The Paleozoic era's Silurian period saw animals and plants ... organisms was stoked by oceans teeming with tiny planktonic creatures. Waiting at the other end of the food chain were the fearsome ...

3 min read The Cambrian period, part of the Paleozoic era, produced the most intense ... These toughened-up creatures represented a crucial innovation: hard bodies offering animals both a defense ...

This reptilian skin fossil belongs to a creature from the early Paleozoic era that led terrestrial and ... closely resembles amniotes - terrestrial creatures that developed the capability to ...