"They dominated our planet for 130 million years. You can't do that without having babies, and to have babies, dinosaurs had to have sex. The mystery is—and this is still very much a mystery—we don't really know how they did it.
The key problems being:
First, dinosaur ladies and dinosaur gentlemen were roughly the same size. No big/little asymmetry as with spiders. With spiders, the little fellow mounts the big lady. There are no body-crushing weight issues.
Second, dinosaurs often had huge tails right above where the opening would be. What do you do with those tails? Where do you put them that's out of the way? They're huge.
And third, some dinosaurs are covered with spikes, plates and barbs. So it's the porcupine problem: How do you make contact without getting hurt?
In his book My Beloved Brontosaurus, Brian Switek considers all these questions, and I find the details fascinating . . ."
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