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At their peak, how many dinosaurs roamed Earth? © Getty Images

At their peak, how many dinosaurs roamed Earth?

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It's difficult to calculate the exact populations of these large reptiles based on our limited fossil record, but there are some factors we can look at.

Asked by: Graham Roe, Lancashire


There are around a thousand different genera of dinosaurs known. We can’t directly measure the size of populations because we don’t know what percentage of individuals are preserved in the fossil record. Twenty million bison roamed America in the 18th Century and dinosaurs, being egg layers, could have reproduced faster. Assuming that the availability of plants was the limiting factor, large dinosaurs probably reached comparable population sizes in the Jurassic, 60 million years ago.

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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.


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