in concentrations of more than a
million cells per millilitre. Some species produce neurotoxins, which in such
quantities kill fish and accumulate in filter feeders such as shellfish, which
in turn may pass them on to people who eat them. This phenomenon is called a
red tide, from the color the bloom imparts to the water. Some colorless
dinoflagellates may also form toxic blooms, such as Pfiesteria. It should be
noted that not all dinoflagellate blooms are dangerous. Bluish flickers visible
in ocean water at night often come from blooms of bioluminescent
dinoflagellates, which emit short flashes of light when disturbed.

Dinoflagellate cysts are found as microfossils from the Triassic period, and
form a major part of the organic-walled marine microflora from the middle
Jurassic, through the Cretaceous and Cenozoic to the present day. Arpylorus,
from the Silurian of North Africa was at one time considered to be a
dinoflagellate cyst, but this palynomorph is now considered to be part of the
microfauna. It is possible that some of the Paleozoic acritarchs also represent
dinoflagellates.

Chloroplast features:
Chloroplasts: Brown
Mitochondria christae are tubular.


Nuclear features:
Gamete type: flagellated
Dinoflagellates are haploid
(haplontic).
has condensed chromosomes.
Mitotic spindle: external.
polar
structures: none, and centrioles

Flagellar features:
Number of flagella: 2
Heterokont, isokont, or anisokont:
anisokont
shaft features: paraxial rod, hairs
flagellate stages: gamete,
trophic, zoospore
trophic: (trophozoites) The activated, feeding stage in
the life cycle of protozoan parasites.
A protozoan, especially of the class
Sporozoa, in the active stage of its life cycle.
The feeding stage of a
protozoan (as distinct from reproductive or encysted stages).
zoospore: A
zoospore is a motile asexual spore utilizing a flagellum for locomotion. Also
called a swarm spore, these spores are used by some algae and fungi to
propagate themselves.

Golgi type: dictyosome

Food stores:
carbohydrate: alpha 1-4 glucan
fat=yes

extrusomes: tricocysts, nematocysts

eyespot type: cytoplasmic stigma, ?

Life Forms:
unicellular: flagellate, amoeboid, coccoid
multicellular:
filementous

Cell covering: pellicle with plates.


  
1,962,000,000 YBN
314) Apicomplexans evolve.
Genetic comparison shows Apicomplexans evolve.
The
Apicomplexa are a large group of protozoa, characterized by the presence of an
apical complex at some point in their life-cycle. They are exclusively
parasitic, and completely lack flagella or pseudopods except for certain gamete
stages. Diseases caused by Apicomplexa include:

* Babesiosis (Babesia)
* Cryptosporidiosis (Cryptosporidium)
* Malaria (Plasmodium)
* Toxoplasmosis
(Toxoplasma gondii)

Most members have a complex life-cycle, involving both asexual and sexual
reproduction. Typically, a host is infected by ingesting cysts, which divide to
produce sporozoites that enter its cells. Eventually, the cells burst,
releasing merozoites which infect new cells. This may occur several times,
until gamonts are produced, forming gametes that fuse to create new cysts.
There are many variations on this basic pattern, however, and many Apicomplexa
have more than one host.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa (Goldfuss, 1818) R.
Owen, 1858 - protozoa
SUBKINGDOM Biciliata
INFRAKINGDOM Alveolata Cavalier-Smith, 1991

PHYLUM Apicomplexa
CLASS Conoidasida Levine, 1988
CLASS Aconoidasida
Mehlhorn, Peters & Haberkorn, 1980
CLASS Metchnikovellea Weiser, 1977

CLASS Blastocystea Cavalier-Smith, 1998


  
1,961,000,000 YBN
89) Genetic comparison shows Rhizaria (the Phyla "Radiolaria", "Cercozoa", and
"Foraminifera") evolve now.

This marks the beginning of the protists described as "amoeboid", because they
have pseudopods.

5. Amoeboids phagocytize their food; pseudopods surround and engulf
prey.
6. Food is digested inside food vacuoles.
7. Freshwater amoeboids have contractile
vacuoles to eliminate excess water.

Some foraminifera are haplodiploid (alternate between haploid and diploid
cycles that both have mitosis).

The Rhizaria are a major line of protists. They vary considerably in form, but
for the most part they are amoeboids with filose, reticulose, or
microtubule-supported pseudopods. Many produce shells or skeletons, which may
be quite complex in structure, and these make up the vast majority of protozoan
fossils. Nearly all have mitochondria with tubular cristae.
There are three
main groups of Rhizaria:
Cercozoa Various amoebae and flagellates, usually with filose
pseudopods and common in soil
Foraminifera Amoeboids with reticulose pseudopods,
common as marine benthos
Radiolaria Amoeboids with axopods, common as marine plankton


The name Rhizaria was created recently by Cavalier-Smith in 2002. Most are
biciliate amoeboflagellates at some point in the life cycle. Pseudopodia are
root-like reticulopodia, filopodia and/or axopodia - not broad lobopodia as in
Amoeba. All of these features can, however, be found in members of other
clades. Nevertheless, the Rhizaria are supported by both rRNA and actin trees
(Cavalier-Smith & Chao, 2003; Nikolaev et al. 2004).

A few other groups may be
included in the Cercozoa, but on some trees appear closer to the Foraminifera.
These are the Phytomyxea and Ascetosporea, parasites of plants and animals
respectively, and the peculiar amoeba Gromia. The different groups of Rhizaria
are considered close relatives based mainly on genetic similarities, and have
been regarded as an extension of the Cercozoa. The name Rhizaria for the
expanded group was introduced by Cavalier-Smith in 2002, who also included the
centrohelids and Apusozoa.


  
1,961,000,000 YBN
320) Rhizaria Phylum "Cercozoa" evolve now.
The Cercozoa are a group of protists,
including most amoeboids and flagellates that feed by means of filose
pseudopods. These may be restricted to part of the cell surface, but there is
never a true cytostome or mouth as found in many other protozoa. They show a
variety of forms and have proven difficult to define in terms of structural
characteristics, although their unity is strongly supported by genetic studies.

The
best-known Cercozoa are the euglyphids, filose amoebae with shells of siliceous
scales or plates, which are commonly found in soils, nutrient-rich waters, and
on aquatic plants. Some other filose amoebae produce organic shells, including
the tectofilosids and Gromia. They were formerly classified with the euglyphids
as the Testaceafilosia. This group is not monophyletic, but nearly all studied
members fall in or near the Cercozoa, related to similarly shelled
flagellates.

Another important group placed here are the chlorarachniophytes, strange
amoebae that form a reticulating net. They are set apart by the presence of
chloroplasts, which apparently developed from an ingested green alga. They are
bound by four membranes and still possess a vestigial nucleus, called a
nucleomorph. As such, they have been of great interest to researchers studying
the endosymbiotic origins of organelles.

Other notable cercozoans include the cercomonads, which are common soil
flagellates. Two groups traditionally considered heliozoa, the dimorphids and
desmothoracids, belong here. Recently the marine Phaeodarea have also been
included. The Cercozoa are closely related to the Foraminifera and Radiolaria,
amoeboids that usually have complex shells, and together with them form a
supergroup called the Rhizaria. Their exact composition and relationships are
still being worked out.

PHYLUM Cercozoa (Cavalier-Smith 1998)
CLASS Spongomonadea
CLASS Proteomyxidea -
desmothoracids, dimorphids, gymnophryids, etc.
CLASS Sarcomonadea - cercomonads
CLASS
Imbricatea - euglyphids and thaumatomonads
CLASS Thecofilosea - tectofilosids and
cryomonads
CLASS Phaeodarea
CLASS Chlorarachnea (Hibberd & Norris, 1984)

Class Spongomonadea
Chlorarachniophytes are a small group of algae occasionally
found in tropical oceans. They are typically mixotrophic, ingesting bacteria
and smaller protists as well as conducting photosynthesis. Normally they have
the form of small amoebae, with branching cytoplasmic extensions that capture
prey and connect the cells together, forming a net. They may also form
flagellate zoospores, which characteristically have a single subapical
flagellum that spirals backwards around the cell body, and walled coccoid
cells.

The chloroplasts were presumably acquired by ingesting some green alga. They
are surrounded by four membranes, the outermost of which is continuous with the
endoplasmic reticulum, and contain a small nucleomorph between the middle two,
which is a remnant of the alga's nucleus. This contains a small amount of DNA
and divides without forming a mitotic spindle. The origin of the chloroplasts
from green algae is supported by their pigmentation, which includes
chlorophylls a and b, and by genetic similarities. The only other group of
algae that contain nucleomorphs are the cryptomonads, but their chloroplasts
seem to be derived from a red alga.

The chlorarachniophytes only include five genera, which show some variation in
their life-cycles and may lack one or two of the stages described above.
Genetic studies place them among the Cercozoa, a diverse group of amoeboid and
amoeboid-like protozoa.

Class Proteomyxidea
Order Desmothoracida (Hertwig & Lesser 1874)
The desmothoracids are a group
of heliozoan protists, usually sessile and found in freshwater environments.
Each adult is a spherical cell around 10-20 μm in diameter surrounded by a
perforated organic lorica or shell, with many radial pseudopods projecting
through the holes to capture food. These are supported by small bundles of
microtubules that arise near a point on the nuclear membrane. Unlike other
heliozoans, the microtubules are not in any regular geometric array, there does
not appear to be a microtubule organizing center, and there is no distinction
between the outer and inner cytoplasm.

Reproduction takes place by the budding off of small motile cells, usually with
two flagella. Later these are lost, and pseudopods and a lorica are formed.
Typically a single lengthened pseudopod will secrete a hollow stalk that
attached the adult to the substrate. The form of the flagella, the tubular
cristae within the mitochondria, and other characters led to the suggestion
that the desmothoracids belong among what is now the Cercozoa, which has now
been confirmed by genetic studies.

Order Heliomonadida
Genus Dimorpha
The dimorphids or heliomonads are a small group of heliozoa that
are unusual in possessing flagella throughout their life-cycle. There are two
genera: Dimorpha, a tiny organism found in freshwater, and the larger
Tetradimorpha, which is distinguished by having four rather than two flagella.
Bundles of microtubules, typically in square array, arise from a body near the
flagellar bases and support the numerous axopods that project from the cell
surface.

Dimorphids have a single nucleus, and mitochondria with tubular cristae.
Genetic studies place them among the Cercozoa, a group including various other
flagellates that form pseudopods.
Order Reticulosida
Family Gymnophryidae (Mikrjukov &
Mylnikov, 1996)
The gymnophryids are a small group of amoeboids that lack shells and
produce thin, reticulose pseudopods. These contain microtubules and have a
granular appearance, owing to the presence of extrusomes, but are distinct from
the pseudopods of Foraminifera. They are included among the Cercozoa, but
differ from other cercozoans in having mitochondria with flat cristae, rather
than tubular cristae.

Gymnophrys cometa, found in freshwater and soil, is representative of the
group. The cell body is under 10 μm in size, and has a pair of reduced
flagella, which are smooth and insert parallel to one another. It may also
produce motile zoospores and cysts. Gymnophrys and Borkovia are the only
confirmed genera, but other naked reticulose amoebae such as Biomyxa may be
close relatives.

Class Sarcomonadea
Order Cercomonadida (Poche, 1913)
Cercomonads are small flagellates, widespread
in aqueous habitats and especially common in soils. The cells are generally
around 10 μm in length, without any shell or covering. They produce filose
pseudopods to capture bacteria, but do not use them for locomotion, which
usually takes place by gliding along surfaces. Most members have two smooth
flagella, one directed forward and one trailing under the cell, inserted at
right angles near its anterior. The nucleus is connected to the flagellar bases
and accompanied by a characteristic paranuclear body.

Genetic studies place the cercomonads among the core Cercozoa, a diverse group
of amoeboid and flagellate protozoans. They are divided into two families. The
Heteromitidae tend to be relatively rigid, and produce only temporary
pseudopods. The Cercomonadidae are more plastic, and when food supplies are
plentiful may become amoeboid and even multinucleate. The classification of
genera and species continues to undergo revision. Some genera have been merged,
like Cercomonas and Cercobodo, and some have been moved to other groups.

Class Imbricatea
Order Euglyphida (Copeland, 1956)
The euglyphids are a prominent group of
filose amoebae that produce shells or tests from siliceous scales, plates, and
sometimes spines. These elements are created within the cell and then assembled
on its surface in a more or less regular arrangement, giving the test a
textured appearance. There is a single opening for the long slender pseudopods,
which capture food and pull the cell across the substrate.

Euglyphids are common in soils, marshes, and other organic-rich environments,
feeding on tiny organisms such as bacteria. The test is generally 30-100
μm in length, although the cell only occupies part of this space. During
reproduction a second shell is formed opposite the opening, so both daughter
cells remain protected. Different genera and species are distinguished
primarily by the form of the test. Euglypha and Trinema are the most common.

The euglyphids are traditionally grouped with other amoebae. However, genetic
studies instead place them with various amoeboid and flagellate groups, forming
an assemblage called the Cercozoa. Their closest relatives are the
thaumatomonads, flagellates that form similar siliceous tests.

Class Thecofilosea
Order Tectofilosida (Cavalier-Smith & Chao, 2003)
The tectofilosids or
amphitremids are a group of filose amoebae with shells. These are composed of
organic materials and sometimes collected debris, in contrast to the
euglyphids, which produce shells from siliceous scales. The shell usually has a
single opening, but in Amphitrema and a few other genera it has two on opposite
ends. The cell itself occupies most of the shell. They are most often found on
marsh plants such as Sphagnum.

This group was previously classified as the Gromiida or Gromiina. However,
molecular studies separate Gromia from the others, which must therefore be
renamed. They are placed among the Cercozoa, and presumably developed from
flagellates like Cryothecomonas, which has a similar test. However, only a few
have been studied in detail, so their relationships and monophyly are not yet
certain.

Class: Phaeodarea (Haeckel, 1879)
The Phaeodarea are a group of amoeboid protists.
They are traditionally considered radiolarians, but in molecular trees do not
appear to be close relatives of the other groups, and are instead placed among
the Cercozoa. They are distinguished by the structure of their central capsule
and by the presence of a phaeodium, an aggregate of waste particles within the
cell.

Phaeodarea produce hollow skeletons composed of amorphous silica and organic
material, which rarely fossilize. The endoplasm is divided by a cape with three
openings, of which one gives rise to feeding pseudopods, and the others let
through bundles of microtubules that support the axopods. Unlike other
radiolarians, there are no cross-bridges between them. They also lack symbiotic
algae, generally living below the photic zone, and do not produce any strontium
sulphate.

CLASS Chlorarachnea
Chlorarachniophytes are a small group of algae occasionally found in
tropical oceans. They are typically mixotrophic, ingesting bacteria and smaller
protists as well as conducting photosynthesis. Normally they have the form of
small amoebae, with branching cytoplasmic extensions that capture prey and
connect the cells together, forming a net. They may also form flagellate
zoospores, which characteristically have a single subapical flagellum that
spirals backwards around the cell body, and walled coccoid cells.

The chloroplasts were presumably acquired by ingesting some green alga. They
are surrounded by four membranes, the outermost of which is continuous with the
endoplasmic reticulum, and contain a small nucleomorph between the middle two,
which is a remnant of the alga's nucleus. This contains a small amount of DNA
and divides without forming a mitotic spindle. The origin of the chloroplasts
from green algae is supported by their pigmentation, which includes
chlorophylls a and b, and by genetic similarities. The only other group of
algae that contain nucleomorphs are the cryptomonads, but their chloroplasts
seem to be derived from a red alga.

The chlorarachniophytes only include five genera, which show some variation in
their life-cycles and may lack one or two of the stages described above.
Genetic studies place them among the Cercozoa, a diverse group of amoeboid and
amoeboid-like protozoa.


  
1,960,000,000 YBN
319) Rhizaria Phylum "Radiolaria" evolve now.
Ribosomal RNA indicates that Rhizaria
Phylum "Radiolaria" evolve now.

Radiolarians (also radiolaria) are amoeboid protozoa that produce intricate
mineral skeletons, typically with a central capsule dividing the cell into
inner and outer portions, called endoplasm and ectoplasm. They are found as
plankton throughout the ocean, and their shells are important fossils found
from the Cambrian onwards.

Move by pseudopodia.
external tests made of silica (glass).

Radiolaria have a test composed of silica or strontium sulfate.
Most have a radial
arrangement of spines.
Pseudopods (actinopods) project from an external layer of
cytoplasm and are supported by rows of microtubules.
Tests of dead foraminiferans and
radiolarians form deep layers of ocean floor sediment.
Back to the Precambrian, each
layer has distinctive foraminiferans which helps date rocks.
Over hundreds of millions
of years, the CaCO3 shells have contributed to the formation of chalk deposits
(i.e. White Cliffs of Dover, limestone of pyramids).

Lifecycle
Simple asexual fission of radiolarian cells has been observed. Sexual
reproduction has not been confirmed but is assumed to occur; possible
gametogenesis has been observed in the form of "swarmers" being expelled from
swellings in the cell. Swarmers are formed from the central capsule after the
ectoplasm has been discarded. The central capsule sinks through the water
column to depths hundreds of meters greater than the normal habitat and swells,
eventually rupturing and releasing the flagellated cells. Recombination of
these cells, which are assumed to be haploid, to produce diploid "adults" has
not been observed however and is only inferred to occur. Comparisons of
standing crops within the water column and sediment trap samples have
ascertained that the average life span of radiolarians is about two weeks,
ranging from a few days to a few weeks.

All radiolarians secrete strontium
sulphate at some point in the life cycle - as the adult shell in Acantharea,
and as crystals in ‘swarmer cells" produced during asexual reproduction in
Polycystinea.
Large, planktonic forms that produce a glassy, intricate shell.

Radiolarians have many needle-like pseudopods supported by microtubules, called
axopods, which aid in flotation. The nuclei and most other organelles are in
the endoplasm, while the ectoplasm is filled with frothy vacuoles and lipid
droplets, keeping them buoyant. Often it also contains symbiotic algae,
especially zooxanthellae, that provide most of the cell's energy. Some of this
organization is found among the heliozoa, but those lack central capsules and
only produce simple scales and spines.

The main class of radiolarians are the Polycystinea, which produce siliceous
skeletons. These include the majority of fossils. They also include the
Acantharea, which produce skeletons of strontium sulfate. Despite some initial
suggestions to the contrary, genetic studies place these two groups close
together. They also include the peculiar genus Sticholonche, which lacks an
internal skeleton and so is usually considered a heliozoan.

Traditionally the radiolarians also include the Phaeodarea, which produce
siliceous skeletons but differ from the polycystines in several other respects.
However, on molecular trees they branch with the Cercozoa, a group including
various flagellate and amoeboid protists. The other radiolarians appear near,
but outside, the Cercozoa, so the similarity is due to convergent evolution.
The radiolarians and Cercozoa are included within a supergroup called the
Rhizaria.

German biologist Ernst Haeckel produced exquisite (and perhaps somewhat
exaggerated) drawings of radiolaria, helping to popularize these protists among
Victorian parlor microscopists alongside foraminifera and diatoms.
PHYLUM
Radiolaria (Müller 1858 emend.)
CLASS Polycystinea
CLASS Acantharea
(Haeckel, 1881)
CLASS Sticholonchea
(CLASS Phaeodarea Haeckel, 1879 )?

CLASS Polycystinea:
The polycystines are a group of radiolarian protists. They include the
vast majority of the fossil radiolaria, as their skeletons are abundant in
marine sediments, making them one of the most common groups of microfossils.
These skeletons are composed of opaline silica. In some it takes the form of
relatively simple spicules, but in others it forms more elaborate lattices,
such as concentric spheres with radial spines or sequences of conical chambers.


Class Acantharea
The Acantharea are a small group of radiolarian protozoa, distinguished
mainly by their skeletons. These are composed of strontium sulfate crystals,
which do not fossilize, and take the form of either ten diametric or twenty
radial spines. The central capsule is made up of microfibrils arranged into
twenty plates, each with a hole through which one spine projects, and there is
also a microfibrillar cortex linked to the spines by myonemes. These assist in
flotation, together with the vacuoles in the ectoplasm, which often contain
zooxanthellae.
The axopods are fixed in number. Reproduction takes place by
formation of spores, which may be flagellate. These develop into mononucleate
amoebae; adults are usually multinucleate.

Class Sticholonchea
Sticholonche is a peculiar genus of protozoan with a single species, S.
zanclea, found in open oceans at depths of 100-500 metres. It is generally
considered a heliozoan, placed in its own order, called the Taxopodida. However
it has also been classified as an unusual radiolarian, and this has gained
support from genetic studies, which place it near the Acantharea.

Sticholonche are usually around 200 μm, though this varies considerably,
and have a bilaterally symmetric shape, somewhat flattened and widened at the
front. The axopods are arranged into distinct rows, six of which lie in a
dorsal groove and are rigid, and the rest of which are mobile. These are used
primarily for buoyancy, rather than feeding. They also have fourteen groups of
prominent spines, and many smaller spicules, although there is no central
capsule as in true radiolarians.

Cercozoa, originally named by Cavalier-Smith in 1998, is a diverse group of
taxa united solely on molecular grounds, but supported by a number of genes
(Longet et al., 2003).

Amongst notable members of the Cercozoa are amoeboid forms such as Difflugia,
which produce agglutinated tests that may be fossilised (the record extends
back to the Neoproterozoic - Finlay et al., 2004), and the Chlorarachnea
(e.g. Chlorarachnion), marine amoeboid organisms which possess chloroplasts
derived from a secondary endosymbiosis with a green alga. Cavalier-Smith,
(2003). The nucleus of the endosymbiont in Chlorarachnion, in fact, has not
fully degraded as in most secondarily plastid-bearing eukaryotes, and the
chloroplast retains a small nucleomorph contained within the surrounding
membranes.

