Chameleons’ layered emotions

Chameleons are cold-blooded reptiles that come in a variety of colours. The skin has underneath it layers of different coloured cells controlled by nerves and hormones. When it is threatened, a male panther chameleon becomes angry, it changes colour from placid green to angry orange in seconds, and finally to bright red. When both layers of coloured cells contract, white cells are revealed and the skin turns pale.