he first true plants began to take root on land some 430 million years ago. They evolved rigid stems, enabling them to stand upright, and the tubular tissues common to all vascular plants that allowed the transport of water and nutrients. These first colonizers lacked leaves, but mosses and other plants followed, providing a thin layer of waterside vegetation that encouraged more aquatic animals to make the transition to land.
The climate remained warm and stable throughout most of the Silurian. The supercontinent of Gondwana was still positioned over the South Pole but the vast icecaps of the late Ordovician period melted almost to nothing. Sediments formed from massive quantities of broken shells suggest violent storms were triggered by the warmth of tropical oceans.
The Silurian drew to a close with a series of extinction events linked to climate change; however, these were relatively minor compared with those of other geologic periods.
The climate remained warm and stable throughout most of the Silurian. The supercontinent of Gondwana was still positioned over the South Pole but the vast icecaps of the late Ordovician period melted almost to nothing. Sediments formed from massive quantities of broken shells suggest violent storms were triggered by the warmth of tropical oceans.
The Silurian drew to a close with a series of extinction events linked to climate change; however, these were relatively minor compared with those of other geologic periods.
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