History of Life 1
Tucson Botanical Gardens
Brian O’Meara
EEB464 Fall 2012
History of Life 1
Tucson Botanical Gardens
Brian O’Meara
EEB464 Fall 2012
Big Bang 13.73 BYA
First stars produce more complex
elements, then (some) explode
Solar system (sun, planets) form
4.6 BYA
Moon broken off from Earth,
4.53 BYA
Moon broken off from Earth,
4.53 BYA
Ow!
Heavy bombardment,
4.1 - 3.8 BYA
actually, Mimas, a moon of saturn
Heavy bombardment,
4.1 - 3.8 BYA
actually, Mimas, a moon of saturn
Life evolves
~3.8 BYA
stromatolite fossil and living organisms
Photosynthesis evolves
somewhere 3.5 - 2.8 BYA
H
O
O
H
C
+
O
= Sugar +
O
O
Great oxidation event
2.45 - 2.22 BYA
H
O
O
H
C
+
O
= Sugar +
O
O
Huronian glaciation
3.2 - 2.4 BYA
Andree Valley
a long time passes
What are archaea, eukaryotes
a long time passes
Andree Valley
Archaea+Eukaryotes and Eubacteria diverge
What are archaea, eukaryotes
a long time passes
Andree Valley
Archaea+Eukaryotes and Eubacteria diverge
Eukaryotes diverge from Archaea
What are archaea, eukaryotes
a long time passes
Andree Valley
Archaea+Eukaryotes and Eubacteria diverge
Eukaryotes diverge from Archaea
Life is still single-celled
What are archaea, eukaryotes
a long time passes
Andree Valley
Archaea+Eukaryotes and Eubacteria diverge
Eukaryotes diverge from Archaea
Life is still single-celled
What are archaea, eukaryotes
Today, Bacteria (which I sometimes call Eubacteria) and Archaea. Note that they used to be
called “prokaryotes” but that’s not a clade
Bacteria
Archaea
Eukarya
Circular chromosome
Y
Y
N
Histones with DNA
N
Y
Y
Flagella
Spinning
Spinning
Waving
Unicellular
Y
Y
Varies
Organelles
~N
N
Y
Some key traits
http://www.youtube.com/watch?v=9w421z4fsOU
a long time passes
Andree Valley
Archaea+Eukaryotes and Eubacteria diverge
Eukaryotes diverge from Archaea
Life is still single-celled
What are archaea, eukaryotes
Ediacaran fauna
0.63 BYA = 630 MYA
Wikimedia
commons
Cambrian
542 MYA
John Sibbick
Hard skeletons
Wikimedia
commons
Permian-Triassic extinction
251 MYA
Permian-Triassic extinction
251 MYA
Permian-Triassic extinction
251 MYA
Dinosaurs evolved after this.
KT (Cretaceous-Tertiary) extinction
65.5 MYA
Brian Franczak
Wiped out ammonites as well as non-avian dinos
Sun eventually becomes red giant,
expands
Franck et al. Causes and timing of future biosphere extinctions. Biogeosciences (2006) vol. 3 (1) pp. 85-92
Schröder and Smith. Distant future of the Sun and Earth revisited. Monthly Notices of the Royal Astronomical Society (2008) vol. 386 (1) pp. 155-163
Sun eventually becomes red giant,
expands
Franck et al. Causes and timing of future biosphere extinctions. Biogeosciences (2006) vol. 3 (1) pp. 85-92
Schröder and Smith. Distant future of the Sun and Earth revisited. Monthly Notices of the Royal Astronomical Society (2008) vol. 386 (1) pp. 155-163
ex
tin
ar
ity
-1
es
go
fe
Li
-2
N
el
tic
ul
M
-3
O
W
lu
l
ve
s
ev
ol
fe
Li
-4
ct
Sun eventually becomes red giant,
expands
0
1
Franck et al. Causes and timing of future biosphere extinctions. Biogeosciences (2006) vol. 3 (1) pp. 85-92
Schröder and Smith. Distant future of the Sun and Earth revisited. Monthly Notices of the Royal Astronomical Society (2008) vol. 386 (1) pp. 155-163
Discussion: how might a major
extinction like the one at the end of
the Permian affect life?
Discussion: how might a major
extinction like the one at the end of
the Permian affect life?