the first major extinction event took place in 2400 ma.
the first major extinction event took place in 2400 ma.
when did the first major extinction event take place?
2400 ma
Na
Na
the great oxygenation event, which occurred around 2.45 billion years ago, was probably the first major extinction event. since the cambrian explosion five further major mass extinctions have significantly exceeded the background extinction rate. the most recent and arguably best-known, the cretaceous–paleogene extinction event, which occurred approximately million years ago (ma), was a large-scale mass extinction of animal and plant species in a geologically short period of time. in addition to the five major mass extinctions, there are numerous minor ones as well, and the ongoing mass extinction caused by human activity is sometimes called the sixth extinction. mass extinctions seem to be a mainly phanerozoic phenomenon, with extinction rates low before large complex organisms arose.
extinction event