Cephalopods (class Cephalopoda) are the most advanced class of molluscs and rank amongst the most sophisticated of all invertebrates. They include the largest invertebrates known, the giant squids, which reach a length of 20 m.
Many have reduced shells to an internal flotation device or a thin internal skeleton. Octopuses have virtually lost their shell. The head and foot are merged, and the foot is divided into 8 or 10 arms with suckers. The mouth lies between the arms and has a strong parrot-like beak that tears into the prey and may inject a toxin. No Southern African species are dangerous to humans, but one Australian species is lethal. The mantle that covers the gut and gonads forms a sheath into which water is drawn and then forcefully expelled, jetting the animal backwards.
In prehistoric times, the ancestors of squid and cuttlefish dominated the seas. Even today, the abundance of squids gas made them a target for commercial fisheries.
F*CK FISH 