Early Divergence Events

1
Early Divergence Events

• Dan Graur

2
THE UNIVERSAL PHYLOGENY The first divergence
events
3
All the organic beings which have ever lived on
this earth have descended from one primordial
form, into which life was first breathed.
Charles Darwin (1859)
4
Lynn Margulis
5
Extremophiles thermophiles hyperthermophiles ps
ychrophiles halophiles, acidophiles alkaliphiles
6
George Fox University of Houston
Carl Woese University of Illinois at
Urbana-Champaign
Woese C, Fox G. 1977. Phylogenetic structure of
the prokaryotic domain the primary kingdoms.
Proc. Natl. Acad. Sci. USA 74 50885090.
7
(No Transcript)
8
muramic acid
Archaea Bacteria Eukarya Histones
- Muramic acid in cell walls -
- Formylmethionine -
- Sensitivity to
diphtheria toxin -
Sensitivity to
chloramphenicol, streptomycin and kanamycin
-
- Growth at gt80C
- Membrane lipids ether-linked
ester-linked ester-linked
9
(No Transcript)
10
Where is the root?
11
(No Transcript)
12
Phylogenetic tree for the elongation-factor
genes, EF-Tu and EF-G.
13
Superkingdom Metakaryota Animalia Plantae
Fungi
14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
Mereschkowsky CV. 1905. Über Natur und Ursprung
der Chromatophoren im Pflanzenreiche On the
nature and origin of chromatophores in the plant
kingdom. Biologisches Zentralblatt 25593604.
Constantin V. Mereschkowsky (1855-1921)
26
(No Transcript)
27
Prochloron (a cyanobacterium)
28
Rickettsia a-proteobacteria
29
(No Transcript)
30
(No Transcript)
31
(No Transcript)
32

• rRNA tree.
• (b) Introns-early tree.
• (c) Neomuran tree.
• (d) Symbiotic tree.
• (e) Prokaryote-host tree.

33
The Archezoa HypothesisT. Cavalier-Smith (1983)

• Archezoa are eukaryotes which primitively lack
  mitochondria
• The nucleus was invented before the mitochondrion
  was acquired
• The first eukaryotes were anaerobes

34
The Archezoa hypothesis
Mitochondria
Prokaryotic outgroup
35
Amitochondriate protists
Giardia lamblia
Trichomonas vaginalis
36
Amitochondriate protists
37
(No Transcript)