The Polycystinea (sometimes spelled Polycistinea or Polycystina) are one group
of the Radiolaria. These are not just "small shelly fauna," they are tiny
shelly fauna made up of single, if rather complex, cells. The shell turns out
to be made of amorphous silica -- essentially sand -- without the admixture of
organics that characterize similar forms. Polycystinea are exclusively marine
but found in great numbers in the oceans. Their fossil record goes back almost
a billion years, well into Precambrian time.

Like other radiolarians, the cytoplasm of Polycystinea is divided into
ectoplasm and endoplasm by a perforated protein capsule -- not the nuclear
membrane, but a novel structure unique to this group. The endoplasm forms a
central medulla enclosed by this porous, membranous capsule. The nucleus is
inside this central region. The ectoplasm is outside the capsule and forms the
region known as the cortex (or calymma). The visible remains shown in the image
are made up of perforated tests (the "shells"). In life, these are located in
the ectoplasm. Polycystinates extend pseudopods supported by a complex
microtubular array (axopods) which originate in the endoplasm. The pseudopods
pass through pores in the test and extend, covered with a thin layer of
cytoplasm, from the surface of the cell. Spines of the test, if any, also pass
through the capsule and extend, covered with cytoplasm, from the surface of the
cell. The ectoplasm is often vacuolated and frequently contains photosynthetic
zooxanthellae.

The endoplasm actually contains all of the organelles normally associated with
a "normal" heterotrophic eukaryotic cell, including mitochondria, a nucleus,
and a cytoskeleton. The ectoplasm is largely filled with digestive vacuoles,
symbiotic algae, and the test. From an evolutionary standpoint, the
Polycystina appear to be one step towards a whole different type of biological
organization based on a 3-compartment cell, rather than the 2-compartment cell
of metazoans. In fact, a number of polycystinean species are colonial. It is
interesting to speculate on what might have evolved on this model, had
circumstances been different.


  
1,960,000,000 YBN
321) Rhizaria Phylum "Foraminifera" evolve now.
Ribosomal RNA shows Rhizaria Phylum
"Foraminifera" (also known as "Granuloreticulosea") evolve now.

Forminifera are catagorized as amoeboid because they have pseudopods.

The Foraminifera, or forams for short, are a large group of amoeboid protists
with reticulating pseudopods, fine strands that branch and merge to form a
dynamic net. They typically produce a shell, or test, which can have either one
or multiple chambers, some becoming quite elaborate in structure. About 250 000
species are recognized, both living and fossil. They are usually less than 1 mm
in size, but some are much larger, and the largest recorded specimen reached 19
cm. As fossils, foraminifera are extremely useful.
Foraminifera are
haplodiploid.
Most have a kind of shell called a "test", which is composed of
calcium carbonate.

move by pseudopodia
most are marine
tests are major components of limestone
used
to date marine sediments.

Foraminifera, especially the calcareous forms, have a fossil record stretching
back to the Cambrian (Lee, 1990), and are especially important
biostratigraphically.

b. Foraminiferans have a multi-chambered CaCO3 (calcium carbonate)
shell; thin pseudopods extend through holes.

Of the approximately 4000 living species of foraminifera the life cycles of
only 20 or so are known. There are a great variety of reproductive, growth and
feeding strategies, however the alternation of sexual and asexual generations
is common throughout the group and this feature differentiates the foraminifera
from other members of the Granuloreticulosea. An asexually produced haploid
generation commonly form a large proloculus (initial chamber) and are therefore
termed megalospheric. Sexually produced diploid generations tend to produce a
smaller proloculus and are therefore termed microspheric. Importantly in terms
of the fossil record, many foraminiferal tests are either partially dissolved
or partially disintegrate during the reproductive process.The planktonic
foraminifera Hastigerina pelagica reproduces by gametogenesis at depth, the
spines, septa and apertural region are resorbed leaving a tell-tale test.
Globigerinoides sacculiferproduces a sac-like final chamber and additional
calcification of later chambers before dissolution of spines occurs, this again
produces a distinctive test, which once gametogenesis is complete sinks to the
sea bed. Since the meiosis products have to differentiate or mature into
gametes, meiosis does not result directly in gametes, these species are
haplodipoid (haplodiplontic).

Modern forams are primarily marine, although they can survive in
brackish conditions. A few species survive in fresh water (e.g. Lake Geneva)
and one species even lives in damp rainforrest soil. They are very common in
the meiobenthos, and about 40 species are planktonic. The cell is divided into
granular endoplasm and transparent ectoplasm. The pseudopodial net may emerge
through a single opening or many perforations in the test, and
characteristically has small granules streaming in both directions.

The pseudopods are used for locomotion, anchoring, and in capturing food, which
consists of small organisms such as diatoms or bacteria. A number of forms have
unicellular algae as endosymbionts, from diverse lineages such as the green
algae, red algae, golden algae, diatoms, and dinoflagellates. Some forams are
kleptoplastic, retaining chloroplasts from ingested algae to conduct
photosynthesis.

The foraminiferan life-cycle involves an alternation between haploid and
diploid generations, although they are mostly similar in form. The haploid or
gamont initially has a single nucleus, and divides to produce numerous gametes,
which typically have two flagella. The diploid or schizont is multinucleate,
and after meiosis fragments to produce new gamonts. Multiple rounds of asexual
reproduction between sexual generations is not uncommon.

The form and composition of the test is the primary means by which forams are
identified and classified. Most have calcareous tests, composed of calcium
carbonate, which generally takes the form of interlocking microscopic crystals,
giving it a glassy or hyaline appearance. In other forams the test may be
composed of organic material, made from small pieces of sediment cemented
together (agglutinated), and in one genus of silica. Openings in the test,
including those that allow cytoplasm to flow between chambers, are called
apertures.

Tests are known as fossils as far back as the Cambrian period, and many marine
sediments are composed primarily of them. For instance, the nummulitic
limestone that makes up the pyramids of Egypt is composed almost entirely of
them. Forams may also make a significant contribution to the overall deposition
of calcium carbonate in coral reefs.

Because of their diversity, abundance, and complex morphology, fossil
foraminiferal assembleages can give accurate relative dates for rocks and thus
are extremely useful in biostratigraphy. Before more modern techniques became
available, the oil industry relied heavily on microfossils such as foraminifera
to find potential oil deposits.

For the same reasons they make good biostratigraphic markers, living
foraminiferal assembleages have been used as bioindicators in coastal
environments, including as indicators of coral reef health.

Fossil foraminifera are also useful in paleoclimatology and paleoceanography.
They can be used to reconstruct past climate by examining their oxygen stable
isotope ratios. Geographic patterns seen in the fossil record of planktonic
forams are also used to reconstruct paleo ocean current patterns.

Genetic studies have identified the naked amoeba Reticulomyxa and the peculiar
xenophyophores as foraminiferans without tests. A few other ameoboids produce
reticulose pseudopods, and were formerly classified with the forams as the
Granuloreticulosa, but this is no longer considered a natural group, and most
are now placed among the Cercozoa. Both the Cercozoa and Radiolaria are close
relatives of the Foraminifera, together making up the Rhizaria, but the exact
position of the forams is still unclear.

PHYLUM Foraminifera
CLASS Athalamea (Haeckel, 1862)
CLASS Xenophyophorea (F.E. Schulze,
1904)
CLASS Foraminifera (Lee, 1990)


CLASS Foraminifera
ORDER Allogromiida
The Allogromiida are a small group of
foraminiferans, including those that produce organic tests (Lagynacea). Genetic
studies have shown that some foraminiferans with agglutinated tests, previously
included in the Textulariida or as their own order Astrorhizida, also belong
here. Allogromiids produce relatively simple tests, usually with a single
chamber, similar to those of other protists such as Gromia. They are found in
stressed environments, including both marine and freshwater forms, and are the
oldest forams known from the fossil record.
ORDER Fusulinida
The fusulinids are an
extinct group of foraminiferan protozoa. They produce calcareous shells, which
are of fine calcite granules packed closely together; this distinguishes them
from other calcareous forams, where the test is usually hyaline. Fusulinids are
important indicator fossils.
ORDER Globigerinida
The Globigerinida are a common group of
foraminiferans that are found as marine plankton (other groups are primarily
benthic). They produce hyaline calcareous tests, and are known as fossils from
the Jurassic period onwards. The group has included more than 100 genera and
over 400 species, of which about 30 species are extant. One of the most
important genera is Globigerina; vast areas of the ocean floor are covered with
Globigerina ooze (named by Murray and Renard in 1873), dominated by the shells
of planktonic forams.
ORDER Miliolida
The miliolids are a group of foraminiferans,
abundant in shallow waters such as estuaries and coastlines, though they also
include oceanic forms. They are distinguished by producing porcelaneous tests,
composed of calcite needles and organic material; the needles have a high
proportion of magnesium and are oriented randomly. The test lacks pores and
generally has multiple chambers, which are often arranged in a distinctive
fashion called milioline.
ORDER Rotaliida
The Rotaliida are a large and abundant group
of foraminiferans. They are primarily oceanic benthos, although some are common
in shallower waters such as estuaries. They also include many important
fossils, such as nummulites. Rotaliids produce hyaline tests, in which the
microscopic crystals may be oriented either radially (as in other forams) or
obliquely.
ORDER Textulariida
The Textulariida are a group of common foraminiferans that
produce agglutinated shells, composed of foreign particles in an organic or
calcareous cement. Previously they were taken to include all such species, but
genetic studies have shown that they are not all closely related, and several
superfamilies have been moved to the order Allogromiida. The remaining forms
are sometimes divided into three orders: the Trochamminida and Lituolida
(organic cement) and the Textulariida sensu stricto (calcareous cement). All
three are known as fossils from the Cambrian onwards.

CLASS Xenophyophorea
Xenophyophores are marine protozoans, giant single-celled organisms found
throughout the world's oceans, but in their greatest numbers on the abyssal
plains of the deep ocean. They were first described as sponges in 1889, then as
testate amoeboids, and later as their own phylum of Protista. A recent genetic
study suggested that the xenophyophores are a specialized group of
Foraminifera. There are approximately 42 recognized species in 13 genera and 2
orders; one of which, Syringammina fragillissima, is among the largest known
protozoans at a maximum 20 centimetres in diameter.

Abundant but poorly understood, xenophyophores are delicate organisms with a
variable appearance; some may resemble flattened discs, angular four-sided
shapes (tetrahedra), or like frilly or spherical sponges. Local environmental
conditions-such as current direction and speed-may play a part in influencing
these forms. Xenophyophores are essentially lumps of viscous fluid called
cytoplasm containing numerous nuclei distributed evenly throughout. Everything
is contained in a ramose system of tubes called a granellare, itself composed
of an organic cement-like substance.

As benthic deposit feeders, xenophyophores tirelessly root through the muddy
sediments on the sea floor. They excrete a slimy substance whilst feeding; in
locations with a dense population of xenophyophores, such as at the bottoms of
oceanic trenches, this slime may cover large areas. Local population densities
may be as high as 2,000 individuals per 100 square metres, making them dominant
organisms in some areas. These giant protozoans seem to feed in a manner
similar to amoebas, enveloping food items with a foot-like structure called a
pseudopodium. Most are epifaunal (living atop the seabed), but one species
(Occultammina profunda), is known to be infaunal; it buries itself up to 6 cm
deep into the sediment.

Their glue-like secretions cause silt and strings of their own fecal matter,
called stercomes, to build up into masses (called stercomares) on their
exteriors. In this way, the organisms form structures which project from the
sea floor; this characteristic also explains their name, which may be
translated from the Greek to mean "bearer of foreign bodies". A protective,
shell-like test is thereby agglutinated around the granellare, which is
composed of scavenged minerals and the microscopic skeletal remains of other
organisms, such as sponges, radiolarians, and other foraminiferans.

Xenophyophores may be an important part of the benthic ecosystem by virtue of
their constant bioturbation of the sediments, providing a habitat for other
organisms such as isopods. Research has shown that areas dominated by
xenophyophores have 3-4 times the number of benthic crustaceans, echinoderms,
and molluscs than equivalent areas which lack xenophyophores. The
xenophyophores themselves also play commensal host to a number of
organisms-such as isopods (e.g., genus Hebefustis), sipunculan and polychaete
worms, nematodes, and harpacticoid copepods-some of which may take up
semi-permanent residence within a xenophyophore's test. Brittle stars
(Ophiuroidea) also appear to have some sort of relationship with
xenophyophores, as they are consistently found directly underneath or on top of
the protozoans.

Xenophyophores are difficult to study due to their extreme fragility. Specimens
are invariably damaged during sampling, rendering them useless for captive
study or cell culture. For this reason, very little is known of their life
history. As they occur in all the world's oceans and in great numbers,
xenophyophores could be indispensable agents in the process of sediment
deposition and in maintaining biological diversity in benthic ecosystems.

Xenophyophores are large marine Amoebae containing barite (BaSO4) crystals.

CLASS Athalamea
Granuloreticulosea, lacking a test or shell, though some forms might be
covered by a thin lorica. Pseudopods could arise anywhere over the surface of
the body, and could be branched to a greater or lesser extent in different
representa-tives of the group, with or without anastomosing connections in the
pseudopodial network. Organisms that have not been examined by modern
techniques, nor have been seen in recent years, to check the fact that they do
have granular reticulopodial bidirectional streaming, have been removed from
this class and placed with the amoebae of uncertain affinities. One genus
remains: Reticulomyxa.


  
1,900,000,000 YBN
66) Oldest Acritarch (eucaryote) fossils.
These fossils are reported to be both in
Chuanlinggou Formation, China and in Russia.

Acritarchs, the name coined by Evitt in 1963 which means "of uncertain origin",
are an artificial group. The group includes any small (most are between 20-150
microns across), organic-walled microfossil which cannot be assigned to a
natural group. They are characterised by varied sculpture, some being spiny and
others smooth. They are believed to have algal affinities, probably the cysts
of planktonic eukaryotic algae. They are valuable Proterozoic and Palaeozoic
biostratigraphic and palaeoenvironmental tools.

Chitinozoa are large (50-2000
microns) flask-shaped palynomorphs which appear dark, almost opaque when viewed
using a light microscope. They are important Palaeozoic microfossils as
stratigraphic markers.

The oldest known Acritarchs are recorded from shales of Palaeoproterozoic
(1900-1600 Ma) age in the former Soviet Union. They are stratigraphically
useful in the Upper Proterozoic through to the Permian. From Devonian times
onwards the abundance of acritarchs appears to have declined, whether this is a
reflection of their true abundance or the volume of scientific research is
difficult to tell.


  
1,874,000,000 YBN
61) Oldest non-acritarch Eukaryote fossil Grypania spiralis (an alga 10 cm
long) from BIF in Michigan. Oldest algae fossil.

The date of this fossil was
originally 2100mybn, but Schneider measured the Marquette Range Supergroup
(MRS), A rhyolite in the Hemlock Formation, a mostly bimodal submarine
volcanic deposit that is laterally correlative with the Negaunee
Iron-formation, yields a sensitive high-resolution ion microprobe (SHRIMP) U-Pb
zircon age of 1874 ± 9 Ma.

In 1992, Han and Runnegar, finders of this fossil, compared the fossil to
Acetabularia, a single-celled green algae. If true, this would make Grypania
the oldest green algae fossil.




  
1,870,000,000 YBN
151) Amino acid sequence comparison shows the archaebacteria and eukaryote line
separating here at 1,870 mybn (first eukaryote, and first protist).


  
1,800,000,000 YBN
46) End of the Banded Iron Formation Rocks.



  
1,584,000,000 YBN
152) Amino acid sequence comparison shows Gram-negative and Gram-positive
eubacteria here at 1,584 mybn (first Gram-positive bacteria).


  
1,576,000,000 YBN
67) A eukaroyte cell forms a symbiotic relationship with cyanobacteria, which
form plastids (chloroplasts). Like mitochondria, these organelles copy
themselves and are not made by the cell DNA.

Depending on their morphology and
function, plastids are commonly classified as chloroplasts, leucoplasts,
amyloplasts or chromoplasts.



  
1,513,000,000 YBN
221) First fungi evolve.
Genetic comparison shows fungi evolving now. This begins the
fungi kingdom. Perhaps fungi evolved from the amoebozoa slime mold line,
because the sporangiophore (stalk) and sporangium (ball on top) of slime molds
look very similar to many fungi.



  
1,500,000,000 YBN
323) First plant (single cell, similar to glaucophytes) evolves.
Ribosomal RNA place
first plant (single cell, similar to glaucophytes) evolving here. This begins
the plant kingdom.

Cavelier-Smith and Ema E. -Y. Chao write: "Kingdom Plantae (sensuCavalier-Smith
1981) was originally defined as comprising all eukaryotes with chloroplasts
possessing an envelope of two membranes and mitochondria with (irregularly)
flat cristae. It originally included Viridaeplantae (green algae and
embryophyte or "higher" plants), Rhodophyta (red algae), and Glaucophyta (e.g.,
Cyanophora, Glaucocystis). It was argued that all three groups diverged from a
single primary symbiogenetic origin of plastids (Cavalier-Smith 1982). Both the
monophyly of plastids and that of Glaucophyta and Plantae long met unreasonably
strong opposition because of widespread false dogma that symbiogenesis is easy
and because the three taxa usually do not group together in 18S rRNA trees.
Now, however, derived features of all plastids compared with cyanobacteria and
numerous molecular trees have led to the acceptance of plastid monophyly
(Delwiche and Palmer 1998) and to the monophyly of glaucophyte algae.
Furthermore, a sister relation between red algae and Viridaeplantae is strongly
supported by concatenated protein trees for nuclei (Moreira et al. 2000;
Baldauf et al. 2000) and chloroplasts (Martin et al. 1998; Turmel et al. 1999).
The sister relationship between them and glaucophytes is convincingly, but
significantly more weakly, supported by the same trees. Thus the case of
Plantae shows that arguments from morphology and evolutionary considerations of
protein targeting during symbiogenesis (Cavalier-Smith 2000b) gave the correct
answer much more rapidly than single-gene trees, which still do not clearly
group all three taxa together. In all our trees in the present study (and the
recent tree of Edgcomb et al. 2002), Rhodophyta and Viridaeplantae are sisters,
but with weak support. Glaucophyta wander aimlessly from one place to another
in different trees."

Ribosomal RNA place first plant evolving here, although
glaucophytes, the earliest living plants (for many people) do not evolve until
later.


  
1,492,000,000 YBN
173) Roper Group eukaryote algea microfossils.


  
1,400,000,000 YBN
86) Glaucophyta evolve.
Genetic comparison shows Phylum Glaucophyta evolving at this
time.
Some people catagorize Glaucophyta in the kingdom Plantae instead of Protista,
and label glaucophyta the most ancient living plants.

The glaucophytes, also referred to as glaucocystophytes or glaucocystids, are a
tiny group of freshwater algae. They are distinguished mainly by the presence
of cyanelles, primitive chloroplasts which closely resemble cyanobacteria and
retain a thin peptidoglycan wall between their two membranes.

It is thought that the green algae (from which the higher plants evolved), red
algae and glaucophytes acquired their chloroplasts from endosymbiotic
cyanobacteria. The other types of algae received their chloroplasts through
secondary endosymbiosis, by engulfing one of those types of algae along with
their chloroplasts.

The glaucophytes are of obvious interest to biologists studying the development
of chloroplasts: if the hypothesis that primary chloroplasts had a single
origin is correct, glaucophytes are closely related to both green plants and
red algae, and may be similar to the original alga type from which all of these
developed.

Glaucophytes have mitochondria with flat cristae, and undergo open mitosis
without centrioles. Motile forms have two unequal flagella, which may have
fine hairs and are anchored by a multilayered system of microtubules, both of
which are similar to forms found in some green algae.

The chloroplasts of
glaucophytes, like the cyanobacteria and the chloroplasts of red algae, use the
pigment phycobilin to capture some wavelengths of light; the green algae and
higher plants have lost that pigment.

There are three main genera included here. Glaucocystis is non-motile, though
it retains very short vestigial flagella, and has a cellulose wall. Cyanophora
is motile and lacks a cell wall. Gloeochaete has both motile and non-motile
stages, and has a cell wall that does not appear to be composed of cellulose.

DOMAIN Eukaryota - eukaryotes
KINGDOM Plantae Haeckel, 1866 - plants
SUBKINGDOM Biliphyta
Cavalier-Smith, 1981
PHYLUM Glaucophyta Skuja, 1954
CLASS Glaucocystophyceae
Schaffner, 1922


  
1,400,000,000 YBN
197) Opisthokonts (posterior cilium) evolve from Unikonts (ancestrally only one
cilium). Opisthokonts have flat mitochondrial cristae and go on to form the
Animal and Fungi kingdoms.

Thomas Cavalier-Smith and Ema E.-Y. Chao write: "The term
opisthokont, signifying "posterior cilium," was applied to animals, Choanozoa,
and Fungi because all three groups ancestrally had a single posterior cilium
(Cavalier-Smith 1987b). They were argued to be a clade because they also were
characterized (uniquely at the time) by flat, nondiscoid mitochondrial cristae
that were not irregularly inflated like the flat cristae of Plantae
(Cavalier-Smith 1987b). Four other characters also suggested that animals and
fungi were more closely related to each other than plants (chitinous
exoskeletons; storage of glycogen, not starch; absence of chloroplasts; and UGA
coding for tryptophane, not chain termination). However, the first three were
probably ancestral states for eukaryotes and the last convergent, so the
ciliary and cristal morphology were stronger indications. Although early rRNA
trees did not group animals and fungi together, the opisthokonts are now
consistently supported by all well-sampled rRNA trees and trees using several
or many proteins, as discussed above. Moreover a derived 12-amino acid
insertion in translation elongation factor 1agr and three small gaps in enolase
clearly indicate that animals and fungi have a common ancestor not shared with
plants (or other bikonts) or Amoebozoa (Baldauf and Palmer 1993; Baldauf 1999).
Thus opisthokonts are now well accepted as a robust clade of eukaryotes
(Patterson 1999)."



