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what is fins in fish

Fins are the most distinctive features of a fish. A fish's fins have many functions. Fish have several fins, and what they do with them depends on their species. Some fins are used purely for decoration or to attract a mate, but most have more practical functions. It is composed of bony spines protruding from the body with skin covering them and joining them together, either in a webbed fashion, as seen in most bony fish, or more similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fins have no direct connection with the spine and are supported by muscles only. Fins are used for swimming and sometimes for protection. Some fins are paired and others unpaired. The paired fins are the pectoral and pelvic fins. The unpaired fins are the dorsal, caudal (tail) and anal fins. The way the fins are used varies among different groups of fish. Most fish use their tails to move through the water and their other fins to steer with.Fins are most bony fish are flexible and supported by visible spines and rays.The shape, location and size of a fish's fins are closely linked with its way of life.

Different types of fins are:

·         Dorsal fins are found on the back of the fish. There may be up to three of them. The fish uses this fin for balance in the water and sudden movements.

·         Caudal fins are also known as tail fins. This is what we refer to as the fish’s tail.

·         Anal fins are on the ventral (bottom) surface of the fish, behind the anus. Fish use these for stability while swimming.

·         Pectoral fins are located on each side of the fish, around where the head meets the body. These are often thought of as the fish’s “arms”.

·         Pelvic fins are located on each side of the fish, near it’s bottom middle. These help the fish go up and down as well as turn sharply in the water.

·         Adipose fins are soft fins found between the dorsal and caudal fins, usually closer to the caudal fin.

·         Caudal keels are small horizontal fins just forward the caudal fin on each side of the fish. You’ll find these on faster swimming fish.

·         Finlets are small fins that look like ridges along the top and bottom of the fish, behind the dorsal and anal fins.