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The Environment - Why Did Dinosaurs Become Extinct?
Why did dinosaurs become extinct?
There are many theories as to why dinosaurs disappeared from the Earth about 65 million years ago. Scientists are divided between two primary schools of thought on the subject: the gradualists believe that the dinosaurs' extinction was a gradual process, and the catastrophists believe the dinosaurs were wiped out by a single catastrophic event.
The gradualists propose that the dinosaur population steadily declined at the end of the Cretaceous Period (144 to 65 million years ago) for a variety of reasons. Some claim the dinosaurs underwent biological changes which made them less competitive with other organisms, especially the mammals that were just beginning to appear. An alternate theory is that the dinosaurs suffered the effects of overpopulation. A third theory is that mammals drove dinosaurs to extinction by eating dinosaur eggs. Others believe that a variety of diseases...
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Environmental Degradation
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