Crazy Mass Extinctions
From what we know, Earth has experienced five mass extinctions. However, some scientists believe Earth is currently in its sixth mass extinction. The worst mass extinction ever experienced on Earth occurred 250 million years ago, and it wiped out more than 70% of land life and 95% of ocean life.
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Key Facts In This Video
Over 99% of all the animal species that have ever lived are now extinct. (0:00)
Plants were the cause of the mass extinction that occurred about 374 million years ago. (0:57)
Carbon dioxide levels have climbed at least 25% over the last 50 years. (3:07)