The Paleozoic era's Silurian period saw animals and plants finally emerge on land. But first there was a period of biological regrouping following the disastrous climax to the Ordovician.

The initial radiation of vascular land plants, evidenced by increases in both diversity and morphological disparity during the Silurian and ... explosion of marine animals. During this period ...

The most formidable of them were the armored placoderms, a group that first appeared during the Silurian ... land vertebrates, including dinosaurs and mammals. The fossils of these remarkable ...