-
Cambrian 570 M-500 Mya
earliest record of marine life. Trilobites are the dominant species -
Ordovician 500M- 435 Mya
Invertebrates are dominant, mollusks become abundant. Earliest Fish that are Jawless and later, jawed and armored fish. -
Silurian 435 M- 395 Mya
Earliest terrestrial plants and animals. -
Devonian 395 M- 345 Mya
Armored fish go extinct, but abundance of several species of fish. Earliest amphibians and ammonites. -
Carboniferous 345M-280 Mya
Abundant sharks and amphibians. Large swamps and coal forming forests. Earliest reptiles. Scale trees and seed ferns. -
Permian 280 M-225 Mya
Extinction of many types of marine animals including trilobites. -
Triassic- 225M-195 Mya
Earliest Dinosaurs, abundant cycads and conifers -
Jurassic- 195M-136 Mya
Earliest birds and mammals abundant dinosaurs and ammonites -
Cretaceous- 136M-65 Mya
Earliest flowering plants, climax of dinosaurs followed by their extinction. Great decline of brachiopods. Abundance of bony fish. -
Tertiary- 65 M- 1.8 Mya
Earliest Placental Mammals, modern mammals, large running mammals -
Quaternary- 1.8 M – Present
Large Carnivores, Neanderthals, Humans, mastodons
