Mesozoic Era summary

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Below is the article summary. For the full article, see Mesozoic Era.

Mesozoic Era, Second of the Earth’s three major geologic eras and the interval during which the continental landmasses as known today were separated from the supercontinents Laurasia and Gondwana by continental drift. It lasted from c. 251 to c. 65.5 million years ago and includes the Triassic, Jurassic, and Cretaceous periods. The Mesozoic saw the evolution of widely diversified and advanced flora and fauna, quite different from those that had developed earlier during the Paleozoic Era or that would develop later during the Cenozoic Era.

George Gaylord Simpson Summary

George Gaylord Simpson was an American paleontologist known for his contributions to evolutionary theory and to the understanding of intercontinental migrations of animal species in past geological times. Simpson received a doctorate from Yale University in 1926. He chose for the subject of his

Jurassic Period Summary

Jurassic Period, second of three periods of the Mesozoic Era. Extending from 201.3 million to 145 million years ago, it immediately followed the Triassic Period (251.9 million to 201.3 million years ago) and was succeeded by the Cretaceous Period (145 million to 66 million years ago). The Morrison

Cretaceous Period Summary

Cretaceous Period, in geologic time, the last of the three periods of the Mesozoic Era. The Cretaceous began 145.0 million years ago and ended 66 million years ago; it followed the Jurassic Period and was succeeded by the Paleogene Period (the first of the two periods into which the Tertiary Period

Triassic Period Summary

Triassic Period, in geologic time, the first period of the Mesozoic Era. It began 252 million years ago, at the close of the Permian Period, and ended 201 million years ago, when it was succeeded by the Jurassic Period. The Triassic Period marked the beginning of major changes that were to take