Octopus

Octopus

The octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. Around 300 species are recognised, and the order is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Octopuses are among the most intelligent and behaviourally diverse of all invertebrates. They are eaten and considered a delicacy by humans in many parts of the world.

About Octopus in brief

Summary OctopusThe octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. Around 300 species are recognised, and the order is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Octopuses are among the most intelligent and behaviourally diverse of all invertebrates. They are eaten and considered a delicacy by humans in many parts of the world, especially the Mediterranean and the Asian seas. The giant Pacific octopus is often cited as the largest known octopus species. Adults usually weigh around 15 kg, with an arm span of up to 3 m. Much larger giant octopuses have a mass of 71 kg. The largest specimen of this species to be scientifically documented was an animal with a live live mass of 272 kg. A battle with an octopus appears in Victor Hugo’s book Toilers of the Sea, inspiring other works such as Ian Fleming’s Octopussy. The standard pluralised form of \”octopus\” in English is \”octopuses\”; the Ancient Greek plural has also been used historically. The Oxford English Dictionary lists the two forms in that order, reflecting frequency of use. The New Oxford American Dictionary lists “octopi” as the only acceptable pluralisation, and indicates that  “octopodes” is still occasionally used, but that “ octopi’ is incorrect”.

The octopus has a complex nervous system and excellent sight. It is bilaterally symmetric with two eyes and a beak, with its mouth at the center point of the eight limbs. The siphon is used both for respiration and for locomotion, by expelling a jet of water. All species are venomous, but only the blue-ringed octopus are known to be deadly to humans. The male uses a specially adapted arm to deliver a bundle of sperm directly into the female’s mantle cavity, after which he becomes senescent and dies, while the female deposits fertilised eggs in a den and cares for them until they hatch. A carcass of the Haliphronlanticus octopus, at 61cm long, weighs less than 1 g. The smallest species is the Octopus wolfi, which is around 2 cm long and weighs around 5 cm and less than 5cm in weight. The head and anterior end of the animal are one end of an elongated body and function as the head and body of the octopus as well as the function of the head as the animal’s head and an end-of-an-end function. The Octopus Wolfi is one of the smallest species of octopus in the world and is around 5cm long and weighs less than 1 cm in weight. It has an arm-span of 7-9m, with a carcass as large as 7-8m.