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Age of Dinosaurs

Triassic Period

Plateosaurus, a Triassic prosauropod dinosaurPlateosaurus, a Triassic prosauropod dinosaurThe Age of Dinosaurs, the Mesozoic Era, began with the Triassic Period, 252–201 million years ago. The period began at a time when a vast number of animals, both on land and in the sea, became extinct. Scientists believe the great extinction at the end of the Permian Period was caused by very high global temperatures combined with a huge volcanic eruption, which belched out clouds of greenhouse gases and raised the temperature yet higher. The first dinosaurs, such as Herrerasaurus, Coelophysis and Plateosaurus, all emerged during the Triassic Period. Pterosaurs, the flying reptiles, such as Eudimorphodon, along with marine reptiles such as Placodus and Nothosaurus, also first appeared during the Triassic.

Triassic world

The world in triassic timesThe world in triassic timesAt the beginning of the Triassic all the Earth's continents were joined together to make the supercontinent of Pangaea. Surrounding this vast landmass was a great ocean, called Panthalassa. As the waters slowly rose and fell, the shape of the coast changed too. So the continents looked very different from what modern maps show. India was far away from the south of Asia, where it lies today. In Triassic times it was situated between Africa and Antarctica.

Reptiles of the Triassic PeriodReptiles of the Triassic Period


A Triassic plant-eater from South America was named Mussaurus, meaning “mouse lizard”—because the first fossil skeleton to be discovered was tiny. Scientists later realized that this skeleton was actually that of a baby. Adults grew to be 3 m (10 ft) long.

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