Cephalopods behave in ways that certainly suggest they’re highly intelligent. An octopus named Inky, for example, made a notorious escape recently from the National Aquarium of New Zealand, exiting his enclosure and slithering into a floor drain and, apparently, out to sea. BrainBook/Task/Material
The most famous octopus tales involve escape and thievery, in which roving aquarium octopuses raid neighboring tanks at night for food. Those stories—the basis for octopod hijinks in the 2016 Disney-Pixar film Finding Dory—are not especially indicative of high intelligence. Neighboring tanks are not so different from tide pools, even if the entrance and exit take more effort. But here is a behavior I find more intriguing: in at least two aquariums, octopuses have learned to turn off the lights by squirting jets of water at the bulbs and short-circuiting the power supply. At the University of Otago in New Zealand, this game became so expensive that the octopus had to be released back to the wild. BrainBook/Task/Material