  
1,400,000,000 YBN
220) Amoebozoa (amoeba, slime molds) evolve now.
Ribosomal RNA shows the Protist
Phylum Amoebozoa (also called Ramicristates) which includes amoeba and slime
molds evolving now.

The Amoebozoa are a major group of amoeboid protozoa, including the majority
that move by means of internal cytoplasmic flow. Their pseudopodia are
characteristically blunt and finger-like, called lobopodia. Most are
unicellular, and are common in soils and aquatic habitats, with some found as
symbiotes of other organisms, including several pathogens. The Amoebozoa also
include the slime moulds, multinucleate or multicellular forms that produce
spores and are usually visible to the unaided eye.

Mycetozoa are the slime molds.
4. Plasmodial Slime Molds
a. Plasmodial
slime molds exist as a plasmodium. (the earlier evolved acrasid cellular slime
molds exist as individual amoeboid cells.)
b. This diploid multinucleated
cytoplasmic mass creeps along, phagocytizing decaying plant material.
c.
Fan-shaped plasmodium contains tubules of concentrated cytoplasm in which
liquefied cytoplasm streams.
d. Under unfavorable environmental conditions
(e.g., drought), the plasmodium develops many sporangia
that produce
spores by meiosis.
e. When mature, spores are released and survive until
more favorable environmental conditions return;
then each releases a
haploid flagellated cell or an amoeboid cell.
f. Two flagellated or
amoeboid cells fuse to form diploid zygote that produces a multi-nucleated
plasmodium.

Nuclear division in giant amoebas (Peolobiont/Amoebozoa) is neither mitosis nor
binary fission, but incorporates aspects of both (Fig. 3-7). Chromosomes are
attached permanently to the nuclear membrane by their centromeres (MTOCs,
microtubule organizing centers), and the nuclear membrane remains intact
throughout division. After DNA duplication produces two chromatids, the point
of attachment, the MTOC duplicates or divides, and microtubules are assembled
between the two resulting MTOCs. Elongating microtubules form something akin to
a spindle within the nuclear membrane that pushes the daughter chromosomes
apart and elongate the membrane-bounded nucleus until it blebs in half in
something akin to binary fission. Simple assembly of microtubules accomplishes
the separation of daughter genomes in this simple nuclear division. In typical
eukaryotic mitosis, the separation of daughter chromosomes is accomplished by a
dual action, the disassembly of spindle fibers connecting the daughter
chromosome to the polar MTOC, and assembly of spindle fibers running pole to
pole.

amoeba haplodiploid?

Thomas Cavalier-Smith and Ema E. -Y. Chao write: "Amoebozoa are a key
protozoan phylum because of the possibility that they are ancestrally
uniciliate and unicentriolar (Cavalier-Smith 2000a,b); present data on the
DHFR-TS gene fusion leaves open the possibility that they might be the
earliest-diverging eukaryotes (Stechmann and Cavalier-Smith 2002), but they may
be evolutionarily closer to bikonts or even opisthokonts. Amoebozoa comprise
two subphyla (Cavalier-Smith 1998a): Lobosa, classical aerobic amoebae with
broad ("lobose") pseudopods (including the testate Arcellinida), and Conosa
(slime molds {Mycetozoa, e.g., Dictyostelium} and amitochondrial-often
uniciliate-archamaebae {entamoebae, mastigamoebae}). Contrary to early analyses
(Sogin 1991; Cavalier-Smith 1993a), there is no reason to regard Amoebozoa as
polyphyletic; the defects of those classical uncorrected rRNA trees are shown
by trees using 123 proteins that robustly establish the monophyly of both
Archamoebae and Conosa (Bapteste et al. 2002). Unless the tree's root is within
Conosa, Dictyostelium and Entamoeba must have evolved independently from
aerobic flagellates by ciliary losses. A recent mitochondrial gene tree based
on concatenating six different proteins grouped Dictyostelium with Physarum
(99% support) and both Mycetozoa as sisters to Acanthamoeba (99% support), thus
providing strong evidence for the monophyly of Mycetozoa and the grouping of
Lobosa and Conosa as Amoebozoa (Forget et al. 2002)-the same tree also strongly
supports the idea based on morphology that Allomyces should be excluded from
Chytridiomycetes (in the separate class Allomycetes) and is phylogenetically
closer to zygomycetes and higher fungi (Cavalier-Smith 1998a, 2000c).
Furthermore, the derived gene fusion between two cytochrome oxidase genes, coxI
and coxII (Lang et al. 1999), strongly supports the holophyly of Mycetozoa.
Since Archamoebae secondarily lost mitochondria, the root cannot lie among them
either-although anaerobiosis in Archamoebae is derived, it is unjustified to
conclude from this that their simple ciliary root organization, which was a key
reason for considering them early eukaryotes (Cavalier-Smith 1991c), is also
secondarily derived (Edgcomb et al. 2002). Thus the root of the eukaryote tree
cannot lie within the Conosa.

As Mycetozoa and Archamoebae have very long-branch rRNA sequences, Conosa were
excluded from the analysis in Fig. 1, which includes only Lobosa. Although the
monophyly of Acanthamoebida (99%) and of Euamoebida (85%) is well supported,
the basal branching of the Lobosa is so poorly resolved that the monophyly of
Lobosa might appear open to question. The four lobosan lineages apparently
diverged early. However, in the 279- and 227-species trees, which included
Conosa, anaeromonads did not intrude into the Amoebozoa as they do in Fig. 1,
and Amoebozoa were monophyletic (low support) except for the exclusion of M.
invertens. M. invertens is another wandering branch, which in some taxon
sample/methods groups very weakly with other Amoebozoa, but more often ends up
in a different place in each tree! We concur with the judgment of Milyutina et
al. (2001)Edgcomb et al. (2002) that it should not be regarded as a pelobiont
or Archamoeba, but as a lobosan that independently became an anaerobe with
degenerate mitochondria. Its tendency to drift around the tree, coupled with
its short branch, suggests that it may be a particularly early-diverging
amoebozoan lineage. If so, its unicentriolar condition would give added support
to the idea that Amoebozoa are ancestrally uniciliate, if it could be shown
that Amoebozoa are either holophyletic or not at the base of the tree.

Most, if not all, amoebae evolved from amoeboid zooflagellates by multiple
ciliary losses (Cavalier-Smith 2000a). As the uniciliate condition is
widespread within Amoebozoa (Cavalier-Smith 2000a, 2002b), it may be their
ancestral condition; if so, ordinary nonciliate amoebozoan amoebae arose
several times independently. Evolution of amoebae from zooflagellates by
ciliary loss also occurred separately in Choanozoa to produce Nuclearia and in
several bikont groups, notably Percolozoa (heterolobosean amoebae, e.g.,
Vahlkampfia) and Cercozoa. However, we cannot currently exclude the possibility
that the eukaryote tree is rooted within the lobosan Amoebozoa, in which case
one of its nonciliate lineages (Euamoebida or Vanellidae) might be primitively
nonciliate and the earliest-diverging eukaryotic lineage. However, as the idea
that the nucleus and a single centriole and cilium coevolved in the ancestral
eukaryote (Cavalier-Smith 1987a) retains its theoretical merits, we think it
more likely that all Amoebozoa are derived from a uniciliate ancestor and that
crown Amoebozoa are a clade."

Amoebozoa vary greatly in size. Many are only 10-20 μm in size, but they
also include many of the larger protozoa. The famous species Amoeba proteus may
reach 800 μm in length, and partly on account of its size is often studied
as a representative cell. Multinucleate amoebae like Chaos and Pelomyxa may be
several millimetres in length, and some slime moulds cover several square feet.


The cell is typically divided into a granular central mass, called endoplasm,
and a clear outer layer, called ectoplasm. During locomotion the endoplasm
flows forwards and the ectoplasm runs backwards along the outside of the cell.
Many amoebae move with a definite anterior and posterior; in essence the cell
functions as a single pseudopod. They usually produce numerous clear
projections called subpseudopodia (or determinate pseudopodia), which have a
defined length and are not directly involved in locomotion.

Other amoebozoans may form multiple indeterminate pseudopodia, which are more
or less tubular and are mostly filled with granular endoplasm. The cell mass
flows into a leading pseudopod, and the others ultimately retract unless it
changes direction. Subpseudopodia are usually absent. In addition to a few
naked forms like Amoeba and Chaos, this includes most amoebae that produce
shells. These may be composed of organic materials, as in Arcella, or of
collected particles cemented together, as in Difflugia, with a single opening
through which the pseudopodia emerge.

The primary mode of nutrition is by phagocytosis: the cell surrounds potential
food particles, sealing them into vacuoles where the may be digested and
absorbed. Some amoebae have a posterior bulb called a uroid, which may serve to
accumulate waste, periodically detaching from the rest of the cell. When food
is scarce, most species can form cysts, which may be carried aerially and
introduce them to new environments. In slime moulds, these structures are
called spores, and form on stalked structures called fruiting bodies or
sporangia.

Most Amoebozoa lack flagella and more generally do not form
microtubule-supported structures except during mitosis. However, flagella occur
among the pelobionts, and many slime moulds produce biflagellate gametes. The
flagella is generally anchored by a cone of microtubules, suggesting a close
relationship to the opisthokonts. The mitochondria characteristically have
branching tubular cristae, but have been lost among pelobionts and the
parasitic entamoebids, collectively referred to as archamoebae based on the
earlier assumption that the absence was primitive.

Traditionally all amoebae with lobose pseudopods were treated together as the
Lobosea, placed with other amoeboids in the phylum Sarcodina or Rhizopoda, but
these were considered to be unnatural groups. Structural and genetic studies
identified several independent groups: the percolozoans, pelobionts, and
entamoebids. In phylogenies based on rRNA their representatives were separate
from other amoebae, and appeared to diverge near the base of eukaryotic
evolution, as did most slime molds.

However, revised trees by Cavalier-Smith and Chao in 1996 suggested that the
remaining lobosans do form a monophyletic group, and that the archamoebae and
Mycetozoa are closely related to it, although the percolozoans are not.
Subsequently they emended (to improve by editing) the older phylum Amoebozoa to
refer to this supergroup. Studies based on other genes have provided strong
support for the unity of this group. Patterson treated most with the testate
filose amoebae as the ramicristates, based on mitochondrial similarities, but
the latter are now removed to the Cercozoa.

Amoebae are difficult to classify, and relationships within the phylum remain
confused. Originally it was divided into the subphyla Conosa, comprising the
archamoebae and Mycetozoa, and Lobosa, including the more typical lobose
amoebae. Molecular phylogenies provide some support for this division if the
Lobosa are understood to be paraphyletic. They also suggest the morphological
families of naked lobosans may correspond at least partly to natural groups:

* Leptomyxida
* Amoebidae
* Hartmannellidae
* Paramoebidae
* Vannellidae
* Vexilliferidae
* Acanthamoebidae
* Stereomyxidae

However, many amoebae have not yet been studied via molecular techniques,
including all those that produce shells (Arcellinida).

PHYLUM Amoebozoa (Lühe, 1913 emend.) Cavalier-Smith, 1998
CLASS
Breviatea
CLASS Variosea
CLASS Phalansterea (T. Cavalier-Smith,
2000)
SUBPHYLUM Lobosa (Carpenter, 1861) Cavalier-Smith, 1997 (lobose
amoebas)
CLASS Amoebaea
CLASS Testacealobosea (includes shelled lobosid
amebas {testate amoebas})
CLASS Holomastigea T. Cavalier-Smith, 1997
("1996-1997")
SUBPHYLUM Conosa (Cavalier-Smith, 1998)
INTRAPHYLUM
Mycetozoa (De Bary, 1859) Cavalier-Smith, 1998 (Slime Molds)
SUPERCLASS Eumyxa
(Cavalier-Smith, 1993) Cavalier-Smith, 1998
CLASS Protostelea (C.J.
Alexopoulos & C.W. Mims, 1979 orthog. emend.)
CLASS Myxogastrea (E.M.
Fries, 1829 stat. nov. J. Feltgen, 1889 orthog. emend.) (plasmodial slime
molds)
SUPERCLASS Dictyostelia (Lister, 1909) Cavalier-Smith, 1998
CLASS
Dictyostelea™ (D.L. Hawksworth et al., 1983, orthog. emend.)
INTRAPHYLUM
Archamoebae (Cavalier-Smith, 1983) Cavalier-Smith, 1998
CLASS Pelobiontea
(F.C. Page, 1976 stat. nov. T. Cavalier-Smith, 1981)
CLASS Entamoebea
(T. Cavalier-Smith, 1991)

SUBPHYLUM Lobosa


SUBPHYLUM Conosa
The Conosea unifies amoebae which usually possess flagellate stages
or are amoeboflagellates. This clade consists of two relatively solid groups
� the Mycetozoa and Archamoebae, grouped by Cavalier-Smith (1998) in the
taxon Conosa, as well as a number of independent lineages, including two
flagellates � Phalansterium (Cavalier-Smith et al. 2004) and Multicilia
(Nikolaev et al. 2004), and two gymnamoebae � Gephyramoeba and Filamoeba
(Amaral Zettler et al. 2000). Because of large variations of the substitution
rates in SSU rRNA genes within this clade, its internal relationships are not
resolved yet.

The Mycetozoa comprises two distinct groups of �slime molds�
� the Myxogastria and Protostelia (Dykstra and Keller 2000). This is a
well-defined group of protists, characterized by the ability to form so-called
�fruiting bodies�. In some lineages of Mycetozoa the fruiting
body is raised over the substratum on a distinct stalk. Both groups possess
complex life cycles including an aggregation of cells, however the essential
difference between them is that in Protostelia, only a pseudoplasmodium is
formed (without fusion of the cells constituting the aggregate), while in
Myxogastria a true plasmodium is formed (the cells completely fuse, forming a
single organism) (Olive 1975; Dykstra and Keller 2000). The monophyly of
Mycetozoa was proposed based on elongation factor 1-alpha gene sequences
(Baldauf and Doolittle 1997) but it is not always recovered in SSU rRNA trees
(Cavalier-Smith et al. 2004; Nikolaev et al. 2004).

The Archamoebae comprise amoeboid and amoeboflagellate protists characterized
by a secondary absence of mitochondria (mostly due to parasitism or life in
anoxic environments). This group includes the free-living genera Mastigamoeba,
Mastigella, and Pelomyxa (the pelobionts) and the parasitic genera Entamoeba
and Endolimax (the entamoebids). The consistent grouping of all these
amitochondriate amoeboid organisms in both SSU rRNA and actin gene phylogenies
(Fahrni et al. 2003) suggests a single loss of the mitochondria during the
evolution of Amoebozoa.

CLASS Amoebaea
ORDER Euamoebida Lepsi, 1960
FAMILY Amoebidae (Ehrenberg 1838)
The
Amoebidae are a family of amoebozoa, including naked amoebae that produce
multiple pseudopodia of indeterminate length. These are roughly cylindrical in
form, with a central stream of granular endoplasm, and do not have
subpseudopodia. During locomotion one pseudopod typically becomes dominant, and
the others are retracted as the body flows into it. In some cases the cell
moves by "walking", with the relatively permanent pseudopodia serving as limbs.


The most important genera are Amoeba and Chaos, which are set apart from the
others by longitudinal ridges. They group together on molecular trees,
suggesting the Amoebidae are a natural group. Shelled amoebozoans have not been
studied molecularly but produce very similar pseudopodia, so although they are
traditionally classified separately they may be closely related to this group.


GENUS Amoeba (Bery de St. Vincent 1822)
Amoeba (also spelled ameba) is a genus
of protozoa that moves by means of temporary projections called pseudopods, and
is well-known as a representative unicellular organism. The word amoeba is
variously used to refer to it and its close relatives, now grouped as the
Amoebozoa, or to all protozoa that move using pseudopods, otherwise termed
amoeboids.

Amoeba itself is found in freshwater, typically on decaying vegetation from
streams, but is not especially common in nature. However, because of the ease
with which they may be obtained and kept in the lab, they are common objects of
study, both as representative protozoa and to demonstrate cell structure and
function. The cells have several lobose pseudopods, with one large tubular
pseudopod at the anterior and several secondary ones branching to the sides.
The most famous species, Amoeba proteus, is 700-800 μm in length, but many
others are much smaller. Each has a single nucleus, and a simple contractile
vacuole which maintains its osmotic pressure, as its most recognizable
features.

Early naturalists referred to Amoeba as the Proteus animalcule, after a Greek
god who could change his shape. The name "amibe" was given to it by Bery St.
Vincent, from the Greek amoibe, meaning change.

A good method of collecting amoeba is to lower a jar upside down until it is
just above the sediment surface. Then one should slowly let the air escape so
the top layer will be sucked into the jar. Deeper sediment should not be
allowed to get sucked in. It is possible to slowly move the jar when tilting it
to collect from a larger area. If no amoeba are found, one can try introducing
some rice grains into the jar and waiting for them to start to rot. The
bacteria eating the rice will be eaten by the amoeba, thus increasing the
population and making them easier to find.

Family Hartmannellidae (Volkonsky 1931)
The Hartmannellidae are a common family of
amoebozoa, usually found in soils. When active they tend to be roughly
cylindrical in shape, with a single leading pseudopod and no subpseudopodia.
This form somewhat resembles a slug, and as such they are also called limax
amoebae. Trees based on rRNA show the Hartmannellidae are paraphyletic to the
Amoebidae and Leptomyxida, which may adopt similar forms.

FAMILY Vannellidae (Bovee 1970)
The Vannellidae are a distinctive family of
amoebozoa. During locomotion they tend to be flattened and fan-shaped, although
some are long and narrow, and have a prominent clear margin at the anterior. In
most amoebae, the endoplasm glides forwards through the center of the cell, but
in vannellids the cell undergoes a sort of rolling motion, with the outer
membrane sliding around like a tank tread.

These amoebae are usually 10-40 μm in size, but some are smaller or
larger. The most common genus is Vannella, found mainly in soils, but also in
freshwater and marine habitats. Trees based on rRNA support the monophyly of
the family.

SUBPHYLUM Conosa Cavalier-Smith, 1998
INTRAPHYLUM Archamoebae (Cavalier-Smith,
1983) Cavalier-Smith, 1998
CLASS Pelobiontea F.C. Page, 1976 stat. nov. T.
Cavalier-Smith, 1981
ORDER Pelobiontida (Page 1976)
The pelobionts are a small group
of amoebozoa. The most notable member is Pelomyxa, a giant amoeba with multiple
nuclei and inconspicuous non-motile flagella. The other genera, called
mastigamoebae, are often uninucleate, have a single anterior flagellum used in
swimming, and produce numerous determinate pseudopodia.

Pelobionts are closely related to the entamoebids and like them have no
mitochondria; in addition, pelobionts also do not have dictyosomes. At one
point these absences were considered primitive. However, molecular trees place
the two groups with other lobose amoebae in the phylum Amoebozoa, so these are
secondary losses.

SUBPHYLUM Conosa Cavalier-Smith, 1998
INTRAPHYLUM Archamoebae (Cavalier-Smith,
1983) Cavalier-Smith, 1998
CLASS Entamoebea T. Cavalier-Smith, 1991
The entamoebids
or entamoebae are a group of amoebozoa found as internal parasites or
commensals of animals. The cells are uninucleate small, typically 10-100
μm across, and usually have a single lobose pseudopod taking the form of a
clear anterior bulge. There are two major genera, Entamoeba and Endolimax. They
include several species that are pathogenic in humans, most notably Entamoeba
histolytica, which causes amoebic dysentery.

Entamoebids lack mitochondria. This is a secondary loss, possibly associated
with their parasitic life-cycle. Studies show they are close relatives of the
pelobionts, another group of amitochondriate amoebae, but unlike them
entamoebids retain dictyosomes. Both groups are now placed alongside other
lobose amoebae in the phylum Amoebozoa.

Studying Entamoeba invadens, David Biron of the Weizmann Institute of Science
and coworkers found that about one third of the cells are unable to separate
unaided and recruit a neighboring amoeba (dubbed the "midwife") to complete the
fission. He writes:

"When an amoeba divides, the two daughter cells stay attached by a tubular
tether which remains intact unless mechanically severed. If called upon, the
neighbouring amoeba midwife travels up to 200 μm towards the dividing
amoeba, usually advancing in a straight trajectory with an average velocity of
about 0.5 μm/s. The midwife then proceeds to rupture the connection, after
which all three amoebae move on."

They also reported a similar behavior in Dictyostelium.

Entamoeba coli is a non-pathogenic species of entamoebid that is important
clinically in humans only because it can be confused with Entamoeba
histolytica, which is pathogenic, on microscopic examination of stained stool
specimens. A simple finding of Entamoeba coli trophozoites or cysts in a stool
specimen requires no treatment.

Entamoeba histolytica is an anaerobic parasitic protozoan, classified as an
entamoebid. It infects predominantly humans and other primates. Diverse mammals
such as dogs and cats can become infected but usually do not shed cysts (the
environmental survival form of the organism) with their feces, thus do not
contribute significantly to transmission. The active (trophozoite) stage exists
only in the host and in fresh feces; cysts survive outside the host in water
and soils and on foods, especially under moist conditions on the latter. When
swallowed they cause infections by excysting (to the trophozoite stage) in the
digestive tract.

