What Happened to the Dinosaurs?

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Dinosaurs appeared on Earth about 225 million years ago. But there are no living dinosaurs today. They seem to have become extinct at the end of the Cretaceous Period, about 65 million years ago. It is quite
possible that the plants they ate died out. Or maybe a comet or meteorite hit the Earth, causing an explosion that threw clouds of

dust into the atmosphere. The dust blotted out the Sun, plants died and so did the dinosaurs.

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