How much mass extinction has there been on earth?

5 mass extinctions

Specialists consider that there have been 5 mass extinctions on Earth.  It is widely known the fact that mass extinctions are periods in Earth’s history when large numbers of species die out simultaneously or within a limited time frame. Statistics show that the most severe occurred at the end of the Permian period when 96% of all species perished.  Here are the most important mass extinctions: Ordovician-Silurian mass extinction, Late Devonian mass extinction, Permian mass extinction, Triassic-Jurassic mass extinction and the Cretaceous mass extinction.