Paleozoic Era Plants And Animals
During the Cambrian period, there were monoplacophorans which might have been descended from annelids, there were also agnathans, myllokunmingia haikouichthys, and trilobites. During the Ordovicion period, there were dolioduses and cladoselachees. During the Silurian period, there were arachnids. Examples of arachnids are spiders, scorpions, and mites. There were also jaekelopterus rhenaniae, brontoscorpio, and cooksonia. During the Devonian there were tiktaaliks and elginerpetons. During the Carboniferous there were anapsids. During the Permian period there were pelycosaurs, therapsids, mollusks, echinoderms, and brachiopods.