Meet the side-blotched lizard, a cute-looking fellow with scaly splotches all over its body. The lizard comes in three colors, and each color corresponds with a different type of mating behavior for the males. As the video above from KQED’s Deep Look shows, these behaviors have resulted in a millennia-old game of rock-paper-scissors. Each lizard’s skill set helps it defeat males of a specific color, but it also leaves them at a disadvantage against lizards of another other color.

Here’s how it works:

Orange males are the bullies of the species. They collect as many mates as possible and keep them together, using their strength to intimidate and scare the other males away.

Yellows are sneaky, and their modus operandi is to quietly steal a mating partner without being detected.

Blues are monogamous, and once they decide on a mate, that’s the one they’re sticking with.

Orange beats blue because they can overpower the heart-sick lovebirds. Meanwhile, yellow beats orange because orange can’t keep track of all his mates, which leaves him vulnerable to yellow’s sneak attack. Finally, blue beats yellow, because blue side-blotched lizard males are so dedicated, they’d never fall for a smooth criminal like yellow.

This constant game of rock-paper-scissors has kept the males of the species in stasis, and it has been going on for 15 million years. See more in the video above, and check out KQED's story on the side-blotched lizard here.

[h/t KQED]

Banner image: Deep Look, YouTube