The mysterious sex lives of dinosaurs

Updated 4:20 AM ET, Mon September 20, 2021

Science has transformed our understanding of dinosaurs in the past two decades. Get caught up with what's new in this five-part CNN series.

(CNN)Dinosaurs must have had sex to reproduce but how they did it -- with their neck frills, armored plates and tails tipped with spikes -- isn't exactly clear.

No fossil has revealed two dinosaurs caught in the act -- the only known vertebrates to be unequivocally preserved mating are a pair of 47 million-year-old turtles that were attached by their genitals as they got buried alive.
It's also not possible to easily determine whether a dinosaur is male or female from fossilized bones.
Fossils that preserve elements of dinosaur behavior are very rare. However, with close analysis and insights from what we know about living animals, particularly birds, paleontologists are beginning to piece together the sex lives of dinosaurs.
The oldest known vertebrates to be fossilized while mating are a pair of 47 million-year-old turtles, which were attached by their genitals as they got buried alive.

Sex differences