Theory for the Permian Extinction: 250 million years ago
1. Siberian Traps: Volcanoes erupted in this area of Russia for a million years.
2. The gases from these volcanoes fill the atmosphere with CO2. This causes global warming due to the Greenhouse effect. The Earth goes through a period of intense global warming.
3. Global warming causes the oceans to heat up. Warm water holds less oxygen then cool water.
4. Certain types of bacteria thrive without oxygen. These bacteria begin to spread over all the Earth’s oceans. These bacteria give off hydrogen sulfide, which is a poisonous gas, killing ocean life.
5. The hydrogen sulfide gas moves out of the oceans and poisons the atmosphere killing life on land.
The Permian extinction wiped out 96% of ocean life and 70% of life on land. This ended the Paleozoic Era, and led to many different forms of life in the Mesozoic.