Chameleons evolved their famous skin-altering abilities not for camouflage but to communicate quickly with others, a new study suggests.
Scientists have known that the reptiles use color-changing for a variety of purposes: to blend in to the environment, to regulate their body heat, and to send messages to other chameleons.
Instead of vocalizing or using pheromones, chameleons communicate visually by changing the colors and patterns of their skin. Different colors and patterns mean different things—similar to how the colors of a traffic light direct drivers.
For example, the brighter colors a male displays, the more dominant he is. So male chameleons can attract a mate or defend their territory by flashing bright colors to each other. To communicate submission or surrender, a male will display drab browns and grays.
Females also use a colorful version of signaling to communicate when they want to reject mates or are pregnant.
But how these traits evolved remained a mystery—until now.
Cephalopods and chameleons. Talk about convergent evolution!