Mass Extinction

By Trinidy Campbell
  • 4004 BCE

    Beginning of Earth

    Beginning of Earth
    The earth became in existence 4.6 million years ago.
  • 3008 BCE

    Life Beginning

    Life Beginning
    Life Began 3.85 billion years ago.
  • 215

    The Triassic Period

    The Triassic Period
    This period occurred between 215 and 199 million years ago. During this period climate was very dry with very hot summers and cold winters. 95% of marine genera were obliterated because of high carbon dioxide levels. By the end of this period tectonic forces had slowly begun to split the supercontinent in two.
  • 299

    The Permian Period

    The Permian Period
    This period lasted from 299 to 251 million years ago. It was the worst extinction in the planets history. This extinction affected the marine communities the most. It destroyed more than 90 percent of all marine species and 70 percent of land animals. Scientists think this mass extinction was caused by a series of volcanic eruptions that pumped so much debris into the air it blocked out the sun and caused a drop in temperature.
  • 416

    The Devonian Period

    The Devonian Period
    The Devonian period occurred from 416 million years ago to 350 million years ago. It was named after Devon,England where the old red sandstone of the Devonian was first studied. During this time period there were important changes in in the land masses on the globe. Also thousands of species of fish developed in the Devonian sea. This extinction hurt the water animals more than the land. The sponges and corals were the most affected by it.

  • The Ordovician Period

    The Ordovician Period
    The Ordovician period lasted almost 45 million years. During this time period the are north of the tropics was was almost entirely ocean. The cause of this mass extinction was that the Earth experienced a milder climate , so the weather was warm and the atmosphere contained mostue. During the time period massive glaciers formed causing shallow seas to drain and sea levels to drop. In the end 60% of all marine invertebrate genera and 25% of all families went extinct.

  • The Cretaceous Period

    The Cretaceous Period
    This period lasted approximately 79 million years. At the beginning of this period dinosaurs ruled the land. When a temperature spike happened in the mid-Cretaceous, the climate began to cool and the tenor changed. At the end of the period most of the life was perished.