Chameleons, famous for shifting colors to blend into their natural surroundings to avoid predators, may also be using their chromatic superpowers for a totally different reason: To win fights.
According to researchers at Arizona State University, chameleons change color when preparing to fight one another. They use this skill to intimidate opponents — often to the point where the winner is predetermined and the altercation avoided altogether:
When male chameleons challenge each other for territory or a female, their coloring becomes brighter and much more intense. Males that display brighter stripes when they are aggressive are more likely to approach their opponent, and those that achieve brighter head colors are more likely to win fights. Also, how quickly their heads change color is an important predictor of which chameleon will win a skirmish.
In order to figure all this out, scientists set up a chameleon fight club, really. New Scientist reports:
To see if individual variations in these colors and patterns influenced the outcome of a fight, [researcher Russell] Ligon and his colleague Kevin McGraw staged a round-robin tournament in which 10 male veiled chameleons were pitted against each other.
Not all fights were preemptively resolved by the shift in hue, as you can see from the following video, which is set to dramatic music for ultimate viewing pleasure.
Chameleons show each other their sides before battling - so if a brightly colored chameleon flashes its side at another, the targeted chameleon may opt to back off the aggressor. If, however, the target still wants to participate he can see if the aggressor's head is changing color before deciding whether to engage in a "head-butting, biting, shoving contest."
Researchers say males can also use their colors to demonstrate value to potential mates, a la the peacock.