1. The History of Life on Earth, Origin of Life, Procaryotes
Chapter 25, 27
The History of Life on Earth, Origin of Life, Procaryotes
February 11, 2011
For origin and early life see

2. The History of Life on Earth: Chapter 25

3. eukaryotes both are prokaryotic EUKARYA BACTERIA ARCHAEA Land plants
Dinoflagellates
Green algae
Forams
Ciliates
Diatoms
Red algae
Amoebas
Cellular slime molds
Euglena
Trypanosomes
Animals
Leishmania
Fungi
Sulfolobus
Green nonsulfur bacteria
Thermophiles
(Mitochondrion)
Figure The three domains of life, supported by the sequence from many sequenced genomes
Spirochetes
Halophiles
Chlamydia
COMMON
ANCESTOR
OF ALL
LIFE
Green
sulfur bacteria
BACTERIA
Methanobacterium
Cyanobacteria
both are prokaryotic
ARCHAEA
(Plastids, including
chloroplasts)

4. From Two Kingdoms to Three Domains
Recently, based on phylogenetic analysis: the three domain system has been adopted: the domains are Bacteria, Archaea, and Eukarya.
So how did it all start, how long ago did it start, and then what happened?

5. The First Single-Celled Organisms
The oldest known fossils are stromatolites, rock-like structures composed of many layers of bacteria and sediment
Stromatolites date back 3.5 billion years ago
Prokaryotes were Earth’s sole inhabitants from 3.5 to about 2.1 billion years ago

6. Fig. 25-4i
Figure 25.4 Documenting the history of life
Stromatolites

7. Fossilized stromatolite
Fig. 25-4j
Figure 25.4 Documenting the history of life
Fossilized stromatolite

8. The oldest fossils, from the Australian rocks called the Apex Chert:
And the Gunflint Chert, 1.9 billion yr old. From north of Lake Superior
3.5 billion yr old

9. Meteorite contents witness ancient non-biological organic molecules

10. including molecules that form osmotically functional vesicles
Nonanoic acid
On polycyclic aromatic hydrocarbons:
Deamer (1999) extracted the water-soluble portion of a carbonaceous chhhondrite (meteorite) and yielded the bilayer membrane vesicles at the top, which are um in diam and are a micture of the two molcule types pictured. The bilayer is resistant to ion flux.
Deamer: amphiphilic compounds capable of membrane formation are present in carbonaceous meteorites and are able to self-assemble into bilayer membranes. … the observation that membranes can self-assemble from the amphiphilic components at least makes it more plausible that membrane-bounded structures were present at the time of life's origin.
Polycyclic aromatic hydrocarbons

11. (a) Simple reproduction by liposomes Maltose (b) Simple metabolism
Fig. 25-3
20 µm
Glucose-phosphate
Glucose-phosphate
Phosphatase
Starch
Amylase
Phosphate
Maltose
Figure 25.3 Laboratory versions of protobionts
(a) Simple reproduction by
liposomes
Maltose
(b) Simple metabolism

12. Ceno- zoic Meso- zoic Humans Paleozoic Colonization of land Animals
Fig. 25-7
Ceno-
zoic
Meso-
zoic
Humans
Paleozoic
Colonization
of land
Animals
Origin of solar
system and
Earth 1 4
Proterozoic
Archaean
Prokaryotes
Figure 25.7 Clock analogy for some key events in Earth’s history
Billions of
years ago 2 3
Multicellular
eukaryotes
Single-celled
eukaryotes
Atmospheric
oxygen

13. eukaryotes both are prokaryotic EUKARYA BACTERIA ARCHAEA Land plants
Dinoflagellates
Green algae
Forams
Ciliates
Diatoms
Red algae
Amoebas
Cellular slime molds
Euglena
Trypanosomes
Animals
Leishmania
Fungi
Sulfolobus
Green nonsulfur bacteria
Thermophiles
(Mitochondrion)
Figure The three domains of life, supported by the sequence from many sequenced genomes
Spirochetes
Halophiles
Chlamydia
COMMON
ANCESTOR
OF ALL
LIFE
Green
sulfur bacteria
BACTERIA
Methanobacterium
Cyanobacteria
both are prokaryotic
ARCHAEA
(Plastids, including
chloroplasts)

16. Cyanobacteria

17. Fig. 25-8
Figure 25.8 Banded iron formations: evidence of oxygenic photosynthesis
For the Discovery Video Early Life, go to Animation and Video Files.

19. Ceno- zoic Meso- zoic Humans Paleozoic Colonization of land Animals
Fig. 25-7
Ceno-
zoic
Meso-
zoic
Humans
Paleozoic
Colonization
of land
Animals
Origin of solar
system and
Earth 1 4
Proterozoic
Archaean
Prokaryotes
Figure 25.7 Clock analogy for some key events in Earth’s history
Billions of
years ago 2 3
Multicellular
eukaryotes
Single-celled
eukaryotes
Atmospheric
oxygen

20. Table 25.1

21. Origin of the eucaroytes

22. Table 25-1
Table 25.1

23. Table 25-1a
Table 25.1

24. Table 25-1b
Table 25.1