Timetoast Geologic Timeline

By ciana_jefferson
  • 252 BCE

    Triassic 252-200MYA

    Triassic 252-200MYA
    Rise of reptiles, and first dinosaurs appeared. Climate was hot and dry with strong seasons, making summers hot and winters cold. Earliest mammal evolved.
  • 66

    Tertiary 66-2.6MYA

    Tertiary 66-2.6MYA
    Enormous change to biology, climate, and oceanography. Mammals, plants, insects, seas life, and birds develop to repopulate earth. Geologic changes form glaciers and other landmass.
  • 148

    Cretaceous 148-66MYA

    Cretaceous 148-66MYA
    Development of flowering plants. World was a warm place with no seasons. Ancient birds developed, and dinosaurs continue to flourish and create new species. (K-Pg) Paleogene extinction ends dinosaur life.
  • 200

    Jurassic 200-145MYA

    Jurassic 200-145MYA
    Supercontinent pangea begins to drift apart. Marine life diversified, and small mammals developed. Reptiles and dinosaurs dominated the lands.
  • 280

    Permian 280-255MYA

    Permian 280-255MYA
    Large mass extinction of many types of marine animals including trilobites.
  • 345

    Carboniferous 345-280MYA

    Carboniferous 345-280MYA
    Abundance of sharks and amphibians.Large swamps and coal forming forests. Earliest reptiles, scale trees and seed ferns appear.
  • 395

    Devonian 395-345MYA

    Devonian 395-345MYA
    Armored fish go extinct, but abundance of several other fish species occur. Earliest amphibians and ammonites.
  • 435

    Silurian 435-395MYA

    Silurian 435-395MYA
    Earliest terrestrial plants and animals. Tiktaalik eurypterids developed.
  • 500

    Ordovician 500-435M

    Ordovician 500-435M
    Echinoderms exist- Starfish, sand dollar, sea urchin, sea cucumber. Invertebrates are dominant, mollusks become abundant. Earliest fish are jawless, but later fish become jawed and armored.
  • 570

    Cambrian 570-500MYA

    Cambrian 570-500MYA
    Earliest record of marine life. Trilobites, are very dominant.

  • Quaternary 2.6MYA-present

    Quaternary 2.6MYA-present
    Glaciers continue to expand. Lands continue to change and form to how we see them today. Ice age conditions lead to extinction of mammals such as the mammoth. Humans develop and take over.