3 min read During the Ordovician period, part of the Paleozoic era, a rich variety of marine life flourished in the vast seas and the first primitive plants began to appear on land—before the ...

The oldest echinoids come from the Late Ordovician Period and ... but we know very little about this period in the group's history. In the Triassic both cidaroids and euechinoids started to diversify, ...

Over a period of 30 million years, prehistoric worms may have been the silent players in one of the greatest diversifications ...

Inspired by the early life forms of prehistoric worms and other invertebrates that triggered the Great Ordovician ...