many (see text), examples:|
Cuttlefish have an internal shell, large eyes, and ten arms furnished with denticulated suckers, by means of which it secures its prey. The name is sometimes applied to dibranchiate cephalopods generally.
Cuttlefish are caught for food, though squid is more popular. They are probably best known today for the shoehorn shaped piece of tough material given to parakeets as a bill-sharpener. Called the cuttlebone, it is composed of calcium carbonate and is porous to provide the cuttlefish with buoyancy.
Cuttlefish are sometimes called the chameleon of the sea because of their remarkable ability to rapidly alter their skin color. Their skin flashes a fast-changing pattern as communication to other individual of the same species, as well as serving as camoflague from predators.