The dinosaur's derrière is so well preserved, researchers could see the remnants of two small bulges by its "back door," which might have housed musky scent glands that the reptile possibly used during courtship — an anatomical quirk also seen in living crocodilians, said scientists who studied the specimen.

How do you know they weren't testicles? I wonder if it's possible that dinosaurs started out with external testes that migrated inward as the climate cooled.

None of the reproductive soft tissues (like a penis) were preserved. So the researchers can't say whether the dinosaur was male or female. Even so, this dinosaur likely had copulatory sex, unlike some birds that bump butts when they do a "cloacal kiss" during reproduction, Vinther said.

Why? Too big? Body the wrong shape? Not flexible enough? I'm actually curious about this. It's been a question I've had for a long time but I feel like I never get a satisfactory answer. I know a lot of paleontology is guesswork based on extant/recently extinct species, and that a lot of the guesses involve "cloacal kissing" due to the fact that most birds and many reptiles reproduce that way. However, theropods, the seemingly most likely candidate for the "cloacal kissing" route due to their suspected relationship with modern birds, had ridiculously big tails which were likely feathered. To me, that raises the question of whether or not theropods truly started the tradition of "raising tail" among birds, or if they were more like ducks but reduced tail size made obscenely large, prehensile penises obsolete because they could go cloac-to-cloac. The tails seem like they'd be too big to "go cloac-to-cloac".

Also, since I did a quick Google search to try and find the answer before posting, here is some dino porn, courtesy of the BBC

Hot theropods in your area!

Big Sauropod Rails Scaley MILF