paleozoic era Definition

paleozoic, jurassic period, triassic period, devonian period, permian period, cretaceous period, archeopteryx, mesozoic era, cambrian period, carboniferous period, pleistocene epoch, brachiopods, laurasia, dinosaurs, oligocene epoch, ostracods, hadean, sauropod dinosaur, eocene epoch, pliocene epoch, gondwanaland, stegodon, cenozoic era, trilobites, miocene epoch, carboniferous, crinoids, faunas, prehistoric, mesozoic, baleen whale, stromatolite, pleistocene, paleocene, conodonts, fossil, homo heidelbergensis, mammuthus, tertiary period, fossilised, mya, upper paleolithic, habilis, precambrian, fossilized, cenozoic, theropod dinosaur, robustus, archaeopteryx, iguanodon, utahraptor, phanerozoic, neogene, supercontinent, hadrosaur, noachian, australopithecines, interglacial, ichthyosaurs, ankylosaurus, hominoids, psittacosaurus, tyrannosaurus rex, paleolithic age, eocene, mesolithic, plesiosaurs, paranthropus, genus australopithecus, periodical cicada, homo habilis, neolithic age, camarasaurus, placentals, tyrannosaurs, pliocene, megafauna, horned dinosaur, cretaceous, australopithecus africanus, mastodons, middle paleolithic, isopods, coprolite, dinosauria, diplodocus, smilodon, ceratopsian, braincase, anthropoids, stegosaur, homo erectus, theropods, allosaurus, paleolithic, palaeontological, prehistory, ankylosaur, ornithopod, paleogene,