Geologic Time Scale- Atwood

By TabbyMA

  • Precambrian Time 4600 MYA

    Precambrian Time 4600 MYA
    The Earth formed from planetary nebula. Oldest age-dated rocks on Earth. Fossil algae and stromatolites (prokaryotes). First multi-celled organisms ( seaweed and algae). Oldest marine worms and jellyfish.
  • Period: to

    Geologic Time Scale in One Calender Year

  • Origin of Life ( First Cells) 3900 MYA

    Origin of Life ( First Cells) 3900 MYA
    3900 million years ago

  • Prokaryotes 3600 MYA

    Prokaryotes 3600 MYA

  • Eukaryotes 2100 MYA

    Eukaryotes 2100 MYA

  • Paloezoic Era 544 MYA

    Paloezoic Era 544 MYA

  • Cambrian Period 544 MYA

    Cambrian Period 544 MYA
    Burgess Shale animals. Animals with notochord.

  • Ordovician Period 544 MYA

    Ordovician Period 544 MYA
    First Fish. First Fossil evidence of land plants.

  • Silurian Period 438 MYA

    Silurian Period 438 MYA
    First Vascular land plants. Oldest lung fish fossils.

  • Devonian Period 408 MYA

    Devonian Period 408 MYA
    Oldest fossil evidence of mosses. First insects. First lobe-finned fish. First land animals. First sharks. First speed plants.

  • Mississipian Period 360 MYA

    Mississipian Period 360 MYA
    First possible reptiles.

  • Pennsylvanian Period

    Pennsylvanian Period
    Permian system begins. Snail-backed reptiles (Dimetrodon). End of Paleozoic. 96% of all life on earth perishes.

  • Mesozoic Era "The Age of Reptiles" 245 MYA

    Mesozoic Era "The Age of Reptiles" 245 MYA

  • Triassic Period 245 MYA

    Triassic Period 245 MYA
    First crocodiles First dinosaurs First mammals (Shrew like) First turtles.

  • Jurassic Period 208 MYA

    Jurassic Period 208 MYA
    Dilophosaurus, early dinosaur. First bird- Archeopteryx. Apatosaurus and Brachiosaurus. Stegosaurus.

  • Cretaceous Period 144 MYA

    Cretaceous Period 144 MYA
    First flowering plants. Duck-Billed dinosaurs. Protoceratops. Triceratops. Tyrannosaurus rex. Velociraptor. End of Mesozioc, probaly meteor or comet impact.

  • Cenozoic Era- Age of the Mammals- 65 MYA

    Cenozoic Era- Age of the Mammals- 65 MYA

  • Teriary Period 65 MYA

    Teriary Period 65 MYA
    First ancestors of dogs and cats- 64 MYA. Grasses become widespread- 60 MYA. First ancestors of pigs and deer- 57 MYA. First horses- 55 MYA. First ancestors of rabbits 45 MYA. First monkeys- 39 MYA. Oldest human like ancestors (hominids)- 4 MYA.

  • Quaternary Period 2 MYA

    Quaternary Period 2 MYA
    First of 4 ice ages- 1 MYA. Oldest direct human- ancestor fossil, Homo habilis- 1 MYA. First modern man, Homo sapiens- 0.1 MYA. Mammoth and mastodon bones- 0.05 MYA. Revolutionary War- 235 Years ago. World War II- 70 years ago.