Evolution

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What were the Major drivers of evolution?

1. Tectonic movement of continental plates

Subduction resulted in Volcanoes or Earthquakes, and mountains.

Recent Continental movement include:

Pangaea supercontinent during Permian Period

Formation of S. Hemisphere during Triassic period

Division of N. and S. America during Cretaceous period

2. Vulcanism

Resulted in local and global climates change, due to emission of gases and particles.

Formation of Islands-Galapagos and Hawaii

3. Climate change

4. Meteorites

Evidence for Continental Drift:

Tectonic plates

Fossil distribution

Magnetic fields

Consequences of Meteorites:

Large scale migration

Speciation

Mass extinction

Adaptive radiation

What were the Major Extinction events?

1. Permian - Triassic Mass Extinction

Defines boundary between Palaeozoic and Mesozoic eras. 96% of marine species wiped out and 70% land vertebrates wiped out.

Cause: Volcanic eruption in Serbia-Large amounts of lava, large production of CO2, which increased the global temperature by 6 degrees. The temperature difference between equators, lead to the slow mixing of ocean water, when lead to a decrease in Oxygen availability, which lead of marine extinction.

2. Jurassic - Cretaceous extinction

Mammal like reptiles replaced by dominant reptiles (dinosaurs) and mainly conifer- and fern- vegetation

3. Cretaceous - Paleogene Mass Extinction

Defines boundary between Mesozoic and Cenozoic eras. 75% of all species became extinct and 50% of insects.

Cause: Meteorite at Chixulub crater-evidence was the Iridium layer on sediments, commonly found on meteorites. Impacts: Huge tsunamis, cloud of dusts and water vapour blocked the sun, death of plants and phytoplankton and drastic climate change.

4. Ongoing Anthropocene extinction

Causes: Hunting, habitat destruction, industrial revolution, pollution, climate change and spread of invasive species and pathogens.

Geological Time and Continental Drift