Endolimax nana, a small entamoebid that is a commensal of the human intestine,
causes no known disease. It is most significant in medicine because it can
provide false positives for other tests, such as for the related species
Entamoeba histolytica which causes amoebic dysentery, and because its presence
indicates that the host once consumed feces. It forms cysts with four nuclei
which excyst in the body and become trophozoites. Endolimax nana nuclei have a
large endosome somewhat off-center and small amounts of visible chromatin or
none at all.

Actinopod reproduction may involve binary fission or the formation of swarmer
cells, and sexual processes occur in some groups. Their mitochondrial cristae
are usually tubular, but in some groups there are vesicular or flattened,
plate-like cristae.


  
1,300,000,000 YBN
188) Green Algae, composed of the 2 Phlya Chlorophyta (volvox, sea lettuce) and
Charophyta (Spirogyra) evolve.

Genetic comparison shows Green Algae, composed
of the 2 Phlya Chlorophyta (volvox, sea lettuce) and Charophyta (Spirogyra)
evolving now.

The Green Algae are the large group of algae from which the embryophytes
(higher plants) emerged. As such they form a paraphyletic group, some people
placing them in the Plantae Kingdom, while others placing them in the Protist
Kingdom.

Almost all forms have chloroplasts. They are bound by a double membrane, so
presumably were acquired by direct endosymbiosis of cyanobacteria.

All green algae have mitochondria with flat cristae. When present flagella are
typically anchored by a cross-shaped system of microtubules, but these are
absent among the higher plants and charophytes. They usually have cell walls
containing cellulose, and undergo open mitosis without centrioles. Sexual
reproduction varies from fusion of identical cells (isogamy) to fertilization
of a large non-motile cell by a smaller motile one (oogamy). However, these
traits show some variation, most notably among the basal green algae, called
prasinophytes.

The first land plants most likely evolved from green algae.

Here is where the green algae separate from the ancestor of the first land
plants.

Spirogyra reproduce through conjugation, which either was inherited from
prokaryotes or evolved a second time in eukaryotes.

Some filamentous green algae (e.g. cladophora) are haplodiploid (alternate
between haploid and diploid cycles that both have mitosis).

1. Phylum Chlorophyta (green
algae) contains about 7,000 species.
2. Most live in the ocean but are more
likely found in fresh water; they can even be found on moist land.
3. Green
algae are believed to be closely related to the first plants because both of
these groups
a. have a cell wall that contains cellulose,
b. possess
chlorophylls a and b, and
c. store reserve food as starch inside of the
chloroplast.
4. Green algae are not always green; some have pigments that give them
an orange, red, or rust color.
5. Body organizations include single cells,
colonies, filaments and multicellular forms.

C. Flagellated Green Algae
1. Chlamydomonas is a unicellular green alga less
than 25 cm long. (Fig. 30.3)
2. It has a cell wall and a single, large,
cup-shaped chloroplast with a pyrenoid for starch synthesis.
3. The chloroplast
contains a light-sensitive eyespot (stigma) that directs the cell to light for
photosynthesis.
4. Two long whip-like flagella project from the anterior end to propel
the cell toward light.
5. When growth conditions are favorable, Chlamydomonas
reproduces asexually with zoospores.
6. When growth conditions are unfavorable,
Chlamydomonas reproduces sexually.
a. Gametes from two different mating types
join to form a zygote.
b. A heavy wall forms around the zygote; a resistant
zygospores survives until conditions are favorable.
c. Some are heterogametes
similar to sperm and egg that stores food, a condition called oogamy.
d. In
most, gametes are identical, a condition called isogamy.

D. Filamentous Green Algae
1. Cell division in one plane produces
end-to-end chains of cells or filaments.
2. Spirogyra is a filamentous algae found
on surfaces of ponds and streams.
a. It has ribbon-like spiral chloroplasts.
(Fig. 30.4)
b. Two strands may unite in conjugation and exchange genetic
material, forming a diploid zygote.
c. The zygotes withstand winter; in
spring they undergo meiosis to produce haploid filaments.
3. Oedogonium is another
filamentous algae.
a. It has cylindrical cells with netlike chloroplasts.
b.
During sexual reproduction, there is a definite egg and sperm.

E. Multicellular Green Algae
1. Multicellular Ulva is called sea lettuce
because of its leafy appearance. (Fig. 30.5)
2. The thallus (body) is two
cells thick but can be a meter long.
3. Ulva has an alternation of
generations life cycle, as do plants, but the generations look alike.
4. The
gametes look alike (isogametes) and the spores are flagellated.
5. In true plants,
one generation is dominant, sperm and eggs are produced, and spores lack
flagella.

F. Colonial Green Algae
1. Volvox is a hollow sphere with thousands of
cells arranged in a single layer. (Fig. 30.6)
2. Volvox cells resembles
Chlamydomonas cells; a colony arises as if daughter cells fail to separate.
3.
Volvox cells cooperate when flagella beat in a coordinated fashion.
4. Some
cells are specialized forming a new daughter colony within the parental
colony.
5. Daughter colonies are inside a parent colony until an enzyme
dissolves part of a wall so it can escape.
6. Sexual reproduction involves
oogamy

Order Chlorococcales, probably includes the first coccoidal green algae,
probably even the earliest eukaryotes, but unequivocal indentification in the
Precambrien is unlikely to be achived.

Spirogyra reproduce through conjugation, which either was inherited from
prokaryotes or evolved a second time in eukaryotes. If inherited from
prokaryotes, then spirogrya would be very old although the fossil record and
Ribosomal RNA put them late compared to other algae.


  
1,300,000,000 YBN
209) Red Algae (Rhodophyta) evolve now.
Genetic comparison show Phylum Rhodophyta
(red algae) evolves now.

There are between 2500 and 6000 species in about 670 largely marine genera.

Many red algae are haplodiploid (alternate between haploid and diploid cycles
that both have mitosis).

The red algae (Rhodophyta) are a large group of mostly multicellular, marine
algae, including many notable seaweeds. Most of the coralline algae, which
secrete calcium carbonate and play a major role in building coral reefs, belong
here. Red algae such as dulse and nori are a traditional part of European and
Asian cuisine and are used to make certain other products like agar and food
additives.

Many red algae have multicellular stages but these lack differentiated tissues
and organs. Unlike most other algae, no cells with a flagellum are found in any
member of the group. Unicellular forms typically live attached to surfaces
rather than floating among the plankton, and both the larger female and smaller
male gametes are non-motile, so that most have a low chance of fertilization.
They have cell walls are made out of cellulose and thick gelatinous
polysaccharides, which are the basis for most of the industrial products made
from red algae.

The chloroplasts of red algae are bound by a double membrane, like those of
green plants; both groups (Archaeplastida) probably share a common origin.
Their plastids formed by direct endosymbiosis of a cyanobacteria, and in red
algae are pigmented with chlorophyll a and various proteins called phycobilins,
which are responsible for their reddish color. Other algae that lack
chlorophyll b appear to have acquired their chloroplasts from red algae,
although their pigmentations are somewhat different.

unicellular to multicellular (up to 1 m) mostly free-living but some parasitic
or symbiotic, with chloroplasts containing phycobilins. Cell walls made of
cellulose with mucopolysaccharides penetrated in many red algae by pores
partially blocked by proteins (complex referred to as pit connections). Usually
with separated phases of vegetative growth and sexual reproduction. Common and
widespread, ecologically important, economically important (source of agar). No
flagella. Ultrastructural identity: Mitochondria with flat cristae, sometimes
associated with forming faces of dictyosomes. Thylakoids single, with
phycobilisomes, plastids with peripheral thylakoid. During mitosis, nuclear
envelope mostly remains intact but some microtubules of spindle extend from
noncentriolar polar bodies through polar gaps in the nuclear envelope.
Synapomorphy: No clear-cut feature available; possibly pit connections
Composition: About 4,000 species.

CLASS Florideophyceae
CLASS Bangiophyceae
CLASS Rhodellophyceae

DOMAIN Eukaryota - eukaryotes
KINGDOM Plantae Haeckel, 1866 - plants

SUBKINGDOM Biliphyta Cavalier-Smith, 1981
PHYLUM Rhodophyta Wettstein, 1922 -
red algae
SUBPHYLUM Rhodellophytina Cavalier-Smith, 1998
CLASS
Rhodellophyceae™ Cavalier-Smith, 1998
SUBPHYLUM Macrorhodophytina
Cavalier-Smith, 1998
CLASS Bangiophyceae
CLASS Florideophyceae

There is a debate as to if Rhodophyta are plants or protists.

1. Red algae (phylum Rhodophyta) are chiefly marine multicellular algae
that live in warmer seawater.
2. They are generally much smaller and more
delicate that brown algae.
3. Some are filamentous, but most are branched,
having a feathery, flat, or ribbon-like appearance. (Fig. 30.7)
4. Coralline
algae are red algae with cell walls with calcium carbonate; they contribute to
coral reefs.
5. Sexual reproduction involves oogamy but the sperm are
non-flagellated.
6. Their chloroplasts resemble cyanobacteria by containing chlorophyll
a and the pigment phycobilin.
7. The food reserve (floridean starch) resembles
glycogen.
8. Like brown algae, red algae are economically important.
a.
Mucilaginous material in cell walls is source of agar used in drug capsules,
dental impressions, cosmetics.
b. In the laboratory, agar is a major
microbiological media, and when purified, is a gel for electrophoresis.
c. Agar is
used in food preparation to keep baked goods from drying and to set jellies and
desserts.


The taxonomy of the algae is still in a state of flux.


  
1,280,000,000 YBN
187) A eukaryote rhodophyte (red alga) is enslaved by a chromealveolate
eukaryote to form a plastid in the chromealveolate. This kind of plastid is
presumably inherited by all other chromalveolates (brown algae, diatoms, water
molds, Dinoflagellata, Apicomplexa, ciliates) that have plastids.

If this red alga
endosymbiosis occured only once, then all chromalveolates with plastids
inherited them and all without lost them. Ciliates presumably lost any
inherited plastids.



  
1,250,000,000 YBN
201) Oldest widely accepted Rhodophyta (red algae) fossils (Bangiomorpha
pubescens) from Hunting Formation, Somerset Island, arctic Canada.

This is the
oldest multicellular eukaryote fossil and the oldest fossil of a sexual species
found yet.



  
1,230,000,000 YBN
153) Amino acid sequence comparison shows the protist and plant line separating
here at 1,230 mybn (first plant).


  
1,100,000,000 YBN
75) Most ancient living fungi phylum "Microsporidia" evolves.
Ribosomal RNA shows most
ancient living fungi phylum "Microsporidia" evolving now.

Microsporidia are parasites of animals, now considered to be extremely reduced
fungi. Most infect insects, but they are also responsible for common diseases
of crustaceans and fish, and have been found in most other animal groups,
including humans and other mammals which can be parasitized by species of
Encephalitozoon. Replication takes place within the host's cells, which are
infected by means of unicellular spores. These vary from 1-40 μm, making
them some of the smallest eukaryotes. They also have the shortest eukaryotic
genomes.

Microsporidia are unusual in lacking mitochondria, and also lack motile
structures such as flagella. The spores are protected by a layered wall
including proteins and chitin. Their interior is dominated by a unique coiled
structure called a polar tube (not to be confused with the polar filaments of
Myxozoa). In most cases there are two closely associated nuclei, forming a
diplokaryon, but sometimes there is only one.

Intracellular parasites, no mitochondria, ribosomes are unusual in being of
prokaryotic size (70S) and lacking characteristic eukaryotic 5.8S ribosomal
RNA as a separate molecule in the microsporidia but is incorporated into the
23S r RNA.

binucleate haploid?

During infection, the polar tube penetrates the host cell (the
process has been compared by Patrick J. Keeling to "turning a garden hose
inside out"), and the contents of the spore are pumped through it. Keeling
likens the system to a combination of "harpoon and hypodermic syringe", adding
that it is "one of the most sophisticated infection mechanisms in biology".

Once inside the host cell, the sporoplasm grows, dividing or forming a
multinucleate plasmodium before producing new spores. The plasmodium
divides by merogony to produce merozoites that enter other host cells, to
repeat merogony, or to undergo sporogony. The latter parasites divide by
binary fission to produce numerous sporoblasts which develop into spores.

The life cycle varies considerably. Some have a simple asexual life cycle,
while others have a complex life cycle involving multiple hosts and both
asexual and sexual reproduction. Different types of spores may be produced at
different stages, probably with different functions including autoinfection
(transmission within a single host). The Microsporidia often cause chronic,
debilitating diseases rather than lethal infections. Effects on the host
include reduced longevity, fertility, weight, and general vigor. Vertical
transmission of microsporidia is frequently reported.

Because they are unicellular, Microsporidia were traditionally treated as
protozoa, and like other amitochondriate eukaryotes were considered to have
diverged very early on. However, other genes place them alongside or within the
Fungi, and this is supported by several chemical and morphological features. In
particular they appear to be allied with the Zygomycota or Ascomycota.

Comparison of tubulin gene sequences suggest that they are related to fungi;
hosts include most invertebrate phyla; all classes of vertebrates, the greatest
number of species being known from arthropods and fish; with growing and
dividing stages (meronts and sporonts), and spores which are used for
transmission between hosts; meronts with one nucleus or two closely adhering
and synchronously dividing nuclei; with endoplasmic reticulum, ribosomes and an
atypical dictyosome but no mitochondria, flagella, or cytoskeletal structures;
sporonts have more abundant endoplasmic reticulum and develop a surface coat
which becomes the outer layer of the spore wall; spores unicellular with one or
two nuclei, a polar tube (polar filament), the polaroplast and the posterior
vacuole; cytoplasm and nucleus (or nuclei) become the infective agent
(sporoplasm), as it emerges from the spore; meronts, ranging from small rounded
cells to plasmodia or ribbon-like formations, divide repeatedly by binary
fission, plasmotomy or multiple fission; merogony is followed by sporogony, in
which cells known as sporonts are committed to spore production; sporonts,
divide into sporoblasts, the number of which is characteristic of the genera;
sporoblasts mature into spores; but individual life cycles are highly variable;
meiosis occurs and this indicates that gametogenesis and fusion of gametes must
occur but this has been recognised for only a few species; genera with an
alternation of diplokaryotic and monokaryotic stages can be dimorphic and
heterosporous. Genus descriptions are usually based on the type species.

DOMAIN Eukaryota - eukaryotes
KINGDOM Fungi (Linnaeus, 1753) Nees, 1817 - fungi
PHYLUM
Microsporidia (Balbiani, 1882) Weiser, 1977


  
1,000,000,000 YBN
154) Amino acid sequence comparison shows the plant and fungi line separating
here at 1,000 mybn (first fungi).


  
1,000,000,000 YBN
223) Fungi phylum "Chytridiomycota" evolves.
Ribosomal RNA place fungi phylum
"Chytridiomycota" evolving now.

Many chytrids are haplodiploid (alternate between haploid and diploid cycles
that both have mitosis).

Chytridiomycota is a division of the Fungi kingdom and contains only one class,
Chytridiomycetes. The name refers to the chytridium (from the Greek,
chytridion, meaning "little pot"): the structure containing unreleased spores.

The chytrids are the most primitive of the fungi and are mostly saprobic (feed
on dead species, degrading chitin and keratin). Many chytrids are aquatic
(mostly found in freshwater). There are approximately 1,000 chytrid species, in
127 genera, distributed among 5 orders. Both zoospores and gametes of the
chytrids are mobile by their flagella, one whiplash per individual. The thalli
are coenocytic and usually form no true mycelium (having rhizoids instead).
Some species are unicellular.

DOMAIN Eukaryota - eukaryotes
KINGDOM Fungi (Linnaeus,
1753) Nees, 1817 - fungi
PHYLUM Chytridiomycota
CLASS Chytridiomycetes™ (De Bary, 1863)
Sparrow, 1958

Some chytrid species are known to kill frogs in large numbers by blocking the
frogs' respiratory skins - the infection is referred to as chytridomycosis.
Decline in frog populations led to the discovery of chytridomycosis in 1998 in
Australia and Panama. Chytrids may also infect plant species; in particular,
maize-attacking and alfalfa-attacking species have been described.


  
1,000,000,000 YBN
324) Phylum Choanozoa (Mesomycetozoea/DRIPs, Choanoflagellates) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa (Goldfuss, 1818) R. Owen, 1858 -
protozoa
SUBKINGDOM Sarcomastigota (means=?)
PHYLUM Amoebozoa (Lühe, 1913)
Cavalier-Smith, 1998
PHYLUM Choanozoa
CLASS Choanoflagellatea
(Choanoflagellates)
CLASS Corallochytrea
CLASS Mesomycetozoea Mendoza et al., 2001 (DRIPs)
CLASS
Cristidiscoidea


  
1,000,000,000 YBN
325) The Choanozoan "Mesomycetozoaea" (DRIPs) evolve.
The Mesomycetozoea or
DRIP clade are a small group of protists, mostly parasites of fish and other
animals. One species, Rhinosporidium seeberi, infects birds and mammals,
including humans. They are not particularly distinctive morphologically,
appearing in host tissues as enlarged spheres or ovals containing spores, and
most were originally classified in various groups of fungi, protozoa, and
algae. However, they form a coherent group on molecular trees, closely related
to both animals and fungi and so of interest to biologists studying their
origins.

The name DRIP is an acronym for the first protozoa identified as members of the
group - Dermocystidium, the rosette agent, Ichthyophonus, and Psorospermium.
Cavalier-Smith later treated them as the class Ichthyosporea, since they were
all parasites of fish. Since other new members have been added, Mendoza et al.
suggested changing the name to Mesomycetozoea, which refers to their
evolutionary position. Note the name Mesomycetozoa (without a second e) is also
used to refer to this group, but Mendoza et al. use it as an alternate name for
the phylum Choanozoa.

Assemblage identified from molecular studies, mostly pathogens, a few genera,
no synapomorphy. Grouping formalized by Herr, Ajello, Taylor, Arseculeratne &
Mendoza, 1999.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa (Goldfuss, 1818) R. Owen,
1858 - protozoa
SUBKINGDOM Sarcomastigota (means=?)
PHYLUM Amoebozoa (Lühe, 1913)
Cavalier-Smith, 1998
PHYLUM Choanozoa
CLASS Choanoflagellatea
(Choanoflagellates)
CLASS Corallochytrea
CLASS Mesomycetozoea Mendoza et al., 2001 (DRIPs)
CLASS
Cristidiscoidea



  
1,000,000,000 YBN
585) The Neoproterozoic (1.0-0.65Ga) is a period of dramatic global change and
quickening reef evolution. The appearance of heavily calcified microbial
elements (calcimicrobes; e.g. Girvanella and Renalcis) in the Tonian
(1.0-0.85Ga), coincident with the disappearance of conical elements and decline
in stromatolites, is a critical event.





  
967,000,000 YBN
97) A lens and light sensitive area evolve in unicellular eukaryote living
objects. This is the first proto eye.

The eye spot probably evolved from a
plastid, and plastids may have only formed symbiotic relationships in
euglenozoa much later, since the plastids in euglenozoa are enclosed in 3
membranes (the same as chloroplasts in plants), they are thought to have been
formed from captured green algae which evolve much later.



  
965,000,000 YBN
155) Amino acid sequence comparison shows the fungi and pseudocoeles lines
separating here at 965 mybn (first pseudocoel and first animal).


  
900,000,000 YBN
326) The Choanozoans "Choanoflagellates" and "Acanthoecida" evolve.
The
choanoflagellates are a group of flagellate protozoa. They are considered to be
the closest relatives of the animals, and in particular may be the direct
ancestors of sponges.

Each choanoflagellate has a single flagellum, surrounded by a ring of hairlike
protrusions called microvilli, forming a cylindrical or conical collar (choanos
in Greek). The flagellum pulls water through the collar, and small food
particles are captured by the microvilli and ingested. It also pushes
free-swimming cells along, as in animal sperm, whereas most other flagellates
are pulled by their flagella.

Most choanoflagellates are sessile, with a stalk opposite the flagellum. A
number of species are colonial, usually taking the form of a cluster of cells
on a single stalk. Of special note is Proterospongia, which takes the form of a
glob of cells, of which the external cells are typical flagellates with
collars, but the internal cells are non-motile.

The choanocytes (also known as "collared cells") of sponges have the same basic
structure as choanoflagellates. Collared cells are occasionally found in a few
other animal groups, such as flatworms. These relationships make colonial
choanoflagellates a plausible candidate as the ancestors of the animal kingdom.

DOMAIN Eukaryota - eukaryotes
KINGDOM Protozoa (Goldfuss, 1818) R. Owen, 1858 -
protozoa
SUBKINGDOM Sarcomastigota (means=?)
PHYLUM Amoebozoa (Lühe, 1913)
Cavalier-Smith, 1998
PHYLUM Choanozoa
CLASS Choanoflagellatea (Choanoflagellates
and Acanthoecida)
ORDER Choanoflagellida™ W.S. Kent, 1880 - (Choanoflagellates)
ORDER
Acanthoecida
CLASS Corallochytrea
CLASS Mesomycetozoea Mendoza et al., 2001 (DRIPs)
CLASS
Cristidiscoidea

Also identified in the Phylum Choanozoa are the Ichthyosporea.


  
855,000,000 YBN
286) A key step in metazoan multicellularity evolves, where a zygote produces
differentiated cells that stick together to form one organism.

Metazoan multicellularity
appears to be different from colonialism (where independent cells of the same
species work together and function as one unit), because one zygote produces
all the cells in the organism.



