Octopuses are amazing creatures. They have no bones, and therefore can go almost anywhere they want. Even a very large octopus weighing 600 pounds can squeeze into a passageway no larger than a quarter. Octopuses don't have air bladders or gas pockets that could implode at great depths, so they can live at the very bottom of the ocean. They have suction cups on their arms to help them grab onto food. We know a lot about octopuses, but we still don't know everything.