V >> Glossary Index
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Jurassic (jer-ASS-ik) is the name of the middle period of the Mesozoic
Era, which began 208 million years ago and ended 145 million years ago.
Its name is derived from the Jura Mountains in France. It was during this
period that the largest dinosaurs known lived. The climate of Earth during
the Jurassic was moist. Rainfall increased and the oceans rose. Lush vegetation,
resembling the profuse growth in today's rain forests, covered much of
Earth's surface, displacing the desert areas of the Triassic. Evidence
of the abundant plant life can be found in the extensive coal fields that
date from this period. Benettitalean cycads, ferns, and tree ferns (leaves
perched high atop thin trunks), conifers, and giant club moss dominated
the forests and marshlands.