During the Ordovician period, the concentration of CO2 in the earth's atmosphere was about eight times higher than today. It has been hard to explain why the climate cooled and why the Ordovician ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

Fossils from 465 million years ago recently discovered in Portugal have revealed the huge size reached by trilobites, the most diverse group of extinct marine arthropods. Geologists describe the ...

Since the beginning of time, Earth has created life and then wiped out most of it in catastrophic, ultra-destructive moments.

Over half a billion years ago, during the Cambrian geological period, life on Earth started to get a lot more interesting. Thanks to the rise in free oxygen generated mostly by photosynthesizing algae ...

Learn more about the time period that took place 488 to 443 million years ago. 3 min read During the Ordovician period, part of the Paleozoic era, a rich variety of marine life flourished in the vast ...

How long did the Ordovician period last, and what caused the Ordovician mass extinction to wipe out 85 percent of life on earth 445 million years ago? Long before the dawn of humans, dinosaurs, ...

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The Paleozoic Era, which ran from 541 million to 251.9 million years ago, was a time of great change on Earth. The era began with the breakup of one supercontinent and the formation of another. Plants ...