Humans on fast lane to early extinction

MORE THAN 99% of documented living species are now extinct. Extinction is a natural and inevitable process that is compensated for by ‘speciation’, the development of new species.

But occasionally through the millennia the natural background rate for extinctions spikes sharply upwards. These are called Great Extinction Events.

The evidence for extinction events is based on fossils so it largely ignores microbial life, which doesn’t fossilise well, and concentrates heavily on marine life, which provides the best fossils. Most scientists recognise five major events in the past half a billion years, when larger and harder creatures have been around.