Though dinosaurs are hundreds of times the size of birds, their sex lives may not have been that different from their modern-day descendants, scientists with dinosaur sex on the brain suggest.
While it's difficult to really know what happened when dinosaurs got down and dirty, they make some educated guesses based on dinosaur anatomy and the mating habits of birds, the Huffington Post says:
The males and females of modern-day birds and reptiles have a single body opening for urination, defecation, and reproduction--something called a cloaca (Latin for sewer). Paleontologists believe that dinosaurs had the same basic equipment, and that they coupled by pressing their cloacas together.
Some dinosaurs may have had penises or similar organs, but researchers can't be sure since soft tissue (ha ha!) isn't preserved in fossils. If T. Rex had a penis, it could have been up to 12 feet in length. The male would have mounted from behind and to line his cloaca up with the female's.
"I don't think there's much doubt about that," Dr. Gregory M. Erickson, an evolutionary biologist at Florida State University, told The Huffington Post in a telephone interview. But, he acknowledged, "It must have been a hell of a thing to see."
Click through to the Huffington Post for a slideshow of images and videos of dinosaurs getting it on. BuzzFeed also has a nice collection of dinosaur porn. Also, check the video below for Titanosaur sex in explicit detail, from the Discovery Channel's 2010 special "Tyranosaurus Sex."