Octopus
The Octopus is a cephalopod of the order Octopoda. They are invertebrates most closely related to squid and cuttlefish. There are over 200 species of octopuses and they inhabit all of the world's oceans. They prefer shallower waters, especially rocky coasts or coral reefs. Octopuses have no internal bone structure or external shell and so can fit into extremely small cracks and crevices. The only hard part of their bodies is a parrot-like beak located at the bottom of their head, between their eight arms.
An octopus looks like a large domed head sitting on top of an array of swirling arms. Actually this "head" is called the mantle or body and contains all of the octopus's vital organs - including three hearts. The majority of the octopus's nervous system is located in its arms and these are highly flexible and amazingly strong. Each arm has two identical rows of suction cups which not only grab and hold prey, but determine the texture, shape and even taste of the item the octopus is touching. An octopus can regrow arms it has lost. The octopus will use its arms to crawl or swim about, looking for crabs, crayfish, clams and fish.
The octopus is a skilled ambush predator and uses many of its hunting tactics for its own defense. The octopus can squirt a cloud of ink to hide behind, confusing both enemies and prey as to its actual whereabouts. The ink also includes a substance that dulls an attacker's sense of smell. Octopuses prefer to run and hide rather than fight and can shoot concentrated streams of water through their mantle and jet-propel themselves to a quick getaway. They can reach speeds of 25 mph when they do this, but only for very short periods of time. The more preferred way an octopus avoids being eaten is by not being seen. Octopuses have specialized skin cells that change their coloring to perfectly match their surroundings. They can appear to change their skin's texture as well.
The octopus is very intelligent. Scientific experiments have proven they can learn and possess both long-term and short-term memory. Octopuses can negotiate mazes, solve puzzles, distinguish between shapes and patterns and imitate observed behavior. They are notoriously clever at escaping containment and fishermen have found octopuses breaking into the crab holds of their boats to get a meal. In deference to their intelligence, some countries require the octopus be anesthetized before scientists can conduct surgery on them. In the United Kingdom the octopus has been given honorary vertebrate status, extending to this eight-legged cephalopod the same protections against cruelty and neglect that have been extended to other animals.
For all their innovation, intelligence and abilities, octopuses don't live very long. The Common Octopus lives about 2 years, the Giant Pacific Octopus may live for 5 years. Scientists believe the octopus is like the salmon and releases an endocrine secretion that genetically programs them for death after mating. The male usually dies a few months after sending spermatophores down one arm onto the female's mantle cavity. The female lives long enough to lay her eggs and protect them through hatching. She does not eat during this time. She spends her days guarding the 40,000 or so eggs (depending on species), gently blowing water currents over them so the developing fetuses get enough oxygen. The female will live long enough to see her young hatch, but as they rise to the upper waters of the sea to start their lives, she will die.
Fun Octopus Facts
- An adult Octopus can squeeze through a hole the size of a dime.
- An octopus' blood is blue.
- Numerous myths and legends surround the octopus and most of them are false. Octopuses are not aggressive, man-eating or large enough to crush a boat. The largest octopus ever found was 300 lbs with an arm span of 33 feet.
- Octopuses have wonderful eyesight and a complex sense of touch and taste. They are, however, deaf.
- The correct plural of Octopus is octopuses. Octopods is a more scientific term. Octopi is frowned upon.
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