 |
Most types of coral died out during the Ordovician Period -- 440 million years ago.
© Dan Wagner |
|
|
Most Extinctions Occur in Huge Clusters
The overwhelming majority of species have died out in extinctions of enormous magnitude that occur over short periods of time. Five mass extinctions on a global scale have taken place on Earth since the close of the Cambrian Period about 570 million years ago.
#1: The first of these occurred around 440 million years ago, near the end of the Ordovician Period, when all life forms lived in the oceans. In many groups, like corals and fish, only a few species survived.
|
 |
|
3 of 17 |
|
 |
|
|
|