The "Big Five" mass extinctions of the Phanerozoic Eon have long attracted significant attention from the geoscience ...

The Ordovician period, from 485 to 444 million years ago, was a time of dramatic changes for life on Earth. Over a 30-million-year stretch, species diversity blossomed, but as the period ended ...

However, sometime around 445 million years ago, 85 percent of species went extinct over the relatively short interval of 1.4 million years. This unprecedented die-off is now known as the earth’s first ...

Sharks have been around for hundreds of millions of years, appearing in the fossil record before trees even existed. But what did they evolve from, are they ‘living fossils’, and how did they survive ...

A cataclysmic shift at the end of the Ordovician led to the disappearance of about 85% of species at a time when life was mostly limited to the seas. “Their link to those mass extinctions ...

The "Big Five" mass extinctions of the Phanerozoic Eon have long attracted significant attention from the geoscience ...

One of Earth's most consequential bursts of biodiversity—a 30-million-year period of explosive evolutionary changes spawning innumerable new species—may have the most modest of creatures to ...