Octopus | 水產百科網

Octopusaresoft-bodied,eight-limbedmolluscsoftheorderOctopodaTheorderconsistsofsome300speciesandisgroupedwithintheclassCephalopodawith​ ...

Soft-bodied eight-limbed order of molluscs

An octopus (PL: octopuses or octopodes, see below for variants) is a soft-bodied, eight-limbed mollusc of the order Octopoda (, ok-TOP-ə-də[3]). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the center point of the eight limbs.[a] The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates.

Octopuses inhabit various regions of the ocean, inc...