  
850,000,000 YBN
81) First animal and first metazoan evolve. Metazoans are multicellular, but
their cells perform different functions and originate from one cell(?). This
is`also the beginning of the Animal Subkingdom "Radiata", species with radial
symmetry. These are the sponges. There are only 3 kinds of metazoans: sponges,
cnidarians, and bilaterians (which include all insects and vertibrates).
Sponges are the first organisms whose DNA codes for more than one kind of cell.
Sponges have 3 different cell types. Some cells form a body wall, some digest
food, some form a skeletal frame.

All sponge cells are totipotent and are capable of
regrowing a new sponge.
The two major subkingdoms of the Kingdom Animalia are
Radiata (the radiates) and Bilateria (the bilaterians).



  
850,000,000 YBN
101) First homeobox, or "hox" genes evolve. These genes regulate the building
of major body parts.




  
850,000,000 YBN
224) Genetic comparison shows Fungi division "Zygomycota" (bread molds, pin
molds, microsporidia,...) evolving now.




  
780,000,000 YBN
79) Animal Phylum "Placozoa" evolves.
Placozoans look like amoebas but are
multicellular.

There is only one known species, "Tricoplax adhaerens", and one other potential
species "Tricoplax reptans" in the entire Placozoa phylum.

Putative eggs have been observed, but they degrade at the 32-64 cell stage.
Neither embryonic development nor sperm have been observed, however Trichoplax
genomes show evidence of sexual reproduction. Asexual reproduction by binary
fission is the primary mode of reproduction observed in the lab.

The haploid number of chromosomes is six. It has the smallest amount of DNA yet
measured for any animal with only 50 megabases (80 femtograms per cell). A
trichoplax genome project is currently underway.

DOMAIN Eukaryota -
eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Radiata (Linnaeus, 1758)
Cavalier-Smith, 1983 - radiates
INFRAKINGDOM Placozoa Cavalier-Smith, 1998

PHYLUM Placozoa™ Grell, 1971


  
750,000,000 YBN
83) Animal Phlyum Ctenophora (comb jellies) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Radiata
(Linnaeus, 1758) Cavalier-Smith, 1983 - radiates
INFRAKINGDOM Coelenterata
Leuckart, 1847
PHYLUM Ctenophora Eschscholtz, 1829 - comb jellies
CLASS
Tentaculata
CLASS Nuda


  
750,000,000 YBN
225) Genetic comparison shows Fungi division "Glomeromycota" (Arbuscular
mycorrhizal fungi) evolving now.




  
700,000,000 YBN
82) First cnidarians (coelantrates), jellyfish evolves. Jellyfish have photon
detecting cells and a lens made of ?.




  
700,000,000 YBN
226) The second largest group of Fungi, the phylum "Basidiomycota" (most
mushrooms, rusts, club fungi) evolve.

Genetic comparison shows the second largest
group of Fungi, the phylum "Basidiomycota" (most mushrooms, rusts, club fungi)
evolving now.

The Division Basidiomycota is a large taxon within the Kingdom Fungi that
includes those species that produce spores in a club-shaped structure called a
basidium. Essentially the sibling group of the Ascomycota, it contains some
30,000 species (37% of the described fungi)



  
700,000,000 YBN
227) The largest Fungi phylum "Ascomycota" (yeasts, truffles, Penicillium,
morels, sac fungi) evolves.

Genetic comparison shows the largest Fungi phylum
"Ascomycota" (yeasts, truffles, Penicillium, morels, sac fungi) evolving now.
47,000
described species.



  
700,000,000 YBN
228) Genetic comparison shows the largest and second largest lines of Fungi
(Ascomycota and Basidiomycota) splitting now.




  
680,000,000 YBN
222) Genetic comparison shows the Class of Ascomycota Fungi called
"Archaeascomycetes" (fission yeast, pneumonia fungus) evolving now.



  
675,000,000 YBN
156) Amino acid sequence comparison shows the pseudocoel and schizocoel lines
separating here at 675 mybn (first schizocoel).


  
650,000,000 YBN
69) Start of Varanger Ice Age (650-590 mybn).


  
650,000,000 YBN
229) Genetic comparison shows the Ascomycota Fungi "Hemiascomycetes" evolving
now.



  
630,000,000 YBN
91) First bilateral (has 2 sided symmetry) species evolves. Animal phylum
Acoelomorpha (acoela flat worms and nemertodermatida) evolves.
This begins the
Subkingdom "Bilateria".

lack a digestive track, anus and coelom.
DOMAIN
Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria
(Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
PHYLUM "Acoelomorpha" -
acoelomorphs
ORDER Acoela - acoels
ORDER Nemertodermatida - nemertodermatids


  
600,000,000 YBN
231) Basidiomycota Fungi "Ustilaginomycetes" (corn smut fungus) and
"Hymenomycetes" (white rot fungus) evolve.

Genetic comparison shows the Basidiomycota
Fungi "Ustilaginomycetes" (corn smut fungus) and "Hymenomycetes" (white rot
fungus) evolving now.


  
590,000,000 YBN
70) End of Varanger Ice Age (650-590 mybn).


  
590,000,000 YBN
93) Protostomes evolve. Many phyla evolve at this time. Protostomes include
the 3 infrakingdoms Ecdysozoa (a variety of worms and the arthropods {a huge
group including all insects and crustaceans}), Platyzoa (rotifers and
flatworms), and Lophotrochozoa (brachiopods {clams}, molluscs {snails}, and a
variety of worms).




  
580,000,000 YBN
94) Earliest animal fossil from Doushantuo formation in China.



  
580,000,000 YBN
165) Earliest bilaterian fossil, Vernanimalcula, 178 um in length, from
Doushantuo Formation, China. First fossil of organism with bilateral symmetry,
mouth, digestive track, gut and anus.




  
580,000,000 YBN
318) Protostome Infrakingdom Ecdysozoa evolves. Ecdysozoa are animals that
molt (lose their outer skins) as they grow.
Ecdysozoa include:
the Phylum "Chaetognatha"
(Arrow Worms),
the Superphylum "Aschelminthes", containing the 5 Phlya:

"Kinorhyncha" (kinorhynchs)
"Loricifera" (loriciferans)
"Nematoda" (round worms)
"Nematomorpha" (horsehair
worms),
"Priapulida" (priapulids)
the Superphlyum "Panarthropoda" containing the 3 Phyla:
"Arthropoda"
(arthropods: insects, shell fish)
"Onychophora" (onychophorans)
"Tardigrada" (tardigrades)




  
578,000,000 YBN
92) First nematocyst (stinging cells) evolve on Jellyfish(?).

  
575,000,000 YBN
107) Start of fossils in Ediacaran fauna near Adelaide, Australia.


  
574,000,000 YBN
96) First neuron, nerve cell, and nervous system evolves in bilaterians.



  
570,000,000 YBN
95) Fluid filled cavity, coelom evolves in early bilaterians.



  
570,000,000 YBN
105) Deuterostomes evolve. This is the beginning of the Subkingdom
Deuterostomia and Infrakingdom "Coelomopora" (Ambulacraria) with the two Phyla
"Hemichordata" (acorn worms) and "Echinodermata" (sea cucumbers, sea urchins,
starfish).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
PHYLUM †Vetulicolia Shu et al., 2001
INFRAKINGDOM
Coelomopora (Marcus, 1958) Cavalier-Smith, 1998
INFRAKINGDOM Chordonia
(Haeckel, 1874) Cavalier-Smith, 1998



  
570,000,000 YBN
311) Ecdysozoa phylum Chaetognatha (Arrow Worms) evolves.



  
570,000,000 YBN
345) Deuterostome Coelomorpha Phylum Hemichordonia (acorn worms) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
PHYLUM †Vetulicolia Shu et al., 2001
INFRAKINGDOM
Coelomopora (Marcus, 1958) Cavalier-Smith, 1998
PHYLUM Echinodermata
Klein, 1734 ex De Brugière, 1789 - echinoderms
PHYLUM Hemichordata (Bateson,
1885) auct. - hemichordates


  
570,000,000 YBN
346) Deuterostome Coelomorpha Phylum Echinodermata (sea cucumbers, sea urchins,
sand dollars, star fish) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
PHYLUM †Vetulicolia Shu et al., 2001
INFRAKINGDOM
Coelomopora (Marcus, 1958) Cavalier-Smith, 1998
PHYLUM Echinodermata
Klein, 1734 ex De Brugière, 1789 - echinoderms
PHYLUM Hemichordata (Bateson,
1885) auct. - hemichordates


  
565,000,000 YBN
98) First circulatory system and red blood cells evolve in bilaterian worms.



  
565,000,000 YBN
327) Infrakingdom Platyzoa (includes Superphylum Gnathifera {gnathiferans},
Phylum Gastrotricha {gastrotrichs}, and Phylum Platyhelminthes {flatworms})
evolve.




  
565,000,000 YBN
347) Deuterostome Phylum Chordata evolves. Chordata is a very large group that
contains all fish, amphibians, reptiles and mammals.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Tunicata
Lamarck, 1816 - tunicates
SUBPHYLUM Cephalochordata - lancelets
SUBPHYLUM
Vertebrata Cuvier, 1812 - vertebrates


  
565,000,000 YBN
348) Deuterstome Chordata Subphylum Tunicata (tunicates {sea squirts}) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Tunicata
Lamarck, 1816 - tunicates
SUBPHYLUM Cephalochordata - lancelets
SUBPHYLUM
Vertebrata Cuvier, 1812 - vertebrates


  
562,000,000 YBN
99) Segmentation evolves.



  
561,000,000 YBN
100) Filter feeding, filtering food and oxygen from water through a digestive
system, evolves in segmented worms.




  
560,000,000 YBN
117) Oldest fossil of chordate, Ediacaran fossil.


  
560,000,000 YBN
330) The two Ecdysozoa Superphyla Ashelminthes (round worms, horsehair worms,
priapulids) and Pananthropoda (arthropods, onychophorans, tardigrades)
separate.




  
560,000,000 YBN
349) Deuterstome Chordata Subphylum Cephalochordata (lancelets) evolves. This
is the first fish.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Tunicata
Lamarck, 1816 - tunicates
SUBPHYLUM Cephalochordata - lancelets
SUBPHYLUM
Vertebrata Cuvier, 1812 - vertebrates


  
559,000,000 YBN
103) First gastrotrichs evolve.

  
550,000,000 YBN
108) Cyclomedusa Ediacaran fossil.
  
550,000,000 YBN
109) Kimbrella Ediacaran (Vendian) fossil.
  
550,000,000 YBN
110) Eorporpita Ediacaran (Vendian) fossil.
  
550,000,000 YBN
111) (Helminth) Worm tracks Ediacaran (Vendian) fossil.
  
550,000,000 YBN
112) Dickinsonia Ediacaran (Vendian) fossil.
  
550,000,000 YBN
113) Pteridinium Ediacaran (Vendian) fossil.
  
550,000,000 YBN
114) Spriggina Ediacaran (Vendian) fossil.
  
550,000,000 YBN
115) Charnia, Ediacaran (Vendian) fossil.
  
550,000,000 YBN
116) Nemiana, Ediacaran (Vendian) fossil.
  
550,000,000 YBN
118) Tribrachidium, Ediacaran fossil.
  
550,000,000 YBN
119) Arkarua, Ediacaran fossil.
  
550,000,000 YBN
157) Amino acid sequence comparison shows the chordate line separating from
echinoderm line here at 550 mybn (first chordates).


  
550,000,000 YBN
328) Ecdysozoa Superphylum "Ashelminthes" evolves. This includes the 5 Phyla:

Kinorhyncha (kinorhynchs),
Loricifera (loriciferans),
Nematoda (round worms),
Nematomorpha (horsehair
worms),
Priapulida (priapulids).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 - protostomes
INFRAKINGDOM Ecdysozoa Aguinaldo et al., 1997 ex
Cavalier-Smith, 1998 - ecdysozoans
SUPERPHYLUM Aschelminthes
PHYLUM
Priapulida Théel, 1906 - priapulids
PHYLUM Kinorhyncha Reinhard, 1887 -
kinorhynchs
PHYLUM Loricifera Kristensen, 1983 - loriciferans
PHYLUM Nematoda
(Rudolphi, 1808) Lankester, 1877 - round worms
PHYLUM Nematomorpha
Vejdovsky, 1886 - horsehair worms


  
550,000,000 YBN
329) Platyzoa Superphylum "Gnathifera" evolves. This includes the 5 Phyla:
Gnat
hostomulida (gnathostomulids),
Cycliophora (cycliophorans),
Micrognathozoa,
Rotifera (rotifers),
Acanthocephala (acanthocephalans).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 - protostomes
INFRAKINGDOM Platyzoa Cavalier-Smith, 1998

SUPERPHYLUM Gnathifera - gnathiferans
PHYLUM Gnathostomulida (Ax, 1956) Riedl,
1969 - gnathostomulids
PHYLUM Cycliophora Funch & Kristensen, 1995 - cycliophorans

PHYLUM Micrognathozoa (Kristensen & Funch, 2000)
PHYLUM Rotifera Cuvier,
1798 - rotifers
PHYLUM Acanthocephala Kohlreuther, 1771 - acanthocephalans


  
547,000,000 YBN
331) The Protostome Infrakingdom Lophotrochozoa evolves. This includes
brachiopods, bryozoans, clams, squids and octopuses (cephalopods), and snails.

This
infrakingdom is made of:
Superphylum Lophophorata,
Phylum Bryozoa (bryozoans),
Phylum Entoprocta
(entoprocts),
Superphylum Eutrochozoa.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals

SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH
Protostomia Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa"
(lophotrochozoans)
SUPERPHYLUM Lophophorata
PHYLUM Bryozoa Ehrenberg, 1831 (bryozoans)
PHYLUM
Entoprocta (Nitsche, 1869) (entoprocts)
SUPERPHYLUM Eutrochozoa


  
547,000,000 YBN
332) The Lophotrochozoa Superphylum Lophophorata evolves. This includes the
two Phyla Phoronida (phoronids) and Brachiopoda (brachiopods {clams, oysters,
muscles}).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Lophophorata
PHYLUM Phoronida (phoronids)
PHYLUM Brachiopoda (brachiopods)


  
547,000,000 YBN
333) The Lophotrochozoa Phyla Phoronida (phoronids) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Lophophorata
PHYLUM Phoronida (phoronids)
PHYLUM Brachiopoda (brachiopods)


  
547,000,000 YBN
334) The Lophotrochozoa Phylum Brachiopoda (brachiopods {clams, oysters,
muscles}) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Lophophorata
PHYLUM Phoronida (phoronids)
PHYLUM Brachiopoda (brachiopods)


  
545,000,000 YBN
335) The Lophotrochozoa Phylum Entoprocta (entoprocts) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
PHYLUM Entoprocta
(Nitsche, 1869) - entoprocts


  
543,000,000 YBN
53) End Precambrian Eon, start Phanerozoic Eon. End Proterozoic Era, start
Paleozoic Era.




  
543,000,000 YBN
104) The Platyzoa Phyla Platyhelminthes (flatworms) and Gastrotricha
(gastrotrichs) evolve.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM Platyzoa Cavalier-Smith, 1998

SUPERPHYLUM Gnathifera - gnathiferans
PHYLUM Gastrotricha Metschnikoff, 1864 -
gastrotrichs
PHYLUM Platyhelminthes Gegenbaur, 1859 - flatworms


  
543,000,000 YBN
120) Start Cambrian period (543-490 mybn).



  
543,000,000 YBN
336) The Lophotrochozoa Phylum Bryozoa (Bryozoans or moss animals) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
PHYLUM Bryozoa
Ehrenberg, 1831 - bryozoans


  
543,000,000 YBN
337) The Ecdysozoa Superphylum Panarthropoda (Arthropods, Onychophora,
Tardigrada) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM Ecdysozoa Aguinaldo et al., 1997 ex
Cavalier-Smith, 1998 - ecdysozoans
SUPERPHYLUM Panarthropoda
PHYLUM Tardigrada
(Spallanzani, 1777) Ramazzotti, 1962 - tardigrades
PHYLUM Onychophora -
onychophorans
PHYLUM Arthropoda Latreille, 1829 - arthropods


  
543,000,000 YBN
338) The Ecdysozoa Phylum Arthropoda (insects, crustaceans) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM Ecdysozoa Aguinaldo et al., 1997 ex
Cavalier-Smith, 1998 - ecdysozoans
SUPERPHYLUM Panarthropoda
PHYLUM Tardigrada
(Spallanzani, 1777) Ramazzotti, 1962 - tardigrades
PHYLUM Onychophora -
onychophorans
PHYLUM Arthropoda Latreille, 1829 - arthropods


  
543,000,000 YBN
339) The Ecdysozoa Phylum Onychophora (onychophorans) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM Ecdysozoa Aguinaldo et al., 1997 ex
Cavalier-Smith, 1998 - ecdysozoans
SUPERPHYLUM Panarthropoda
PHYLUM Tardigrada
(Spallanzani, 1777) Ramazzotti, 1962 - tardigrades
PHYLUM Onychophora -
onychophorans
PHYLUM Arthropoda Latreille, 1829 - arthropods


  
543,000,000 YBN
340) The Ecdysozoa Phylum Tardigrada (tardigrades) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM Ecdysozoa Aguinaldo et al., 1997 ex
Cavalier-Smith, 1998 - ecdysozoans
SUPERPHYLUM Panarthropoda
PHYLUM Tardigrada
(Spallanzani, 1777) Ramazzotti, 1962 - tardigrades
PHYLUM Onychophora -
onychophorans
PHYLUM Arthropoda Latreille, 1829 - arthropods


  
542,000,000 YBN
131) First shell (or skeleton) evolves.



  
541,000,000 YBN
102) The Lophotrochozoa Superphylum Eutrochozoa (molluscs, ribbon, peanut,
spoon, and segmented worms) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Eutrochozoa
PHYLUM Nemertea Schultze - ribbon worms
PHYLUM Sipuncula
(Raffinesque, 1814) Sedgwick, 1898 - peanut worms
PHYLUM Mollusca
(Linnaeus, 1758) Cuvier, 1795 - molluscs
PHYLUM †Hyolitha
PHYLUM Echiura
Sedgwick, 1898 - spoon worms, echiurans
PHYLUM Annelida Lamarck, 1809 -
segmented worms


  
541,000,000 YBN
132) Archaeocyatha (early sponges) evolve.



  
541,000,000 YBN
341) The Lophotrochozoa Phylum Nemertea (ribbon worms) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Eutrochozoa
PHYLUM Nemertea Schultze - ribbon worms
PHYLUM Sipuncula
(Raffinesque, 1814) Sedgwick, 1898 - peanut worms
PHYLUM Mollusca
(Linnaeus, 1758) Cuvier, 1795 - molluscs
PHYLUM †Hyolitha
PHYLUM Echiura
Sedgwick, 1898 - spoon worms, echiurans
PHYLUM Annelida Lamarck, 1809 -
segmented worms


  
540,000,000 YBN
133) Earliest trilobite fossil.



  
539,000,000 YBN
342) The Lophotrochozoa Phylum Mollusca (brachiopods, bryozoans, clams,
mussels, squids and octopuses {cephalopods}, and snails) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Eutrochozoa
PHYLUM Nemertea Schultze - ribbon worms
PHYLUM Sipuncula
(Raffinesque, 1814) Sedgwick, 1898 - peanut worms
PHYLUM Mollusca
(Linnaeus, 1758) Cuvier, 1795 - molluscs
PHYLUM †Hyolitha
PHYLUM Echiura
Sedgwick, 1898 - spoon worms, echiurans
PHYLUM Annelida Lamarck, 1809 -
segmented worms


  
537,000,000 YBN
343) The Lophotrochozoa Phylum Annelida (segmented worms) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Eutrochozoa
PHYLUM Nemertea Schultze - ribbon worms
PHYLUM Sipuncula
(Raffinesque, 1814) Sedgwick, 1898 - peanut worms
PHYLUM Mollusca
(Linnaeus, 1758) Cuvier, 1795 - molluscs
PHYLUM †Hyolitha
PHYLUM Echiura
Sedgwick, 1898 - spoon worms, echiurans
PHYLUM Annelida Lamarck, 1809 -
segmented worms


  
537,000,000 YBN
344) The Lophotrochozoa Phylum Sipuncula (peanut worms) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Protostomia
Grobben, 1908 (protostomes)
INFRAKINGDOM "Lophotrochozoa" (lophotrochozoans)
SUPERPHYLUM
Eutrochozoa
PHYLUM Nemertea Schultze - ribbon worms
PHYLUM Sipuncula
(Raffinesque, 1814) Sedgwick, 1898 - peanut worms
PHYLUM Mollusca
(Linnaeus, 1758) Cuvier, 1795 - molluscs
PHYLUM †Hyolitha
PHYLUM Echiura
Sedgwick, 1898 - spoon worms, echiurans
PHYLUM Annelida Lamarck, 1809 -
segmented worms


  
530,000,000 YBN
350) Deuterstome Chordata Subphylum Vertebrata evolves. This Subphylum
contains most fish, all amphibians, reptiles, and mammals.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
CLASS Agnatha
INTRAPHYLUM Gnathostomata
auct. - jawed vertebrates


  
530,000,000 YBN
351) Subphylum Vertebrata jawless fish (agnatha) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
CLASS Agnatha
INTRAPHYLUM Gnathostomata
auct. - jawed vertebrates


  
530,000,000 YBN
386) Oldest fossil vertebrate and fish.
Haikouichthys ercaicunensis: About 25 mm in
length.



  
520,000,000 YBN
148) Hexactinellid sponge from the Hetang Formation, Southern China.

