Fresh evidence of coloration in ancient animals has been discovered in the 10-million-year-old fossilized remains of a snake.

The colours of many extinct animals, including early birds, reptiles, mammals and amphibians, have been reconstructed through evidence of melanin pigments preserved in fossils. Maria McNamara at University College Cork, Ireland, and her colleagues now report evidence of coloration created by a different type of pigment called a carotenoid, preserved in minerals that replaced the tissues during fossilization.

The team discovered pigment cells, called chromatophores, that would have contained carotenoids and light-reflecting granules in the skin of the fossilized snake, which was discovered near Teruel in Spain. The findings suggest that the animal had a pale belly and a green back and sides, with brown–black and yellow–green blotches — possibly a form of camouflage. The coloration could also have been a way to signal to other snakes.

Curr. Biol. (2016)