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Octopuses

A blue-ringed octopus, Pacific and Indian oceans, up to 20 cm (8 inches). It is one of the most venomous of all marine creatures,...Read More >>A blue-ringed octopus, Pacific and Indian oceans, up to 20 cm (8 inches). It is one of the most venomous of all marine creatures, with a bite fatal to humans. Octopuses belong to a family of molluscs called cephalopods, a group which also includes squid, cuttlefish and nautiluses. They have bag-shaped bodies and eight arms. Octopuses live in all of the world’s seas and oceans. The smallest species are only the size of a fingernail, while the largest have an arm span of up to 9 metres (30 feet). Octopuses use their sucker-covered arms to clamber around the seabed and seize their prey of crabs and lobsters. They have large eyes and excellent eyesight, the best of any invertebrate. Like humans, they can see in colour, which many other sea creatures cannot. Octopuses are considered the most intelligent of all invertebrates.



Arms

Pacific octopus gripping its prey, a crabOctopuses have eight muscular arms used for gripping, touching, fighting and walking along the seabed. Suckers along the underside of these arms help them to grip prey and force it into their beak-like mouth.
 

Octopus comes from the Greek word, oktapous, meaning "eight-footed".

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