We all know that chameleons change colors. They do this to hide from predators. Males do it to attract a mate and in contests with other males. But HOW chameleons change color has been a bit of a mystery until now.
A team of researchers at the University of Geneva in Switzerland used several high tech methods to figure it out. The scientists combined electron microscopy, videography and optical modeling to figure out how chameleons change colors during social interactions.
The findings are published in the March issue of Natural Communications.
The scientists say panther chameleons (Furcifer pardalis) change their colors by tuning guanine nanocrystals within their skin. By changing the spacing between these nanocrystals, the chameleons can alter which wavelengths of light their skin absorbs and reflects.
The organization of iridophores into two superposed layers is an original evolutionary development for chameleons that allows some species to combine efficient camouflage with spectacular display.
It is also believed this provides some species of chameleon with some level of protection from thermal radiation.
Video and photos courtesy Teyssier, J. et al. Photonic crystals cause active colour change in chameleons. Nat. Commun. 6:6368 doi: 10.1038/ncomms7368 (2015)