Octopuses are the most remarkably propelled of every last trace of the mollusks. Most octopuses live on the sea floor where they hunt live prey, but some kinds are specialized swimmers found in the deep sea.
Octopuses are relatives of squids, and have much in common with them. Both exist just in the ocean, both have soft figures, both have suckered tentacles for handling prey, and both have a horny snout to slash up sustenance. Octopus eyes are similar in design to our own. Octopuses also have big brains. In fact, they are probably the most intelligent invertebrates. In captivity they quickly learn new tricks, such as unscrewing the lid of a jar to get at food inside. They are not sociable animals, though—most prefer to live on their own.
