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Plants first showed up on land around 700 million years ago.
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The earliest plants have been thought to have evolved from green algae ancestors.
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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.
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This included hornwort, liverwort, moss and tracheophyra.
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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.
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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.
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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.
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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.
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Plants continued to develop different structures. Seed plants developed and spore producing plants could not flourish because of this. Gymnosperms appeared during this time.
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Cycads and ginkgo's appeared. The climate also began to dry which led to the evolution of advanced conifers.
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Seed bearing plants dominated all other plants.
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The climate became wetter, leading to development of larger jungles and plants. Flower plants appeared during this time, but played minor role.
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Angiosperms which is where male or females reproductive organs are housed in flowers. Modern day trees appeared. Ancestors of modern day ferns evolved.
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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.
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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.