Their great escapes from captivity, too, reflect an awareness of their special circumstances and their ability to adapt to them. He sees that curiosity and opportunism вЂ“ their вЂњmischief and craftвЂќ, as a Roman natural historian put it in the third century AD вЂ“ as characteristic of octopus intelligence. You get a small amount of animals in the lab and some of them refuse to do anything you want them to do вЂ“ theyвЂ™re just too unruly.вЂќ вЂњOctopuses are pretty good at sophisticated kinds of learning, but how good itвЂ™s hard to say, in part because theyвЂ™re so hard to experiment on. вЂњI think itвЂ™s a mistake to look for a single, definitive thing,вЂќ says Godfrey-Smith. ThereвЂ™s no one metric by which to measure intelligence вЂ“ some markers, such as tool use, were settled on simply because they were evident in humans. In captivity, they have learned to navigate simple mazes, solve puzzles and open screw-top jars, while wild animals have been observed stacking rocks to protect the entrances to their dens, and hiding themselves inside coconut shell halves.Д«ut thatвЂ™s also reflective of their dexterity: an animal with fewer than eight legs may accomplish less but not necessarily because it is more stupid. The coconut octopus is one of the few cephalopods known to exhibit the behaviour of using a tool. Half a billion neurons put octopuses close to the range of dogs and their brains are large relative to their size, both of which offer biologists a rough guide to brainpower. This apparent problem-solving ability has led cephalopods (particularly octopuses, because theyвЂ™ve been studied more than squid or cuttlefish) to be recognised as intelligent. Elsewhere octopuses have plugged their tanksвЂ™ outflow valves, causing them to overflow. Godfrey-Smith writes of animals learning to turn off lights by directing jets of water at them, short-circuiting the power supply. Most aquariums that have attempted to keep octopuses have tales to tell of their great escapes вЂ“ even their overnight raids of neighbouring tanks for food. Albert and Bertram performed in a вЂњreasonably consistentвЂќ manner, but one named Charles tried to drag a light suspended above the water into the tank squirted water at anyone who approached and prematurely ended the experiment when he broke the lever. Charming anecdotes like this abound in Godfrey-SmithвЂ™s book, particularly about captive octopuses frustrating scientistsвЂ™ attempts at observation.ДЄ 1959 paper detailed an attempt at the Naples Zoological Station to teach three octopuses to pull and release a lever in exchange for food.

How smart are octopus