Hobbies And Interests
Octopus Dens
Like many terrestrial animals, octopuses maintain dens where they can avoid predators and lay eggs. Unlike many other mollusks, octopuses lack shells, so they can squeeze their soft, boneless bodies into a variety of small spaces. An octopus might make its den under a rock ledge, in a crevasse or in a flowerpot or other manmade object that has made its way to the sea floor.
Camouflage
Even the giant Pacific octopus has to evade predators such as seals, otters and sperm whales. To avoid becoming dinner, an octopus can change color, blend into the sea floor or disguise itself as another aquatic animal, such as a sea snake, by assuming a certain posture or mimicking a texture. Octopuses also change colors as a mating display and as a warning signal.
Eating Habits
Octopuses can eat a variety of other animals, including crustaceans, mollusks, fish and even birds. They have a special organ, the salivary papilla, that can break through the shells of mollusks or crustaceans. Octopuses also have hard beaks and a radula or rough tongue, which they use to bite through and scrape up prey. The suckers on their tentacles help them hold on to prey as they eat.
Octopus Anatomy
Most other invertebrates -- such as insects and lobsters -- have simple brains, but with an estimated 300 million neurons, octopuses have the most complex brains of any invertebrate; they can learn and remember. They also have eyes that are very much like those of vertebrates, though octopuses focus light differently than vertebrates. Octopuses' eyes are also different from vertebrate eyes in that they have no blind spots.