History of the Earth, Oceans and Life~4.7 billion years ago (bya)- Earth forms~4.2 bya- Oceans form~3.6 bya- Life begins~2.0 bya- Oxygen rich atmosphere~570 million years ago (mya)- First animals~65 mya- Dinosaurs go extinct~1 mya- First hominids~230 years ago- U.S.A is formed ~29 years ago- Woody was formed

Early Earth

How Life Started

to vacuum pump

boiling water

sparkdischarge

liquid water in trap

water containingorganic compounds

water droplets

water in

condenser

electrodes

water out

CH4

NH3

H2OH2

gases

spontaneous formation of lipids,carbohydrates, amino acids, proteins,nucleotides under abiotic conditions

livingcells

self-replicating system enclosed in aselectively permeable, protective lipid sphere

DNA RNA enzymes andother proteins

formation ofprotein-RNA systems,

evolution of DNA

formation oflipid spheres

membrane-bound proto-cells

3.8 3.2 2.5

Cyclic pathway ofphotosynthesis

Noncyclic pathwayof photosynthesis

Aerobic respiration

Origin ofProkaryotes

Eubacterial Lineage

Ancestors of Eukaryotes

ArchaebacterialLineage

billion years ago

origins of eukaryotes

origins of animals

origins of fungi

origin of mitosis, meiosis

endosymbiotic origins of mitochondria

endosymbiotic origins of chloroplasts

1.2billion years

ago

900million years

ago

435million years

ago

ARCHAEBACTERIAExtreme halophilesMethanogensExtreme thermophiles

EUKARYOTESAnimals

Heterotrophic protistans

Fungi

Photosynthetic protistans

Plants

EUBACTERIAOxygen-producing

photosynthetic eubacteria

Other photosynthetic

eubacteria

Heterotrophic and

chemoautotrophic eubacteria

origins of plants

Photosynthetic protistans