Ethan C. Geologic Timescale

By ethclack1
  • Cambrian 570 - 500 MYA
    570 BCE

    Cambrian 570 - 500 MYA

    Earliest record of marine life. Trilobites are dominant.
  • Ordovician 500 - 435 MYA
    500 BCE

    Ordovician 500 - 435 MYA

    Invertebrates are dominant, mollusks become abundant. Earliest fish that are jawless and later, jawed and armored fish.
  • Silurian 435 - 395 MYA
    435 BCE

    Silurian 435 - 395 MYA

    Earliest terrestrial plants and animals. Tiktaalik eurypterids develop.
  • Devonian 395 - 345 MYA
    395 BCE

    Devonian 395 - 345 MYA

    Armored fish go extinct, but an abundance of several species of fish. Earliest amphibians and ammonites
  • Carboniferous 345 - 280 MYA
    345 BCE

    Carboniferous 345 - 280 MYA

    Abundant sharks and amphibians. Large swamps and coal forming forests. Earliest reptiles, scale trees and fern seeds.
  • Permian 280 - 225 MYA
    280 BCE

    Permian 280 - 225 MYA

    Extinction of many types of marine animals including trilobites.
  • Triassic 225 - 195 MYA
    225 BCE

    Triassic 225 - 195 MYA

    Earliest dinosaurs, abundant cycads and conifers.
  • Jurassic 195 - 136 MYA
    195 BCE

    Jurassic 195 - 136 MYA

    Earliest birds and mammals. Abundant dinosaurs and ammonites.
  • Cretaceous 136 - 65 MYA
    136 BCE

    Cretaceous 136 - 65 MYA

    Earliest flowering plants, climax of dinosaurs followed by their extinction. great decline of brachiopods. Abundance of bony fish.
  • Tertiary 65 - 1.8 MYA
    65 BCE

    Tertiary 65 - 1.8 MYA

    Earliest placental mammals, modern mammals, large running mammals.