Notes

End Cretaceous Mass Extinction Event
-A 6-mile wide asteroid crashed into the earth 66 million years ago. It caused tsunamis, acid rain, short-term global cooling, and widespread ecosystem collapse. Many species went extinct.
-The only surviving group of dinosaurs was birds.

Asteroid Impact Triggers DInosaur Mass Extinction
-Days After Impact: Shock waves, tsunamis, wildfires, dust, and water vapor
-Weeks: Low temperatures, acid rain, and troubled ecosystems
-Months: Devastated landscapes
-Years: Recovery Begins
-Centuries: Plants recover

Rainforests Spread Across the Globe
-Warm Climates provided for rainforests across the globe. These rainforests provided habitat for snakes, primates, and birds. These primates developed grasping hands and forward-facing eyes to help with climbing and identifying things in the forest. Large brains were developed for dexterity and hand-eye coordination.

Ice Age Mastodon
-About 56 million years ago, the CO2 in the atmosphere doubled in a few thousand years. Global temperatures spiked 10-11 degrees Fahrenheit.
-Animals and plants that survived better in hot and dry climates thrived.
-Plants became less nutritious because they store less protein under higher CO2.
-For whatever reason, a lot of animals got smaller in size.

Ice Age Extinction Event 2
-Few African animal species went extinct during the recent ice ages.
-17% of animal species in Africa over 110 pounds disappeared between 50,000-10,000
-Human hunting, habitat change, and changing climate caused 18% of animals species over 110 pounds to disappear in Eurasia between 45,000-4,000 years ago.
-Human hunting and increasingly dry climate killed 97% of animals over 110 pounds in austraia tHe saltwater crocdile and the red kangaroo are the only surviving wild animals. 50,000-40,000 years ago.
-74% of North America 14,000 years ago

A Giant Deer and a Bison Mummy
-As ice sheets expanded, sea levels dropped, revealing land bridges. Animals and humans migrated between asia and north america over a land bride called Beringia.