- Paleozoic, Paleozoic era - from 544 million to about 230 million years ago
--1 is a kind of era, geological era
--1 has parts:Permian, Permian period; Carboniferous, Carboniferous period; Devonian, Devonian period, Age of Fishes; Silurian, Silurian period; Ordovician, Ordovician period; Cambrian, Cambrian period