  
520,000,000 YBN
205) Dinoflagellate biological markers measured in Kopli quarry, Tallinn,
Estonia.




  
507,000,000 YBN
140) Aysheaia (onychophoran, also described as lobopod) fossil, from Burgess
shale.



  
507,000,000 YBN
142) Hallucigenia fossil, from Burgess shale.

  
507,000,000 YBN
143) Xenusion (onychophoran, also described as lobopod) fossil, from early
Cambrian sandstones of eastern Europe.

  
507,000,000 YBN
145) Priapulid worm fossils of Burgess Shale.


  
507,000,000 YBN
146) Opabinia fossils of Burgess Shale.


  
507,000,000 YBN
147) Animalocaris fossils of Burgess Shale.


  
507,000,000 YBN
149) Marrella (Arthropod) fossils in Burgess Shale.



  
505,000,000 YBN
74) Oldest fossil of an artropod moulting.


  
500,000,000 YBN
230) Ascomycota Fungi "Pyrenomycetes" (head scab fungus, orange bread mold,
rice blast fungus) and "Plectomycetes" (aspergillus, penicilin fungus,
coccidiodomycosis fungus) evolve.

Genetic comparison shows the Ascomycota Fungi
"Pyrenomycetes" (head scab fungus, orange bread mold, rice blast fungus) and
"Plectomycetes" (aspergillus, penicilin fungus, coccidiodomycosis fungus)
evolving now.


  
490,000,000 YBN
121) Start Ordovician (490-443 mybn), end Cambrian period (543-490 mybn).



  
475,000,000 YBN
90) Genetic comparison shows the ancestor of all plants (Kingdom Plantae)
evolving at this time (in the view that algae are protists and not plants).

Genetic
comparison shows the ancestor of all plants (Kingdom Plantae) evolving at this
time (in the view that algae are single and multicellular protists and not
plants).



  
475,000,000 YBN
232) Genetic comparison shows the non-vascular plant and vascular plant lines
splitting now.




  
475,000,000 YBN
233) Genetic comparison shows Liverworts (Plant Division Marchantiophyta)
evolving now.



  
475,000,000 YBN
244) Genetic comparison shows non-vascular plants (Bryophytes) (Liverworts,
Hornworts, Mosses) evolving now.

Many people view these plants and the beginning of
the Plant kingdom and algae as being in the Protista kingdom.
These plants lack vascular
tissue that circulates liquids. They neither flower nor produce seeds,
reproducing via spores.
The order these three divisions evolved in is not fully known.

Liverwo
rts 9,000
Hornworts 100 species
Mosses 15,000


  
475,000,000 YBN
352) Subphylum Vertebrata jawless fish lampreys and hagfish lines separate.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
CLASS Agnatha
INTRAPHYLUM Gnathostomata
auct. - jawed vertebrates


  
470,000,000 YBN
234) Genetic comparison shows Hornworts (division Anthocerotophyta) evolving
now.



  
464,000,000 YBN
398) Earliest fossil spore belonging to land plants.
These spores look like
the spores of living liverworts.



  
460,000,000 YBN
84) Earliest fungi fossil.


  
460,000,000 YBN
235) Genetic comparison shows Mosses (division Bryophyta) evolving now.
15,000
species.


  
460,000,000 YBN
353) Jawed vertebrates (Infraphylum Gnathostomata) evolve. This large group
includes all jawed fish, all amphibians, reptiles, and mammals.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS †Placodermi McCoy, 1848
CLASS Chondrichthyes
- cartilaginous fishes
CLASS †Acanthodii
CLASS Osteichthyes
Huxley, 1880
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods


  
460,000,000 YBN
354) Jawed vertebrate (Infraphylum Gnathostomata) Class Chondrichthyes
(cartilaginous fishes) evolve.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS †Placodermi McCoy, 1848
CLASS Chondrichthyes
- cartilaginous fishes
CLASS †Acanthodii
CLASS Osteichthyes
Huxley, 1880
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods


  
450,000,000 YBN
106) First chordates. The Chordata phylum includes all tunicates, fishes,
amphibians, reptiles, birds, and mammals. The living chordate with the oldest
DNA design are tunicates.




  
450,000,000 YBN
158) Amino acid sequence comparison shows the gnathostome (vertebrates with a
jaw bone) line separating from lamprey line here at 450 mybn (first
gnathostome).


  
443,000,000 YBN
122) Start Silurian period (443-417), end Ordovician period (490-443 mybn).



  
440,000,000 YBN
360) In the Jawed Fishes, the Ray-finned fishes (Subclass Actinopterygii)
evolve.

Ray-finned fishes (Subclass Actinopterygii) are in Class Osteichthyes.
DOMAIN Eukaryota -
eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888)
Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben, 1908 -
deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM
Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates
CLASS
Osteichthyes Huxley, 1880
SUBCLASS Actinopterygii - ray-finned
fishes
INFRACLASS Cladistia
INFRACLASS Actinopteri


  
428,000,000 YBN
401) Oldest fossil of vascular land plants, Cooksonia.
Oldest fossil of
vascular land plants, Cooksonia pertoni.

They have been found in an area stretching from Siberia to the Eastern USA, and
in Brazil. They are found mostly in the area of Euramerica, and most of the
type specimens are from Britain.

Cooksonia were very small plants, only a few centimetres tall, and had a simple
structure: They didn't have leaves, flowers or seeds. They had a simple
stalk, that branched a few times. Each branch ended in a sporangium, a rounded
structure that contained the spores. No specimen has been found attached to
roots. Either it connected to the ground with very fine root hairs, the fossils
are of fragments, or something entirely unanticipated. Some specimens have a
dark stripe in the centre of their stalks which is interpreted as being the
remains of water carrying tissue. Not all specimens have this stripe, either
some Cooksonia lacked vasular tissue, or it was destroyed in the fossilization
process.

Oldest fossil of vascular land plants, Cooksonia pertoni, from
England, UK.

They have been found in an area stretching from Siberia to the Eastern USA, and
in Brazil. They are found mostly in the area of Euramerica, and most of the
type specimens are from Britain.

Cooksonia were small, a few centimetres tall, and had a simple structure: They
didn't have leaves, flowers, or seeds. They had a simple stalk, that branched
a few times. Each branch ended in a sporangium, a rounded structure that
contained the spores. No specimen has been found attached to roots. Either it
connected to the ground with very fine root hairs, the fossils are of
fragments, or something entirely unanticipated. Some specimens have a dark
stripe in the centre of their stalks which is interpreted as being the remains
of water carrying tissue. Not all specimens have this stripe, either some
Cooksonia lacked vasular tissue, or it was destroyed in the fossilization
process.

The relationships between the known species of Cooksonia and modern plants
remain unclear. They appear to represent plants that are near to the branching
between Rhyniophyta and to the club mosses. It is considered likely that
Cooksonia is not a clade but rather represents an evolutionary grade.

Five species of Cooksonia have been clearly identified. C. pertoni, C.
hemisphaerica, C. cambrensis, C. caledonica and C. paranensis. They are
distiguished primarily by the shape of the sporangia.

The first Cooksonia were discovered by W.H. Lang in 1937 and named in honour of
Isabel Cookson, with whom he had collaborated.

Cooksonia branches dichotomously (from 1 into 2 branches only).


  
428,000,000 YBN
402) Oldest fossil land animal, the millipede Pneumodesmus.




  
425,000,000 YBN
377) Coelacanths evolve.
2 living species known.
DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia
Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983
- bilaterians
BRANCH Deuterostomia Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia
(Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM Chordata Bateson, 1885 -
chordates
SUBPHYLUM Vertebrata Cuvier, 1812 - vertebrates
INFRAPHYLUM
Gnathostomata auct. - jawed vertebrates
CLASS Osteichthyes Huxley, 1880

SUBCLASS Sarcopterygii
INFRACLASS Crossopterygii
ORDER
Actinistia - coelacanths


  
417,000,000 YBN
123) Start Devonian period (417-354 mybn), end Silurian period (443-417 mybn).



  
417,000,000 YBN
378) Lungfishes evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Sarcopterygii
ORDER Dipnoi - lungfishes


  
412,000,000 YBN
403) Oldest fossil lung fish.




  
409,000,000 YBN
404) Oldest fossil shark.




  
400,000,000 YBN
85) Earliest lichen fossil.


  
400,000,000 YBN
159) Amino acid sequence comparison shows the tetrapod (4 leg) line separating
from the fish line here at 400 mybn (first tetrapod).


  
400,000,000 YBN
236) Genetic comparison shows the oldest line of living vascular plants from
the Division "Lycophyta" evolving now.

Genetic comparison shows the oldest line of
living vascular plants (Tracheophytes) from the Division "Lycophyta" evolving
now.

1,200 species.

  
400,000,000 YBN
399) Earliest fossil of an insect.
This fossil also could have been winged.



  
390,000,000 YBN
355) Cartilaginous Fishes (Class Chondrichthyes) Subclass Subterbranchialia and
Subclass Elasmobranchii (shark-like fishes) separate.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Chondrichthyes - cartilaginous fishes
SUBCLASS
Elasmobranchii - shark-like fishes
SUBCLASS Subterbranchialia


  
390,000,000 YBN
356) Subclass Subterbranchialia Superorder Holocephali (chimaeras: eg. elephant
fish) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Chondrichthyes - cartilaginous fishes
SUBCLASS
Elasmobranchii - shark-like fishes
SUBCLASS Subterbranchialia

SUPERORDER Holocephali


  
380,000,000 YBN
243) Genetic comparison shows the Fern line and the line that leads to Seed
Plants (Gymnosperms and Angiosperms) separating now.




  
380,000,000 YBN
246) Genetic comparison shows the Spore producing and Seed producing plant
lines separating now.

Genetic comparison shows the Spore producing (ferns and all
earlier plants) and Seed producing (Spermatophyta, Gymnosperms and Angiosperms)
plant lines separating now.



  
380,000,000 YBN
405) Oldest fossil large trees. First forests.




  
380,000,000 YBN
406) Oldest fossil spider.




  
375,000,000 YBN
407) Oldest fossil amphibian, and land vertebrate.
Oldest fossil amphibian,
Acanthostega , from Greenland Also, the oldest evidence of land vertebrates.




  

SCIENCE
375,000,000 YBN
2599) The Tiktaalik (TiK Tol iK), a genus of extinct sarcopterygian
(lobe-finned) fish with many features akin to those of tetrapods (four-legged
animals) lives now.

Although the body scales, fin rays, lower jaw and palate are comparable to
those in more primitive sarcopterygians, the tiktaalik also has a shortened
skull roof, a modified ear region, a mobile neck, a functional wrist joint, and
other features that predict tetrapod conditions. The morphological features and
geological setting of (tiktaalik fossils) suggest a life in shallow-water,
marginal and (earth surface) habitats.

Ellesmere Island, Nunavut, in northern Canada  
365,000,000 YBN
160) Amino acid sequence comparison shows the amniote () line separating from
the amphibian line here at 365 mybn (first amniote).


  
360,000,000 YBN
237) Genetic comparison shows Ferns (Plant Division "Pteridophyta") evolving
now.

Genetic comparison shows the Plant Division "Pteridophyta" (Ferns) evolving
now.
Whisk and Ophioglossiod ferns, Marattiod ferns, Horsetails, Lepto. ferns.

Lepto.
ferns 11,000
Horsetails 15
Marattioid ferns 240
Ophioglossoid ferns 110
Whisk 15


  
360,000,000 YBN
408) Devonian mass extinction caused by ice age.




  
354,000,000 YBN
124) Start Carboniferous period (354-290 mybn), end Devonian period (417-354
mybn).




  
350,000,000 YBN
361) In the Ray-finned fishes Superdivision Chondrostei (sturgeons and
paddlefish) evolves.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri


  
350,000,000 YBN
362) In the Ray-finned fishes Infradivsion Cladistia (Bichirs) evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri


  
340,000,000 YBN
379) Tetrapods evolve.
(Superclass Tetrapoda)
DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus,
1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 -
bilaterians
BRANCH Deuterostomia Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia
(Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM Chordata Bateson, 1885 -
chordates
SUBPHYLUM Vertebrata Cuvier, 1812 - vertebrates
INFRAPHYLUM
Gnathostomata auct. - jawed vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930
- tetrapods


  
340,000,000 YBN
380) Amphibians (Caecillians, frogs, toads, Salamanders) evolve.
(Superclass
Tetrapoda, Class Amphibia)

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 -
animals
SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH
Deuterostomia Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM
Vertebrata Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
CLASS
Amphibia Linnaeus, 1758 - amphibians


  
330,000,000 YBN
409) Oldest fossil conifer.




  
325,000,000 YBN
381) The Amphibians Caecillians evolve.
(Superclass Tetrapoda, Class Amphibia)
DOMAIN Eukaryota
- eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888)
Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben, 1908 -
deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM
Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates

SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
CLASS Amphibia
Linnaeus, 1758 - amphibians
SUBCLASS Lissamphibia Haeckel, 1866

ORDER Gymnophiona Rafinesque-Schmaltz, 1814


  
320,000,000 YBN
238) Genetic comparison shows the oldest living Gymnosperms from the Plant
Kingdom evolving now.

Genetic comparison shows the oldest living Gymnosperms (Greek
for "Naked Seed"), Cycads, from the Plant Kingdom evolving now. These are the
first seed bearing plants.

Gymnosperm Plant Divisions are:
Pinophyta - Conifers "Pinaceae" 220 "Other conifers"
400 species
Ginkgophyta - Ginkgo 1 species
Cycadophyta - Cycads 130 species
Gnetophyta - Gnetum,
Ephedra, Welwitschia 80 species



  
318,000,000 YBN
242) Genetic comparison shows the Gymnosperms and Angiosperms lines separating
now.




  
315,000,000 YBN
410) Oldest fossil reptile.
Hylonomus was a small lizard-like reptile that was
trapped in the trunk of a swamp tree in what is now Nova Scotia , Canada.




  
315,000,000 YBN
411) Oldest fossil of flying insect (mayfly?).
Oldest fossil of flying insects
(unless Devonian Rhyniognatha had wings). Fossil wings on giant mayflies,
dragonflys, and dragonfly-like arthropods.




  
315,000,000 YBN
453) Allegheny mountains form as a result of the collision of Europe and
eastern North America.





  
310,000,000 YBN
384) Egg evolves.
This group, the Amniota, will branch into the 3 major Classes:
Reptiles (Sauropsida), Birds (Aves), and Mammals (Synapsida).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota


  
310,000,000 YBN
385) Reptiles evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida


  
305,000,000 YBN
382) The Amphibians Frogs and Toads evolve.
(Superclass Tetrapoda, Class Amphibia)
DOMAIN
Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria
(Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben,
1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998

PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates

SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
CLASS Amphibia
Linnaeus, 1758 - amphibians
SUBCLASS Lissamphibia Haeckel, 1866

ORDER Anura (Rafinesque, 1815) Hogg, 1839:152


  
305,000,000 YBN
383) Amphibians Salamanders evolve.
(Superclass Tetrapoda, Class Amphibia)
DOMAIN Eukaryota -
eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888)
Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben, 1908 -
deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM
Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates

SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
CLASS Amphibia
Linnaeus, 1758 - amphibians
SUBCLASS Lissamphibia Haeckel, 1866

ORDER Caudata Scopoli, 1777


  
300,000,000 YBN
162) Amino acid sequence comparison shows that the common ancestor of all
mammals, birds, and reptiles dates to here at 300 mybn.


  
300,000,000 YBN
387) Turtles, Tortoises and Terrapins evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Anapsida

ORDER Testudines - turtles


  
290,000,000 YBN
125) Start Permian period (290-248 mybn), end Carboniferous period (354-290
mybn).




  
290,000,000 YBN
239) Genetic comparison shows the second oldest living Gymnosperm, Ginkgo from
the Plant Kingdom evolving now.

Ginkgophyta - Ginkgo 1 species

  
280,000,000 YBN
388) Anapsids (iguanas and snakes) and diapsids (crocodiles) separate.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Diapsida

INFRACLASS Lepidosauromorpha
SUPERORDER Lepidosauria™

ORDER Sphenodontida
FAMILY Sphenodontidae™ -
tuataras


  
270,000,000 YBN
240) Genetic comparison shows the third oldest living Gymnosperms, Conifers
(Plant division "Pinophyta") evolving now.

Pinophyta - Conifers "Pinaceae" 220
"Other conifers" 400 species

Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Families:
Pinaceae - Pine family
Araucariaceae - Araucaria family
Podocarpaceae - Yellow-wood family
ciadopitya
ceae - Umbrella-pine family
Cupressaceae - Cypress family (includes Sequoia, Redwoods,
Cypress, Alerce {Second oldest})
Cephalotaxaceae - Plum-yew family
Taxaceae - Yew family


  
260,000,000 YBN
363) In the Ray-finned fishes Infradivision Actinopteri evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri


  
260,000,000 YBN
364) In the Ray-finned fishes Infradivision Actinopteri, Gars evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri


  
255,000,000 YBN
389) Tuataras evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Diapsida

INFRACLASS Lepidosauromorpha
SUPERORDER Lepidosauria™

ORDER Sphenodontida
FAMILY Sphenodontidae™ -
tuataras


  
251,000,000 YBN
452) The supercontinent Pangea forms.




  
250,000,000 YBN
241) Genetic comparison shows the fourth oldest living Plant Division
"Gnetales" evolving now.

Gnetophyta - Gnetum, Ephedra, Welwitschia 80 species.

  
250,000,000 YBN
396) The Permian mass extinction event happens. This is the most devastating
mass extinction event in the history of earth.

Trilobites become extinct.



  
248,000,000 YBN
54) End Paleozoic Era, start Mesozoic Era.



  
248,000,000 YBN
126) Start Triassic period (248-206 mybn), end Permian period (290-248 mybn).



  
245,000,000 YBN
392) Crocodiles, allegators, caimans evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Diapsida

INFRACLASS Archosauromorpha
DIVISION Archosauria

SUBDIVISION Crurotarsi - crurotarsans
SUPERORDER
Crocodylomorpha
ORDER Crocodylia™ - crocodiles


  
245,000,000 YBN
393) Birds evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Aves Linnaeus, 1758 - birds


  
240,000,000 YBN
365) Actinopteri Superdivision Neopterygii evolves.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii


  
240,000,000 YBN
366) In Superdivision Neopterygii, Subdivision Halecomorphi, Bow fish
(Amiiformes) evolve.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii


  
240,000,000 YBN
367) Bow fish evolve.
In Superdivision Neopterygii, Division Halecostomi, Subdivision
Halecomorphi, Bow fish (Amiiformes) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia
Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983
- bilaterians
BRANCH Deuterostomia Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia
(Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM Chordata Bateson, 1885 -
chordates
SUBPHYLUM Vertebrata Cuvier, 1812 - vertebrates
INFRAPHYLUM
Gnathostomata auct. - jawed vertebrates
CLASS Osteichthyes Huxley, 1880

SUBCLASS Actinopterygii - ray-finned fishes
INFRACLASS
Cladistia
INFRACLASS Actinopteri
SUPERDIVISION Neopterygii


  
228,000,000 YBN
412) Oldest dinosaur fossil, Eorapter was found in South America.
Oldest
dinosaur fossil. Eoraptor was found in South America . This little dinosaur was
a cat-sized meat eater.




  
220,000,000 YBN
400) Oldest mammal fossil.
This is a fingernail-sized skull found in Texas.



  
215,000,000 YBN
428) Oldest Pterosaur fossil.




  
210,000,000 YBN
368) Subdivision Teleostei (eels, herrings, anchovies, carp, minnows, piranha,
salmon, trout, pike, perch, seahorse, cod) evolves.

In Superdivision Neopterygii,
Division Halecostomi, Subdivision Halecomorphi, Bow fish (Amiiformes) evolve.

DOMAIN
Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria
(Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben,
1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998

PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates
CLASS
Osteichthyes Huxley, 1880
SUBCLASS Actinopterygii - ray-finned
fishes
INFRACLASS Cladistia
INFRACLASS Actinopteri

SUPERDIVISION Neopterygii


  
210,000,000 YBN
369) Bonytongues evolve.
In Subdivision Teleostei Bonytongues evolve.
DOMAIN Eukaryota -
eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM Bilateria (Hatschek, 1888)
Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia Grobben, 1908 -
deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith, 1998
PHYLUM
Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata Cuvier, 1812 -
vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed vertebrates
CLASS
Osteichthyes Huxley, 1880
SUBCLASS Actinopterygii - ray-finned
fishes
INFRACLASS Cladistia
INFRACLASS Actinopteri

SUPERDIVISION Neopterygii
DIVISION Halecostomi

SUBDIVISION Teleostei


  
210,000,000 YBN
390) Iguanas, chamaeleons, spiny lizards evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Diapsida

INFRACLASS Lepidosauromorpha
SUPERORDER Lepidosauria™

ORDER Squamata
SUBORDER Lacertilia

INFRAORDER Iguania


  
210,000,000 YBN
391) Snakes, Skinks, Geckos evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
SUPERCLASS Tetrapoda Goodrich, 1930 - tetrapods
SERIES
Amniota
CLASS Sauropsida
SUBCLASS Diapsida

INFRACLASS Lepidosauromorpha
SUPERORDER Lepidosauria™

ORDER Squamata
SUBORDER Serpentes (Linnaeus,
1758) - snakes


  
210,000,000 YBN
413) Oldest turtle fossil.
Oldest turtle fossil, Proganochelys.



  
209,500,000 YBN
489) Triconodonta (extinct mammals) evolve.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Triconodonta



  
206,000,000 YBN
127) Start Jurassic period (206-144 mybn), end Triassic period (248-206 mybn).



