Geologic Time Scale-Sexton

By sextonm14
  • Precambrian Time 4600 MYA

    Precambrian Time 4600 MYA

    The Earth formed from planetary nebula. Oldest age-dated rocks on Earth. Fossil algae and strolites (prokaryotes). Fossil evidence of bacteria. Fossil evidence of cells of cells with a nucleus (eukaryotes). First multi-celled organisms (seaweed and algea). 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 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. Fist 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. Protocerarops. 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-60MYA. First ancestors of pigs and deer-57MYA. First horses-55MYA. First ancestors of rabbits 45 MYA. First monkeys - 39 MYA. Oldest human like ancestors (hominids)-4MYA
  • 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 sapians- 0.1 MYA. Mammoth and mastodon bones- 0.05 MYA. Revolutionary War- 235 years ago. World War II- 70 years ago.