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What is a Squid?
The squid, like the octopus and the cuttlefish, can discharge a dark inklike fluid into the water to hide its whereabouts.
One interesting species of squid is phosphorescent, which means it emits light.
Another squid, called "flying squid" are able to leap across the surface of the water.
A squid is any of a large number of marine animals that have a cylindrical body and ten slender arms studded with adhesive suckers.
Squids are invertebrates, or animals without a backbone. Their body is supported by firm cartilages and also, in some kinds, by the remains of a shell hidden deep inside the body. Although some squids grow only 2 inches long, others usually range in length from 1 foot to 3 feet and are sought by fishermen as food or as fish bait. The body of a giant squid may be 20 feet long, with its arms extending an additional 30 feet. It is the largest of all invertebrates.
The tapered body of the squid is adapted for traveling through water. Using its long muscular fins, the squid can move backward, forward, turn sharply, or hover in place. It can also propel itself rapidly backward by forcing a jet of water out through its siphon.
All squids are predators, swimming after and catching fishes of many kinds. The squid swims forward, upward, or downward by graceful movements of a lengthwise fin along each side of the body. To escape from danger, it swims backward, in a form of jet propulsion, by expelling water through a small nozzle located just below its head. Usually the squid also discharges a brownish-black secretion, often called ink. The ink both clouds the water and dulls the sense of smell in fishes that pursue squids by scent.