It is unknown how Stegosaurus' were able to mate without hurting each other with their spiky backs.

Looking at it's prickly backs, it’s hard to believe that the Stegosaurus didn’t go extinct sooner. Both the male Stegosaurus and the female are very well armored and it is difficult for either to mount on top of the other. Scientists are not completely certain as to how how the Stegosaurus got freaky.

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