-
Cambrian 500-570 ma
earliestperiod of marine life-trilobites are dominant. -
Ordovician 435-500 ma
Echinoderms, starfish, sand dollar, sea urchin, and sea cucumbers. Invertabrates are dominant, mollusks become abundant, earliest fish that are jawless and, later jawed armored fish. -
Silurian 395-435 ma
Earliest terrestrial plants, and animals. Tiktaalik, Eurypterids develope. -
Devonian 345-395 ma
Armored fish go extinct, but Abundance of several species of fish, earliest Amphibians and ammonites. -
Carboniferous 280-345 ma
Abundant sharks, and amphibians, large swamps, and coal forming forests. Earliest reptiles, scale trees, and seed ferns. -
Permian 225-280
Extinct of many types of marine animals imcluding Trilobites
