Mass Extinctions

Mass extinctions happen when a huge number of species die out in a short time. Earth has had five major mass extinctions. Each one changed the course of life on our planet. After each extinction, new types of animals evolved to fill the empty spaces.

The Big Five

The five biggest mass extinctions happened over the past 450 million years. The worst one was the Permian extinction, which killed 90 percent of all species. The most famous is the one that killed the dinosaurs 66 million years ago. Each extinction was caused by different things, like volcanoes, asteroids, or climate change.

Life Bounces Back

After every mass extinction, life recovered. New species evolved to take the place of the ones that were lost. After the dinosaurs died, mammals took over. Without mass extinctions, humans might never have evolved. These events are terrible but they make room for new kinds of life.

Fun Facts

• The Permian extinction was so bad it is called "The Great Dying" — 90% of all species were lost.
• After the dinosaurs went extinct, mammals evolved to fill the empty niches in just a few million years.
• Earth has had five major mass extinctions in the past 450 million years.

Did You Know?

Some scientists think we are in a sixth mass extinction right now, caused by human activities. Species are going extinct much faster than normal. This is why protecting endangered animals and their habitats is so important!