Mass Extinctions

Mass Extinctions

Mass Extinction Event: The phenomenon in which a large number of species of life on earth become extinct in a relatively short period of time.   There have been five mass extinction events: 1. Ordovician 2. Devonian    3. Permian-Triassic 4. Triassic-Jurassic 5. Cretaceous-Paleogene

Ordovician

450-440 million years ago cause: continental drift/glaciation 60%-70% of species went extinct  

Devonian

375-360 million years ago cause: extreme climate change (global cooling) 75% of species went extinct

Permian-Triassic

251 million years ago cause: meteor impacts, volcanic eruptions, global warming 90%-96% of species went extinct

Triassic-Jurassic

200 million years ago cause: extreme volcanic activity 60%-70% of species went extinct

Cretaceous-Paleogene

65.5 million years ago cause: asteroid collision, debris blocked the sun 75% of species went extinct