We've always been told that chameleons change color to camouflage themselves and blend in with their background. Well, according to scientists at the University of Melbourne, Australia, that was wrong: chameleons evolved the ability to change colors to make themselves more noticeable to other chameleons.
As chameleons have a different visual system to humans, they have a fourth type of cone which is ultra-violet (UV) sensitive, the researchers had to first measure what the chameleons were actually seeing.
The Melbourne-based researcher explained: "We measured colour with a spectrometer, which measures both the UV and visual colour range, and combined this with information on the chameleon visual system to model chameleon colour perception." [...]
Co-author Dr Devi Stuart-Fox, from The University of Melbourne, Australia, told BBC News: "[Our research] suggests that chameleons evolved colour change for signalling, to fend off rivals or attract a mate, and not so they could match a greater variety of backgrounds."