Kings of Camouflage (PBS NOVA)

Cuttlefish are marine animals of the order Sepiida. They belong to the class Cephalopoda, which also includes squid, octopi, and nautiluses. 'Cuttle' is a reference to their unique internal shell, the cuttlebone. Despite their name, cuttlefish are true molluscs.

Cuttlefish, although color-blind, are able to change the color of their skin. The chromatophores are elastic sacs containing different pigments. Bands of muscle radiate from each chromatophore and are controlled by neurons from the motor centres in the brain. The cuttlefish can control the contraction and relaxation of the muscles around individual chromatophores, thereby opening or closing the elastic sacs and allowing different levels of pigment to emerge. This allows the cuttlefish to change its color at will to match its background for camouflage. (wikipedia.org)

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