  
200,000,000 YBN
370) Eels and tarpons (Elopocephala) evolve.
In Subdivision Teleostei Eels and tarpons
(Elopocephala) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals

SUBKINGDOM Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH
Deuterostomia Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM
Vertebrata Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
199,000,000 YBN
414) End of Triassic mass extinction, because of climate (temperature?,
weather?) changes. Large outpourings of lava from break-up of Pangea may have
caused climate change.

50% of life went extinct, including thecodonts and
synapsids.




  
190,000,000 YBN
357) Subclass Elasmobranchii (shark-like fishes) divides into 2 divisions
Squalea (rays, skates) and Galeomorphii (great white, hammerhead, nurse, sand
tiger sharks).


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Chondrichthyes - cartilaginous fishes
SUBCLASS
Elasmobranchii - shark-like fishes
INFRACLASS Euselachii

COHORT Neoselachii
DIVISION Galeomorphii
DIVISION
Squalea


  
190,000,000 YBN
358) Division Squalea (rays, skates) evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Chondrichthyes - cartilaginous fishes
SUBCLASS
Elasmobranchii - shark-like fishes
INFRACLASS Euselachii

COHORT Neoselachii
DIVISION Galeomorphii
DIVISION
Squalea
ORDER Hexanchiformes - cowsharks and frilled sharks

ORDER Echinorhiniformes
ORDER Squaliformes - dogfish
sharks and relatives
SUPERORDER Hypnosqualea

SUPERORDER Batoidea - rays


  
190,000,000 YBN
359) Division Galeomorphii (great white, hammerhead, nurse, sand tiger sharks)
evolve.


DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Chondrichthyes - cartilaginous fishes
SUBCLASS
Elasmobranchii - shark-like fishes
INFRACLASS Euselachii

COHORT Neoselachii
DIVISION Galeomorphii
ORDER
Carcharhiniformes - ground sharks
ORDER Heterodontiformes -
bullhead sharks
ORDER Lamniformes - mackerel sharks and
relatives
ORDER Orectolobiformes - carpet sharks

DIVISION Squalea


  
190,000,000 YBN
371) Herrings and anchovies evolve.
Herrings and anchovies (Division Clupeomorpha)
evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
185,000,000 YBN
194) Oldest diatom (Heterokonts or Chromalveolates) fossils.



  
180,000,000 YBN
456) First mammals, Monotremes evolves. Monotremes lay eggs and are the
oldest warm blooded species of record.

Order: Monotremata (C.L. Bonaparte, 1837)
or
Su
bclass Prototheria (Gill, 1872:vi)

Biota
Domain Eukaryota - eukaryotes
Kingdom Animalia Linnaeus, 1758 - animals
Subkingdom
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
Branch Deuterostomia
Grobben, 1908 - deuterostomes
Infrakingdom Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
Phylum Chordata Bateson, 1885 - chordates

Subphylum Vertebrata Cuvier, 1812 - vertebrates
Infraphylum Gnathostomata
auct. - jawed vertebrates
Superclass Tetrapoda Goodrich, 1930 -
tetrapods
Series Amniota
Mammaliaformes Rowe, 1988

Class Mammalia Linnaeus, 1758 - mammals

Subclass Prototheria Gill, 1872:vi
Order Platypoda (Gill,
1872) McKenna in Stucky & McKenna in Benton, ed., 1993:740

Order Tachyglossa (Gill, 1872) McKenna in Stucky & McKenna in Benton, ed.,
1993:740



  
175,000,000 YBN
245) Genetic comparison shows the most ancient flowering plant (Angiosperm)
still alive, "Amborella" evolving now.

This begins the "broad-leaf" plants.
There is only 1
species of Amborella still living.
Angiosperms (flowering plants) are the first plant
to produce fruits. A fruit is the ripened ovary, together with seeds, of a
flowering plant. In many species, the fruit incorporates the ripened ovary and
surrounding tissues. Fruits are the means by which flowering plants disseminate
seeds.
Class is "Palaeodicots"?



  
170,000,000 YBN
372) Carp, minnows, Piranhas evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
170,000,000 YBN
373) Salmon, Trout, Pike evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
165,000,000 YBN
247) Genetic comparison shows the second oldest line of Angiosperms, the Water
Lilies ("Nymphaeales") evolving now.

70 species.


  
150,000,000 YBN
374) Lightfish and Dragonfish evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
150,000,000 YBN
394) Oldest bird fossil, Archaeopteryx.
The Archaeopteryx fossil is from the Solnhofen
Limestone of the Upper Jurassic of Germany.

Archaeopteryx is a member of the extinct Subclass Archaeornithes.

There are many unsolved questions about birds. Did birds evolve flight from
trees or from the ground? From what part of the body did feathers evolve?
What colors were the first birds? Was Archaeopteryx warm blooded?

Biota
Domain Eukaryota - eukaryotes
Kingdom Animalia Linnaeus, 1758 - animals
Subkingdom
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
Branch Deuterostomia
Grobben, 1908 - deuterostomes
Infrakingdom Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
Phylum Chordata Bateson, 1885 - chordates

Subphylum Vertebrata Cuvier, 1812 - vertebrates
Infraphylum Gnathostomata
auct. - jawed vertebrates
Superclass Tetrapoda Goodrich, 1930 -
tetrapods
Series Amniota
Class Aves Linnaeus, 1758 -
birds
{Subclass †Archaeornithes}


  
150,000,000 YBN
395) Bird Confuciusornis fossil.

Unlike Archaeopteryx, Confuciusornis had no teeth.


Biota
Domain Eukaryota - eukaryotes
Kingdom Animalia Linnaeus, 1758 - animals
Subkingdom
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
Branch Deuterostomia
Grobben, 1908 - deuterostomes
Infrakingdom Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
Phylum Chordata Bateson, 1885 - chordates

Subphylum Vertebrata Cuvier, 1812 - vertebrates
Infraphylum Gnathostomata
auct. - jawed vertebrates
Superclass Tetrapoda Goodrich, 1930 -
tetrapods
Series Amniota
Class Aves Linnaeus, 1758 -
birds
{Subclass †Archaeornithes}



  
146,000,000 YBN
490) Multituberculata (extinct major branch of mammals) evolve.

Kingdom: Animalia
Class: Mammaliformes
Order: Multituberculata
Cope, 1884



  
145,000,000 YBN
415) Oldest flower fossil.
Oldest flower fossil, Archaefructus, in China, a
submerged wetland plant.




  
144,000,000 YBN
128) Start Cretaceous period (144-65 mybn), end Jurassic period (206-144 mybn).



  
140,000,000 YBN
457) Marsupials evolve.

Biota
Domain Eukaryota - eukaryotes
Kingdom Animalia Linnaeus, 1758 - animals
Subkingdom
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
Branch Deuterostomia
Grobben, 1908 - deuterostomes
Infrakingdom Chordonia (Haeckel, 1874)
Cavalier-Smith, 1998
Phylum Chordata Bateson, 1885 - chordates

Subphylum Vertebrata Cuvier, 1812 - vertebrates
Infraphylum Gnathostomata
auct. - jawed vertebrates
Superclass Tetrapoda Goodrich, 1930 -
tetrapods
Series Amniota
Mammaliaformes Rowe, 1988

Class Mammalia Linnaeus, 1758 - mammals

Subclass Theriiformes (Rowe, 1988) McKenna & Bell, 1997:vii,36

Infraclass Holotheria (Wible et al., 1995) McKenna & Bell, 1997:vii,43

Superlegion Trechnotheria McKenna, 1975

Legion Cladotheria McKenna, 1975
Sublegion
Zatheria McKenna, 1975
Infralegion
Tribosphenida (McKenna, 1975) McKenna & Bell, 1997:vii,48

Supercohort Theria (Parker & Haswell, 1897) McKenna & Bell, 1997:viii,49

Cohort Marsupialia (Illiger, 1811) McKenna & Bell,
1997:viii,51 - marsupials

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Marsupialia
Illiger, 1811
Orders
* Didelphimorphia
* Paucituberculata
* Microbiotheria
* Dasyuromorphia
* Peramelemorphia
* Notoryctemorphia
* Diprotodontia


  
140,000,000 YBN
458) Metornithes (early birds) evolve.




  
138,000,000 YBN
459) Ornithothoraces (early birds) evolve.




  
136,000,000 YBN
460) Enantiornithes (early birds) evolve.




  
134,000,000 YBN
461) Ornithurae (early birds) evolve.




  
132,000,000 YBN
462) Hesperornithiformes (early birds) evolve.




  
130,000,000 YBN
163) Amino acid sequence comparison shows the eutheria (placental mammals) line
separating from the marsupial line here at 130 mybn (first placental mammals).


  
130,000,000 YBN
375) Perch, Plaice, seahorses evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
130,000,000 YBN
376) Cod, hake, anglerfish evolve.

DOMAIN Eukaryota - eukaryotes
KINGDOM Animalia Linnaeus, 1758 - animals
SUBKINGDOM
Bilateria (Hatschek, 1888) Cavalier-Smith, 1983 - bilaterians
BRANCH Deuterostomia
Grobben, 1908 - deuterostomes
INFRAKINGDOM Chordonia (Haeckel, 1874) Cavalier-Smith,
1998
PHYLUM Chordata Bateson, 1885 - chordates
SUBPHYLUM Vertebrata
Cuvier, 1812 - vertebrates
INFRAPHYLUM Gnathostomata auct. - jawed
vertebrates
CLASS Osteichthyes Huxley, 1880
SUBCLASS
Actinopterygii - ray-finned fishes
INFRACLASS Cladistia

INFRACLASS Actinopteri
SUPERDIVISION Neopterygii
DIVISION
Halecostomi
SUBDIVISION Teleostei


  
128,000,000 YBN
248) Genetic comparison shows the Angiosperm "Austrobaileyales" evolving now.
100
species living.
A. scandens contains fruit, growing from its vines. The fruit is
apricot-coloured and contain tightly packed seeds in the shape of chestnuts.
The fruit is shaped in a similar fashion to that of a pear or eggplant. Fruit
from Austrobaileya has been known to grow to sizes of 7 cm in length by 5 cm.


  
128,000,000 YBN
249) Genetic comparison shows the Angiosperm "Chloranthaceae" evolving now.
70
living species.


  
128,000,000 YBN
250) Genetic comparison shows the Angiosperm group "Magnoliids" evolving now.
9,000
living species.
Includes magnolias, nutmeg, avocado, sassafras, cinnamin, black and
white pepper, camphor, bay (laurel) leaves.

Includes edible fruits: avocados (Persea
americana), guanabana, sour sop, chrimoya, and sweet sop. Spices: black and
white pepper (Piper nigrum), bay leaves (Laurus nigrus), nutmeg (Myristica
fragrans), cinnamon (Cinnamomum verum), and camphor (Cinnamomum caphora). In
addition to the ornamental flowers magnolias.
Class is "Palaeodicots"?

  
128,000,000 YBN
251) Genetic comparison shows the Angiosperm "Ceratophyllaceae" evolving now.
6
living species.
The oldest relative of all the eudicots.


  
128,000,000 YBN
252) Genetic comparison shows the Angiosperm group "Monocotyledons" (Monocots)
evolving now. Monocots are the second largest lineage of flowers after the
Eudicots, and include lilies, palms, orchids, and grasses.

Monocots are the second
largest lineage of flowers after the Eudicots (formally Dicotyledons) with
70,00
0 living species (20,000 species of orchids, and 15,000 species of grasses).
The two main
orders of Monocots are "Base Monocots" and "Commelinids".
All the grasses on earth come from
this line of flowers (check).

Base Monocots
(Family Petrosaviaceae)
Acorales
Alismatales
Asparagales (asparagus, onion, garlic, chives, agave, yucca,
aloe, hyacinth, orchids, iris, saffron)
Dioscoreales (yam)
Liliales (lillies)
Pandanales
Commelinids
(Family Dasypogonaceae)
Arecales (palms,date palm, rattan, coconut)
Commelinales
Poales (grasses: maize {corn},
rice, barley, oat, millet, wheat, rye, sorghum, sugarcane, bamboo, grass,
pineapple, water chestnut, papyrus {many alcohols, breads})
Zingiberales (cardamom,
tumeric, myoga, banana, ginger, arrowroot)



  
128,000,000 YBN
253) Genetic comparison shows the Angiosperm group Eudicots (includes most
former dicotyledons) evolving now. Eudicots are the largest lineage of
flowers.

eudicots are also called "tricolpates" which refers to the structure of the
pollen.
The two main groups are the "rosids" and "asterids".

* Basal eudicots
o Ranunculales
o
Buxales
o Trochodendrales
o Proteales
o Gunnerales
o Berberidopsidales
o Dilleniales
o
Caryophyllales
o Saxifragales
o Santalales
o Vitales
* Basal rosids
o Crossosomatales
o
Geraniales
o Myrtales
* Eurosids I
o Zygophyllales
o Celastrales
o Malpighiales
o
Oxalidales
o Fabales
o Rosales
o Cucurbitales
o Fagales
* Eurosids II
o
Brassicales
o Malvales
o Sapindales
* Basal asterids
o Cornales
o Ericales
* Euasterids I

o Garryales
o Solanales
o Gentianales
o Lamiales
o Unplaced:
Boraginaceae
* Euasterids II
o Aquifoliales
o Apiales
o Dipsacales
o Asterales


  
128,000,000 YBN
254) Genetic comparison shows the Angiosperm "Basal Eudicots" evolving now.
Includes
buttercup, clematis, poppies (opium and morphine), macadamia, lotus, sycamore.

ORDER
Ranunculales (buttercup, poppy, clematis)
ORDER Sabiaceae (*is not in wiki listing, but
is on s28 APG2)
ORDER Proteales (macadamia, sycamore, lotus)
ORDER Buxales
ORDER Trochodendrales
120mybn
cretaceous fossils

  
128,000,000 YBN
255) Genetic comparison shows the Angiosperm groups "Asterids" and "Rosids"
evolving and separating now.




  
128,000,000 YBN
256) Genetic comparison shows the Angiosperm "Basal Rosids" evolving now.
Includes
Geranium, Pomegranate, myrtle, clove, guava, feijoa, allspice, eucalyptus.
# Basal rosids
*
Crossosomatales
* Geraniales
* Myrtales


  
128,000,000 YBN
257) Genetic comparison shows the Angiosperm "Eurosids I" evolving now.
includes
coca, flax, willow, violet, mangosteen, coca (cocaine), poinsettia, rubber
tree, casava (manioc, yuca) {tapioca}, castor oil plant, Acerola ("Barbados
cherry"), willow, poplar, aspen, violet {pansy}, beans (green, lima, fava
{falafel}, kidney, pinto, navy, black, mung {sprouts}, popping), pea, peanut,
soybean, lentil, chick pea (garbonzo) {falafel}, lupin, clover, alfalfa
{sprouts}, cassia, jicama, tamarind, acacia, mesquite.


  
128,000,000 YBN
258) Genetic comparison shows the Angiosperm "Eurosids I" Order "Celastrales"
evolving now.

includes coca, flax, willow, violet, mangosteen, coca (cocaine),
poinsettia, rubber tree, casava (manioc, yuca) {tapioca}, castor oil plant,
Acerola ("Barbados cherry"), willow, poplar, aspen, violet {pansy}, beans
(green, lima, fava {falafel}, kidney, pinto, navy, black, mung {sprouts},
popping), pea, peanut, soybean, lentil, chick pea (garbonzo) {falafel}, lupin,
clover, alfalfa {sprouts}, cassia, jicama, tamarind, acacia, mesquite.


  
128,000,000 YBN
259) Genetic comparison shows the Angiosperm "Eurosids I" Order "Malpighiales"
evolving now.

includes gambooge, mangosteen, coca {cocaine, drink}, rubber tree,
cassava (manioc) {used like potato, tapioca}, castol oil, poinsettia, flax,
acerola (barbados cherry), willow, poplar, aspen, violet (pansy).

ORDER Malpighiales
37 FAMILIES
FAMILY
Clusiaceae (gambooge, mangosteen)
FAMILY Erythryloxaceae (coca)
FAMILY Euphorbiaceae (rubber
tree, cassava (manioc) {tapioca}, castor oil plant, poinsettia)
FAMILY Linaceae (flax)
FAMILY
Malpighiaceae (acerola (barbados cherry))
FAMILY Salicaceae (willow, poplar, aspen)
FAMILY
Violaceae (violet (pansy))

  
128,000,000 YBN
260) Genetic comparison shows the Angiosperm, "Eurosids I" Order "Oxalidales"
evolving now.

includes Cephalotus Follicularis (fly-cather plant), wood sorrel
family (leaves show "sleep movements"), oca (edible tuber)


  
128,000,000 YBN
261) Genetic comparison shows the Angiosperm, "Eurosids I" Order "Fabales"
evolving now.

includes beans (green, lima, kidney, pinto, navy, black, mung
{sprouts}, fava {falafel}, cow (black-eyed), popping), pea, peanut, soy {tofu,
miso, tempeh, milk}, lentil, chick pea (garbonzo) {falafel}, lupin, clover,
alfalfa {sprouts}, cassia, jicama, Judas tree, tamarind, acacia, mesquite,
Judas tree

ORDER Fabales
4 Families
FAMILY Fabaceae (legumes)
3 Subfamilies
SUBFAMILY Faboideae (beans (green,
lima, kidney, pinto, navy, black, mung, fava, cow (black-eyed), popping), peas,
peanuts, soybeans, lentils, chick pea (garbanzo), jicama, lupins, clover,
alfalfa, kudzu)
SUBFAMILY Caesalpinioideae (brazilwood, palo verde, honey locust,
Judas-tree, Mopane, Coralwood, Hymenaea, Tamarind)
SUBFAMILY Mimosoideae (acacia,
anadenanthera, leucaena, mimosa {sensitive plant}, mesquite)

  
128,000,000 YBN
262) Genetic comparison shows the Angiosperm, "Eurosids I" Order "Rosales"
evolving now.

includes hemp (cannibis, marijuana) {rope, oil, recreational drug},
hackberry, hop {beer}, breadfruit, cempedak, jackfruit, marang, paper mulberry,
fig, banyan, strawberry, rose, red raspberry, black raspberry, blackberry,
cloudberry, loganberry, salmonberry, thimbleberry, serviceberry, chokeberry,
quince, loquat, apple, crabapple, pair, plums, cherries, peaches, apricots,
almonds, jujube, elm

ORDER Rosales
9 Families
FAMILY Barbeyaceae
FAMILY Cannabaceae (hemp family: cannibis,
hackberry, hop)
FAMILY Dirachmaceae
FAMILY Elaeagnaceae
FAMILY Moraceae (mulberry family: breadfruit,
cempedak, jackfruit, marang, paper mulberry, fig )
FAMILY Rosaceae (rose family)

SUBFAMILY Rosoideae (strawberry, rose, red raspberry, black raspberry,
blackberry, cloudberry, loganberry, salmonberry, dewberry, thimbleberry)
SUBFAMILY
Spiraeoideae (serviceberry, chokeberry, quince, loquat, apple, crabapple,
medlar, pair)
SUBFAMILY Maloideae
SUBFAMILY Amygdaloideae or Prunoideae (plums, cherries,
peaches, apricots, almonds)
FAMILY Rhamnaceae (buckthorn family: jujube)
FAMILY Ulmaceae (elm
family: elm)
FAMILY Urticaceae (nettle family)

  
128,000,000 YBN
263) Genetic comparison shows the Angiosperm, "Eurosids I" Order "Cucurbitales"
evolving now.

includes watermelon, musk, cantaloupe, honeydew, casaba, cucumbers,
gourds, pumpkins, squashes (acorn, buttercup, butternut, cushaw, hubbard,
pattypan, spaghetti), zucchini, begonia

ORDER Cucurbitales
1600 species in seven families. The
largest families are Begoniaceae with 920 species and Cucurbitaceae with 640
species.
FAMILY Cucurbitaceae (gourd family: watermelon, musk, cantaloupe, honeydew,
casaba, cucumber {pickles}, gourds, pumpkins, squashes (acorn, buttercup,
butternut, cushaw, hubbard, pattypan, spaghetti), zucchini)
FAMILY Begoniaceae (begonia
family: begonia)
FAMILY Datiscaceae
FAMILY Tetramelaceae
FAMILY Corynocarpaceae
FAMILY Coriariaceae
FAMILY Anisophylleaceae

  
128,000,000 YBN
264) Genetic comparison shows the Angiosperm, "Eurosids I" Order "Fagales"
evolving now.

includes Birch, Hazel {nut}, Filbert {nut}, Chestnut, Beech {nut},
Oak {nut, cork}, walnut, pecan, hickory, bayberry

ORDER Fagales
FAMILY Betulaceae - Birch
family (Birch, Hornbeam, Hazel {nut}, Filbert {nut})
FAMILY Casuarinaceae - She-oak
family
FAMILY Fagaceae - Beech family (Chestnut, Beech {nut}, Oak {nut}, cork,
flooring)
FAMILY Juglandaceae - Walnut family (walnut, pecan, hickory {nut})
FAMILY
Myricaceae - Bayberry family (Bayberry {wax, food})
FAMILY Nothofagaceae - Southern
beech family
FAMILY Rhoipteleaceae - Rhoiptelea family
FAMILY Ticodendraceae -
Ticodendron family

  
128,000,000 YBN
265) Genetic comparison shows the Angiosperm "Monocotyledon" (Monocot) group
"Base Monocots" evolving now.

