The Geologic Column

  • proterozoic

    proterozoic
    simple multicelular sea creatures develop, algae and plankton develop, eukayotic cells develop (2,500,000,000)
  • Paleozoic

    Paleozoic
    -permian: modern insects; reptiles spread; evergreens; extinction of trilobites ( on year 299,000,000
    - pennsylvanian: giant insects; first reptiles (318,100,00)
    -mississippian: first amphibians; freshwater fish; wingless insects(359,200,00)
    - devonian: land colonized by arthropods and plants(443,700,00)
    -silurian: land conolized by athropods and plants (443,700,000)
    -ordovivian: trilobites abundant; vertebrates increase (488,300,000)
    -cambrian: sudeen explosion of life; (542,000,000
  • Phanerozoic; cenozoic

    Phanerozoic; cenozoic
    quatenary: recent (holocene}9 epoch pleistocene Epoch
    tetiary: piocene Epoch
    -miocene Epoch
    -oligocene Epoch
    - eocene Epoch
    -paleoncene Epoch
    End of last ice age, rise of human civilization.
    The Pleistocene Epoch is typically defined as the time period that began about 2.6 million years ago and lasted until about 11,700 years ago.
  • mesozoic

    mesozoic
    -cretaceous
    -jurassic
    -triassic
    cretaceous: mass extinctions (including dinosaurs); flowering plants appear
    Jurassic: giant dinosaurs; early birds; first mammals
    Triassic: first dinosaurs; rise of mammal-like reptiles