It's a rare occurrence for scientists to witness sharks mating in the wild. It's even rarer to catch three leopard sharks—two males and one female—engaging in what amounts to a threesome in the wild on camera, particularly since they are considered an endangered species. But that's just what one enterprising marine biology team achieved, describing the mating sequence in careful, clinical detail in a paper published in the Journal of Ethology.

It's not like scientists don't know anything about leopard shark mating behavior; rather, most of that knowledge comes from studying the sharks in captivity. Whether the behavior is identical in the wild is an open question because there hadn't been any documented observations of leopard shark mating practices in the wild—until now.