ORDER Acorales
ORDER Alismatales
ORDER Asparagales (asparagus, onion,
garlic, chives, agave, yucca, aloe, hyacinth, orchids, iris)
ORDER Dioscoreales
(yam)
ORDER Liliales (lily)
ORDER Pandanales

* Family Petrosaviaceae

The APG II classification of the Asparagales is as follows:

* Alliaceae (onion family: chive, garlic, onion)
o Agapanthaceae
o
Amaryllidaceae (amaryllis family)
* Asparagaceae (asparagus family)
o Agavaceae
(agave family: agave, yucca)
o Aphyllanthaceae
o Hesperocallidaceae
o Hyacinthaceae
(hyacinth family: bluebell, hyacinth)
o Laxmanniaceae
o Ruscaceae
o Themidaceae
*
Asteliaceae
* Blandfordiaceae
* Boryaceae
* Doryanthaceae
* Hypoxidaceae
* Iridaceae (iris family)
* Ixioliriaceae
* Lanariaceae
* Orchidaceae
(orchid family)
* Tecophilaeaceae
* Xanthorrhoeaceae
o Asphodelaceae (asphodel family: aloe, asphdel)

o Hemerocallidaceae

  
128,000,000 YBN
266) Genetic comparison shows the Angiosperm "Monocotyledon" (Monocot) group
"Commelinids" evolving now.

Commelinids
Arecales (palms,date palm, rattan, coconut)
Commelinales
Poales (grasses: maize {corn}, rice,
barley, oat, millet, wheat, rye, sorghum, sugarcane, bamboo, grass, pineapple,
water chestnut, papyrus {many alcohols, breads})
Zingiberales (cardamom, tumeric,
myoga, banana, ginger, arrowroot)
(Family Dasypogonaceae) (new order?)



  
128,000,000 YBN
267) Genetic comparison shows the Angiosperm "Core Eudicots" evolving now.
Includes
carnation, cactus, caper, buckwheat, rhubarb, sundew, venus flytrap, pitcher
plants {old world}, beet, quinoa, spinach, currant, sweet gum, peony,
with-hazel, mistletoe, grape.

ORDER Gunnerales
ORDER Berberidopsidales
ORDER Aextoxicaceae
ORDER Dilleniales
ORDER
Caryophyllales (carnation, beet, spinach, quinoa, cactus {prickly pear,
peyote/mescaline}, caper, buckwheat, rhubarb, sundew, venus flytrap, pitcher
plants {old world})
ORDER Saxifragales (gooseberry, sweet gum, currants, peony,
witch-hazel)
ORDER Santalales (sandalwood, mistletoe)
ORDER Vitales (grape {wine, juice, jelly, raisen,
oil, dolma})


  
128,000,000 YBN
268) Genetic comparison shows the Angiosperm "Eurosids I" Order "Zygophyllales"
evolving now.

includes
ORDER Zygophyllales (is not on s28 APG2)
FAMILY Zygophyllaceae
FAMILY Krameriaceae

  
128,000,000 YBN
269) Genetic comparison shows the Angiosperm "Eurosids II" evolving now.
includes
Eurosids II
ORDER Brassicales
ORDER Malvales
ORDER Sapindales

  
128,000,000 YBN
270) Genetic comparison shows the Angiosperm "Eurosids II" Order "Brassicales"
evolving now.

includes horseradish, rapeseed, mustard {plain, brown, black, indian,
sarepta, asian}, rutabaga, kale, Chinese broccoli (kai-lan), cauliflower,
collard greens, cabbage (white and red {coleslaw, sauerkraut}), kohlrabi,
broccoli, watercress, radish, wasabi, mignonette, papaya

mignonette, mallows, soapberry, citris, mahogany, cashew, frankincense, cacao
(chocolate), cola {kola nuts, caffeine}

Eurosids II
ORDER Brassicales (horseradish,
rapeseed, mustard {plain, brown, black, indian, sarepta, asian}, rutagbaga,
kale, Chinese broccoli, cauliflower, collard greens, cabbage (white and red)
{coleslaw, sauerkraut}, kohlrabi, broccoli, watercress, radish, wasabi,
mignonette, papaya)
ORDER Malvales
ORDER Sapindales

  
128,000,000 YBN
271) Genetic comparison shows the Angiosperm "Eurosids II" Order "Malvales"
evolving now.

includes okra, marsh mallow, kola nut, cotton, hibiscus, balsa, cacao
{chocolate}, soapberry, citris, mahogany, cashew, frankincense

Eurosids II
ORDER Brassicales
(horseradish, rapeseed, mustard {plain, brown, black, indian, sarepta, asian},
rutagbaga, kale, Chinese broccoli, cauliflower, collard greens, cabbage (white
and red) {coleslaw, sauerkraut}, kohlrabi, broccoli, watercress, radish,
wasabi, mignonette, papaya)
ORDER Malvales (okra, marsh mallow, kola nut, cotton,
hibiscus, balsa, cacao {chocolate})
ORDER Sapindales

  
128,000,000 YBN
272) Genetic comparison shows the Angiosperm "Eurosids II" Order "Sapindales"
evolving now.

includes maple, buckeye, horse chestnut, longan, lychee, rambutan,
guarana, bael, orange, lemon, grapefruit, lime, tangerine, pomelo, kumquat,
langsat, duku, mahogany, cashew, mango, pistachio, sumac, peppertree,
poison-ivy, frankincense

Eurosids II
ORDER Brassicales (horseradish, rapeseed, mustard {plain,
brown, black, indian, sarepta, asian}, rutagbaga, kale, Chinese broccoli,
cauliflower, collard greens, cabbage (white and red) {coleslaw, sauerkraut},
kohlrabi, broccoli, watercress, radish, wasabi, mignonette, papaya)
ORDER Malvales
(okra, marsh mallow, kola nut, cotton, hibiscus, balsa, cacao {chocolate})
ORDER Sapindales
(maple, buckeye, horse chestnut, longan, lychee, rambutan, guarana, bael,
orange, lemon, grapefruit, lime, tangerine, pomelo, kumquat, langsat, duku,
mahogany cashew, mango, pistachio, sumac, peppertree, poison-ivy, frankincense

  
128,000,000 YBN
273) Genetic comparison shows the Angiosperm "Basal Asterids" evolving now.


  
128,000,000 YBN
274) Genetic comparison shows the Angiosperm "Basal Asterids" Order "Cornales"
evolving now.

Includes dogwoods, tupelos, dove tree
# Basal asterids

* Cornales (dogwoods, tupelo, dove tree)
* Ericales

  
128,000,000 YBN
275) Genetic comparison shows the Angiosperm "Basal Asterids" Order "Ericales"
evolving now.

Includes kiwifruit (kiwi), Impatiens, ebony, persimmon, heather,
crowberry, rhododendrons, azalias, cranberries, blueberries, lingonberry,
bilberry, huckleberry, brazil nut, primrose, sapodilla, mamey sapote (sapota),
chicle, balatá, canistel, pitcher plants {carniverous}, tea {Camellia
sinensis}

# Basal asterids

* Cornales (dogwoods, tupelo, dove tree)
* Ericales (kiwifruit, Impatiens,
ebony, persimmon, heather, crowberry, rhododendrons, azaleas, cranberry,
blueberry, lingonberry, bilberry, huckleberry, brazil nut, primrose,
sapodilla, mamey sapote (sapota), chicle, balatá, canistel, pitcher plants
{carniverous, genus Sarracenia}, tea)

  
128,000,000 YBN
276) Genetic comparison shows the Angiosperm "Euasterids I" evolving now.


  
128,000,000 YBN
277) Genetic comparison shows the Angiosperm "Euasterids I" order "Garryales"
evolving now.

includes
# Euasterids I

ORDER Garryales
ORDER Solanales
ORDER Gentianales
ORDER Lamiales
ORDER Unplaced: Boraginaceae

  
128,000,000 YBN
278) Genetic comparison shows the Angiosperm "Euasterids I" order "Solanales"
evolving now.

includes deadly nightshade or belladonna, capsicum (bell pepper,
paprika, Jalapeño, Pimento), cayenne pepper, datura, tomatos, mandrake,
tobacco, petunia, tomatillo, potato, eggplant, morning glory, sweet potato,
water spinach

# Euasterids I

ORDER Garryales
ORDER Solanales (deadly nightshade or belladonna, capsicum {bell pepper,
paprika, Jalapeño, Pimento}, cayenne pepper, datura, tomatos, mandrake,
tobacco, petunia, tomatillo, potato, eggplant, morning glory, sweet potato,
water spinach)
ORDER Gentianales
ORDER Lamiales
ORDER Unplaced: Boraginaceae

  
128,000,000 YBN
279) Genetic comparison shows the Angiosperm "Euasterids I" order "Gentianales"
evolving now.

includes gentian, dogbane, carissa (Natal plum), oleander, logania,
coffee

# Euasterids I

ORDER Garryales
ORDER Solanales (deadly nightshade or belladonna, capsicum {bell pepper,
paprika, Jalapeño, Pimento}, cayenne pepper, datura, tomatos, mandrake,
tobacco, petunia, tomatillo, potato, eggplant, morning glory, sweet potato,
water spinach)
ORDER Gentianales (gentian, dogbane, carissa (Natal plum), oleander,
logania, coffee)
ORDER Lamiales
ORDER Unplaced: Boraginaceae

  
128,000,000 YBN
280) Genetic comparison shows the Angiosperm "Euasterids I" order "Lamiales"
evolving now.

includes lavender, mint, peppermint, basil, marjoram, oregano,
perilla, rosemary, sage, savory, thyme, teak, sesame, corkscrew plants,
bladderwort, snapdragon, olive, ash, lilac, jasmine

# Euasterids I

ORDER Garryales
ORDER Solanales (deadly nightshade or belladonna, capsicum {bell pepper,
paprika, Jalapeño, Pimento}, cayenne pepper, datura, tomatos, mandrake,
tobacco, petunia, tomatillo, potato, eggplant, morning glory, sweet potato,
water spinach)
ORDER Gentianales (gentian, dogbane, carissa (Natal plum), oleander,
logania, coffee)
ORDER Lamiales (lavender, mint, peppermint, basil, marjoram, oregano,
perilla, rosemary, sage, savory, thyme, teak, sesame, corkscrew plants,
bladderwort, snapdragon, olive, ash, lilac, jasmine)
ORDER Unplaced: Boraginaceae

  
128,000,000 YBN
281) Genetic comparison shows the Angiosperm "Euasterids I" (unplaced) family
"Boraginaceae" evolving now.

includes forget-me-not
# Euasterids I

ORDER Garryales
ORDER Solanales (deadly nightshade or belladonna, capsicum {bell pepper,
paprika, Jalapeño, Pimento}, cayenne pepper, datura, tomatos, mandrake,
tobacco, petunia, tomatillo, potato, eggplant, morning glory, sweet potato,
water spinach)
ORDER Gentianales (gentian, dogbane, carissa (Natal plum), oleander,
logania, coffee)
ORDER Lamiales (lavender, mint, peppermint, basil, marjoram, oregano,
perilla, rosemary, sage, savory, thyme, teak, sesame, corkscrew plants,
bladderwort, snapdragon, olive, ash, lilac, jasmine)
ORDER Unplaced: Boraginaceae
(forget-me-not)

  
128,000,000 YBN
282) Genetic comparison shows the Angiosperm "Euasterids II" order
"Aquifoliales" evolving now.

includes holly
# Euasterids II

ORDER Aquifoliales (hollies)
ORDER Apiales
ORDER Dipsacales
ORDER Asterales

  
128,000,000 YBN
283) Genetic comparison shows the Angiosperm "Euasterids II" order "Apiales"
evolving now.

includes dill, angelica, chervil, celery, caraway, cumin, sea holly,
poison hemlock, coriander (cilantro), carrot, lovage, parsnip, anise, fennel,
cicely, parsley, ivy, ginseng

# Euasterids II

ORDER Aquifoliales (hollies)
ORDER Apiales (dill, chervil, angelica, celery, caraway,
poison hemlock, coriander {cilantro}, cumin, carrot, sea holly, fennel, cicely,
parsnip, parsley, anise, lovage, ginseng, ivy)
ORDER Dipsacales
ORDER Asterales

  
128,000,000 YBN
284) Genetic comparison shows the Angiosperm "Euasterids II" order "Dipsacales"
evolving now.

includes Elderberry, Honeysuckle, Teasel, Corn Salad
# Euasterids II

ORDER Aquifoliales (hollies)
ORDER Apiales (dill, chervil, angelica, celery, caraway,
poison hemlock, coriander {cilantro}, cumin, carrot, sea holly, fennel, cicely,
parsnip, parsley, anise, lovage, ginseng, ivy)
ORDER Dipsacales (Elderberry,
Honeysuckle, Teasel, Corn Salad)
ORDER Asterales

  
128,000,000 YBN
285) Genetic comparison shows the Angiosperm "Euasterids II" order "Asterales"
evolving now.

includes burdock, tarragon, daisy, marigold, Safflower, chrysanthemum
(mum), chickory, endive, artichoke, Sunflower, sunroot (Jerusalem artichoke),
lettuce, chamomile, black-eyed susan, black salsify, dandelion, zinnia

# Euasterids
II

ORDER Aquifoliales (hollies)
ORDER Apiales (dill, chervil, angelica, celery, caraway,
poison hemlock, coriander {cilantro}, cumin, carrot, sea holly, fennel, cicely,
parsnip, parsley, anise, lovage, ginseng, ivy)
ORDER Dipsacales (Elderberry,
Honeysuckle, Teasel, Corn Salad)
ORDER Asterales (Burdock, tarragon, daisy, marigold,
Safflower, chrysanthemum {mum}, chickory, endive, artichoke, sunflower, sunroot
(Jerusalem artichoke), lettuce, chamomile, black-eyed susan, black salsify,
dandelion, zinnia

  
120,000,000 YBN
463) Neornithes (modern birds) evolve.
More important anatomical characteristics
include horn beak; teeth absent; fused limb bones. In addition Neornithes have
a fully-separated four-chambered heart and typically exhibit complex social
behaviors.




  
112,000,000 YBN
481) Steropodon galmani, an extinct monotreme, the earliest platypus-like
species, lives.


Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Monotremata
Family: Steropodontidae
Genus: Steropodon
Species: S. galmani
Binomial name
Steropodon
galmani
Archer, Flannery, Ritchie, & Molnar, 1985



  
110,000,000 YBN
416) Sauroposiedon, a long-neck brachiosaur (sauropod) fossil.
Sauroposiedon
fossil, a long-neck (sauropod) brachiosaur from Oklahoma, possibly the tallest
animal of all time, at an estimated height of 60 feet.




  
105,000,000 YBN
417) Argentinosaurus, a long-neck titanosaur (sauropod) fossil.
Argentinosaurus
, a long-neck (sauropod) titanosaur from South America, possibly the longest
animal of all time, at an estimated 130 to 140 feet length.




  
105,000,000 YBN
491) Afrotheres (elephants, manatees, aardvarks) evolve.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass: Eutheria (Huxley, 1880)
Superorder
Afrotheria:


  
100,000,000 YBN
164) Amino acid sequence comparison shows the mammal line separating from the
primate line here at 100 mybn (first primates).


  
100,000,000 YBN
418) Carnotaurus fossil, a horned, meat-eating (theropod) dinosaur from South
America.

Carnotaurus fossil, a horned, meat-eating (theropod) dinosaur from
South America. The fossil includes skin impressions of its face.




  
100,000,000 YBN
464) Tinamiformes (modern birds) evolve.
More important anatomical characteristics
include horn beak; teeth absent; fused limb bones. In addition Neornithes have
a fully-separated four-chambered heart and typically exhibit complex social
behaviors.




  
100,000,000 YBN
465) Ratites (ostrich, emu, cassowary, kiwis) evolve.




  
100,000,000 YBN
480) Kollikodon ritchiei, an extinct monotreme lives.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Monotremata
Family: Kollikodontidae
Genus: Kollikodon
Species: K. ritchiei
Binomial name
Kollikodon
ritchiei
Flannery, Archer, Rich & Jones, 1995



  
95,000,000 YBN
419) Spinosaurus fossil, perhaps the largest meat-eating dinosaur, estimated to
have been 45 to 50 feet long.

Spinosaurus fossil, perhaps the largest
meat-eating dinosaur, estimated to have been 45 to 50 feet long. The only
skeleton ever found was destroyed during World War 2.




  
95,000,000 YBN
498) Xenarthrans (Sloths, Anteaters, Armadillos) evolve.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass Edentata:
Superorder Xenarthra:


  
85,000,000 YBN
466) Galliformes (Chicken, Duck, Goose, Turkey, Pheasants, Peacocks, Quail)
evolve.





  
85,000,000 YBN
467) Anseriformes (water birds) evolve.




  
85,000,000 YBN
499) Laurasuatheres evolve. This is a major line of mammals that include:
bats, camels, pigs, deer, sheep, hippos, whales, horses, rhinos, cats, dogs,
bears, seals, walrus).


Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder: Euarchontoglires


  
84,000,000 YBN
454) Laramide (Rocky) mountains form.




  
82,000,000 YBN
420) Hadrosaurs, duck-billed dinosaurs are common.
Duck-billed dinosaurs
(hadrosaurs) were common like Corythyosaurus , Edmontosaurus , Lambeosaurus ,
Maiasaurus , and Parasaurolophus . Maiasaurs are examples of dinosaurs from
which fossil nests, eggs, and baby dinosaurs have been found.




  
82,000,000 YBN
500) Shrews, moles, hedgehogs (Laurasuatheres) evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
80,000,000 YBN
421) Protoceratops, an early shield-headed (ceratopsian) dinosaur fossil.
Proto
ceratops, an early shield-headed (ceratopsian) dinosaur fossil. It was the
first dinosaur discovered with fossil eggs. These eggs and nests were found in
Mongolia in the 1920's.




  
80,000,000 YBN
422) Raptor (dromaeosaur) fossils.
Raptors (dromaeosaurs) are Cretaceous
dinosaurs, which had large, hook claws on their feet. Velociraptor is one
example. The most famous Velociraptor is a skeleton preserved in combat with a
Protoceratops from Mongolia, China .




  
80,000,000 YBN
482) American and true opossums (American Marsupials) evolve.
This is the
Marsupial Order Didelphimorphia.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Marsupialia
Order: Didelphimorphia
Gill, 1872
Family:
Didelphidae
Gray, 1821



  
80,000,000 YBN
501) Bats (Laurasuatheres) evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
78,000,000 YBN
502) Camels, Pigs, Deer, Sheep, Hippos, Whales (Laurasuatheres) evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
77,000,000 YBN
483) Shrew opossums (American Marsupials) evolve.
This is the Marsupial Order
Paucituberculata. 6 surviving species confined to Andes mountains in South
America.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Marsupialia
Order: Paucituberculata
Ameghino, 1894
Family:
Caenolestidae
Trouessart, 1898



  
76,000,000 YBN
503) Horses, Tapirs, Rhinos (Laurasuatheres) evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
75,000,000 YBN
204) Oldest fossil of testate amoeba from Grand Canyon, USA.


  
75,000,000 YBN
423) Ceratopsian (shield-headed) dinosaurs are common.
Ceratopsian
(shield-headed) dinosaurs were common in the late Cretaceous. Examples are
Monoclonius , and Styrakosaurus . Triceratops, which lived at the end of
Cretaceous, was the largest of its kind, reaching 30 feet in length.




  
75,000,000 YBN
492) Aardvark (Afrotheres) evolves.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass: Eutheria (Huxley, 1880)
Superorder
Afrotheria:


  
75,000,000 YBN
504) Cats, Dogs, Bears, Weasels, Hyenas, Seals, Walruses (Laurasuatheres)
evolve.


Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
75,000,000 YBN
505) Pangolins (Laurasuatheres) evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Laurasiatheria


  
75,000,000 YBN
506) Euarchontoglires evolve. This is a major line of mammals that includes
rats, squirrels, rabbits, lemurs, monkeys, apes, and humans.


Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Euarchontoglires


  
73,000,000 YBN
484) Bandicoots and Bilbies (Australian Marsupials) evolve.
This is the
Marsupial Order Peramelemorphia.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass:
Marsupialia
Order: Peramelemorphia
Ameghino, 1889



  
70,000,000 YBN
424) Two of the largest meat-eating dinosaurs of all time exist. Tyrannosaurus
rex is the top predator in North America and Giganotosaurus is in South
America.





  
70,000,000 YBN
425) Ankylosaurs (shield back and/or club tails) evolve.
The armored
ankylosaurs (had a shield back or clubbed tail) was the most heavily armored
land-animals in the history of earth. These plant-eating were low to the
ground for optimal protection. Many had spikes that stuck out from their
bone-covered back. Ankylosaurus even had bony plates on its eyelids.




  
70,000,000 YBN
426) Mososaurs, sea serpents evolve.




  
70,000,000 YBN
493) Tenrecs and golden moles (Afrotheres) evolve.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass: Eutheria (Huxley, 1880)
Superorder
Afrotheria:


  
70,000,000 YBN
494) Elephant Shrews (Afrotheres) evolve.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass: Eutheria (Huxley, 1880)
Superorder
Afrotheria:


  
70,000,000 YBN
507) The ancestor of all rabbits, hares and pikas evolve.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Euarchontoglires


  
70,000,000 YBN
516) The ancestor of Tree Shrews and Colugos evolves.

Kingdom: Animalia
Class: Mammalia
Subclass: Eutheria
Superorder Euarchontoglires
Order: Dermoptera (Illiger, 1811)
Family:
Cynocephalidae (Simpson, 1945)


  
70,000,000 YBN
1383) The giant bird-like dinosaur Gigantoraptor erlianensis lives now.
  
65,500,000 YBN
397) End of Cretaceous mass extinction event happens.
Dino