Katlyn Spong Evolution of Plants

By sponkatl
  • 4000 BCE

    Pre Cambrian Era

    Plants first showed up on land around 700 million years ago.
  • 4000 BCE

    Evolution

    The earliest plants have been thought to have evolved from green algae ancestors.
  • 541 BCE

    Cambrian Period

    Most plant life was living in temperatures of 120 degrees. It was consisted of small, soft, marine plants. Terrestrial plants evolved which helped cool the climate and provide oxygen.
  • 541 BCE

    Bryophyta

    This included hornwort, liverwort, moss and tracheophyra.
  • 485 BCE

    Ordovician Period

    The plants were non-vascular which meant they weren't able to conduct water. They had to live in rather moist environments to thrive and reproduced by spores.
  • 443 BCE

    Silurian Period

    The first vascular plants evolved during this period. Although these plants had no difference in appearance, the adaption of vascular systems enabled land plants to stand upright and water go upward in their structure.
  • 419 BCE

    Devonian Period

    Plants developed sexual organs for reproduction, stems with vascular tissue, woody tissue for structure, and stomates for respiration. Ecosystems were dominated by plants, and many plants reproduced by bearing seeds. Carbon Dioxide levels dropped and oxygen levels increased.
  • 419 BCE

    Lignin

    This is a tough carbohydrate molecule that is water fearing. It adds support to vascular tissues in the stems. It also waterproofs the tissues so they don't leak.
  • 358 BCE

    Carboniferous Period

    Plants continued to develop different structures. Seed plants developed and spore producing plants could not flourish because of this. Gymnosperms appeared during this time.
  • 299 BCE

    Permian Period

    Cycads and ginkgo's appeared. The climate also began to dry which led to the evolution of advanced conifers.
  • 251 BCE

    Triassic Period

    Seed bearing plants dominated all other plants.
  • 201 BCE

    Jurassic Period

    The climate became wetter, leading to development of larger jungles and plants. Flower plants appeared during this time, but played minor role.
  • 145 BCE

    Cretaceous Period

    Angiosperms which is where male or females reproductive organs are housed in flowers. Modern day trees appeared. Ancestors of modern day ferns evolved.
  • 66 BCE

    Tertiary Period

    Grasses evolved during this time period leading to development of savanna ecosystems and plants. Conifers thrived in colder climates and flowering and fruits plants dominated in tropical climates.
  • 1 BCE

    Quaternary Period

    Humans first appeared during this period. They cultivated plants as their food source. They ate grains like wheat and barley. Later, they cultivated corn, squash, beans, rice, and millet.