But first there was a period of biological regrouping following the disastrous climax to the Ordovician ... The Silurian drew to a close with a series of extinction events linked to climate ...

These first steps toward life on land were cut short by the freezing conditions that gripped the planet toward the end of the Ordovician. This resulted in the second largest mass extinction of all ...

They believe a supernova explosion close to Earth could be to blame for both the late Devonian and Ordovician extinction events, which occurred 372 and 445 million years ago respectively.

Exploding stars in near-solar space may have triggered at least two mass extinction events in Earth ... stars—could be ...