Geologic Timeline

  • Cambrian 500-570 MA

    Cambrian 500-570 MA
    Earliest period of marine life.
    Trilobites are dominant.
  • Ordovician

    Echinoderms, starfish, sand dollar, sea urchin, and sea cucumbers.
    Invertabres are dominant, mollusks become abundant, earliest fish are jawless and later, jawed armored fish come around.
  • SIlurian 395-435 ma

    SIlurian 395-435 ma
    Earliest terrestrial plants and animals. Tikaalik and Eurypterids develop.
  • Devonian 345-395 ma

    Devonian 345-395 ma
    Armored fish go extinct, but abundance of several species of fish. Earliest amphibians and ammonites.
  • Carboniferous 280-345 ma

    Carboniferous 280-345 ma
    An abunbundance of sharks and amphibians. Large swamps, and coal foarming forests. Earliest reptiles, scale trees, and seed ferns.
  • Permian 225-280

    Permian 225-280
    Many marine animals went extinc including Trilobites.
  • Triassic 225m-195m

    Triassic 225m-195m
    Earliest dinosaurs, abundant cycads and conifers.
  • Jurassic 195m-136m

    Jurassic 195m-136m
    Earliest birds and mamals emerge. Abundant dinosaurs and ammonites.
  • Cretaceous 136m-65m

    Cretaceous 136m-65m
    Earliest flowering plants, climax of dinosaurs followed by their extinction. Great decline of brachiopods. Abundance of bony fish.
  • Tertiary 65m-1.8m

    Tertiary 65m-1.8m
    Earliest placental mammals, modern mammals, and large running mammals.
  • Quaternary 1.8m-prestent

    Quaternary 1.8m-prestent
    Abundance of large carnavors.