Geologic Time Scale--Hopkins

By HopkinsA14
  • 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). 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

    Geologic Time Scale in One Calendar 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

  • Paleozoic Era 544 MYA

    Paleozoic 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-Archaeopteryx. Apatosaurus and Brachiosaurus. Stegosaurus.
  • Cretaceous Period

    Cretaceous Period

    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

  • 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.

  • 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.