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Age of Dinosaurs

Cretaceous Period

Tyrannosaurus rexTyrannosaurus rexThe Cretaceous Period, the last part of the Mesozoic Era, extended from 145 to 66 million years ago. As the supercontinents of Laurasia and Gondwana continued to drift apart, each landmass carried its own dinosaur species with it. Cut off from others of their own kind by the sea, dinosaurs began to evolve into different species, adapting to the changing climates wherever they lived. This is the reason why so many new species of dinosaurs appeared during the Cretaceous Period. The ornithischians (“bird-hipped”) become much more abundant, while some slow, lumbering Jurassic sauropods died out. One group of sauropods, the titanosaurs, thrived, however, especially in South America. Some of them were the largest land animals that ever walked the Earth.

Cretaceous world

A map of the world in Cretaceous timesA map of the world in Cretaceous timesA scene in Cretaceous Africa, 112 million years agoA scene in Cretaceous Africa, 112 million years ago
The Cretaceous Period saw the break-up of the great supercontinents, Laurasia and Gondwana, the northern and southern halves of Pangaea, into smaller landmasses. Vast, shallow seas covered much of North America and Europe. Chalk formed from the remains of tiny living things that collected on the beds of these seas.

There was a gradual change in the climate. As the Cretaceous went on, it became cooler and drier. A wide variety of plant life grew in all parts of the world, including Antarctica. Flowering plants, including deciduous trees, which had evolved during the Jurassic, replaced some of the more ancient plant species.

Dinosaurs of Australasia-AntarcticaDinosaurs of Australasia-Antarctica 

The name Cretaceous takes its name from the Latin word for chalk, creta.

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