Australia: The Land Where Time Began

A biography of the Australian continent 

Periodicity of Extinction Events

Statistical analysis of the fossil record suggests that extinction events occur about every 26 million years. These events are times when the extinction rate is above the background rate of extinction/renewal normally seen in the fossil record. Meteorite impacts also show a pattern where clusters of impacts occur every 26-30 million years. Bursts of plate tectonic activity and volcanic activity also appear to show a cyclic pattern, but more work is needed to sort out how long these cycles are, if it can be shown that they exist.

Mass extinction events

Sources & Further reading