octopus
The name of the octopus comes from a Greek word meaning “eight-footed,” and this sea creature is distinguished by its eight tentacles. They are usually called arms. The octopus is a soft-bodied animal known as a mollusk and is related to the squid. There are more than 150 types of octopuses, and they are found in seas throughout the world. Most are harmless.
The typical octopus has a baglike body and large eyes. The eight long, slender arms reach out in all directions. Each arm has two rows of fleshy suckers that have a great holding power. The arms are joined to the body by a web of tissue known as the skirt. At the center of the skirt lies the mouth. The mouth has a pair of sharp, horny beaks and a filelike organ called the radula. These features are used for drilling shells and tearing away flesh.
Octopuses vary greatly in size. The smallest are about 2 inches (5 centimeters) long. The largest may grow to 18 feet (5.5 meters) in length and have an armspan of almost 30 feet (9 meters). The octopus can change its color quickly depending on its surroundings. It does this by varying the pigment, or the coloring substance, in its skin.
The octopus crawls along the ocean bottom on its arms searching for its favorite foods. Octopuses are skillful hunters. They eat mainly crabs and lobsters, but they also attack large prey such as sharks. They are thought to be highly intelligent creatures.
The octopus takes in water and then gets rid of it through a funnel. It also squirts water and moves quickly when alarmed. When threatened, the octopus ejects a dark inky fluid to protect itself and confuse the enemy. The fluid produced by some types of octopuses can paralyze the sensory organs of the attacker.
The common octopus mates during the winter. The female lays her eggs under rocks or in holes. She guards the eggs for four to eight weeks until they hatch.
