Cretaceous period

Cretaceous period krĭtāˈshəs [key], third and last period of the Mesozoic era of geologic time (see Geologic Timescale, tablegeologic timescale, table), lasting from approximately 144 to 65 million years ago. The Cretaceous was marked, in both North America and Europe, by extensive submergences of the continents. Changes both in the earth's surface and in its flora and fauna brought the Mesozoic to a close.

Sections in this article:

• Introduction
• Evolution of Plant and Animal Life
• Movement of the Continents
• The Upper Cretaceous Period
• The Lower Cretaceous Period

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