Geological Time Scale- Soummers

  • Precambrian Time 4600 MYA

    Precambrian Time 4600 MYA
    The Earth formed from planetary nebula. Oldest age-dated rocks on Earth. Fossil algae and strmatolites (prokaryotes). Fossil evidence of bacteria. Fossil evidence of cells with a nucleus (eukaryotes). First multi-celled organisms (seaweed and algae). Oldest marine worms and jellyfish.
  • Period: to

    Geological Time Scale in One Calendar Year

  • Quaternary Period 2 MYA

    Quaternary Period 2 MYA
    First of 4 ice ages - 1 MYA. Oldest direct human- ancestor fossil, Homo habilis - 1MYA. First modern man, Homo sapiens - 0.1 MYA. Mammoth and mastodon bones - 0.5 MYA. Revolutionary War - 235 years ago. World War II - 70 years ago.
  • 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 a 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 seed plants.
  • Mississippian Period 360 MYA

    Mississippian 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 Mesozoic, probably meteor or comet impact.
  • Cenozoic Era- The Age of Mammals - 65 MYA

    Cenozoic Era- The Age of Mammals - 65 MYA
  • Tertiary Period 65 MYA

    Tertiary 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.