Important timeline??

The Great Oxidation Event time

~2600mya

The Great Oxidation Event Causes/Consequences

CAUSE: evolution of CYANOBACTERIA → produced oxygen as a photosynthesis byproduct

RESULT:

• shift in atmospheric composition

• mass extinction of ANAEROBIC

• ozone layer formed

• dramatic shift in climate

• rise in AEROBIC/MULTICELLULAR life

End-Permian Time aka the great dying

~250mya

End-Permian Time aka the great dying CAUSES/RESULTS

CAUSE: large spike in atmospheric CO2 due to volcanic eruptions

RESULTS:

• global warming

  • hotter temps = water holds less O2 = harder for aquatic life

  • anoxia and acidification

  • severe extinction

Cretaceous-Paleogene Time

~66mya

Cretaceous-Paleogene CAUSES/RESULTS

CAUSES: Asteroid

RESULTS:

• ice age

• less sunlight so decrease in photosynthesis and primary produced

• wiped out dinos

***AND ENABLED RISE OF MAMMALS

consequences of the evolution of prokaryotes

~3.8bya

FIRST life on earth

anaerobic (b/c no O2 yet)

consequences of evolution of oxygen-producing photosynthesizers

~2.2mya??

triggered BY the GOE

formation of ozone layer

increase in aerobic life and decrease in anaerobic life

consequences of evolution of eukaryotes

~2000mya

OCCURRED BC OF ENDOSYMBIOSIS

more complexity (complex multicellular)

sexual reproduction and increasing genetic diversity

consequences of evolution of animals

~600mya

RAPID diversification of animal body

increase in pred/pray relationships and therefore an increase in natural selection

multicellularity allowed for tissue and organ specialization

consequences of movement of animals to land, and evolution of MULTIcell PLANTS

~460mya

colonization of ecological niches

plants came first → more oxygen

Diversification of terrestrial systems***

• there were plants on land to support those animals and whatnot

bones in fish

~440mya

diversification of body forms and colonization of dif ecological niches because increased support for muscles and structure and better/more efficient swimmers

first tetrapods

~415mya

colonization of diverse ecological niches BC MOVEMENT ONTO LAND was possible

overall timeline

evolution of prokaryotes 3800mya

oxygen-producing photosynthesizers 2700mya

GOE 2400mya

eukaryotes 2000mya

animals 600mya

animal movement to land (tetrapods)/multicellular plants 460mya

end-permian 250mya

cretaceous-paleogene 66mya