Passage II

For Octopuses, Play's the Thing

Often dismissed as aquatic oddities, the octopus is part of a species that are among the most intelligent animals on Earth. With the largest brains of any invertebrate, octopuses can solve complex problems. Researchers have documented octopuses navigating intricate mazes and octopuses even open screw-top Jars.

In 2012, at the New England Aquarium, an octopus used its anatomical siphon to propel a pill bottle crossed its tank. When the pill bottle reached the other side, a jet stream in the tank returned it to the octopus. Amazingly, the octopus propelled the pill bottle back toward the jet stream. The researchers at the aquarium realized the octopus was doing something extraordinary: inventing a version of pitch-and-catch.

In inventing this game, the actions of the octopus were not based on survival. The octopus simply wanted to play. Evolutionary biologists believe play could have an important role through animals cognitive development. According to the Theory of Flexibility, play, the theory says, teaches an animal to modify its behaviors, helping the animal prepare for unexpected situations.

Embracing this idea, researchers at Cincinnati's Newport Aquarium have compiled an"Octopus Enrichment Handbook." Crazy, right? Yet this book provides in-depth descriptions of toys and puzzles researchers have invented for octopuses. One such puzzle is a series of nesting cubes. Each cube features a different latch for the octopus has to open until the octopus reaches the smallest cube. Typically, after just a few weeks, octopuses master this puzzle, solving it in a matter of minutes.(26)

Researchers are interested not only in whether octopuses can solve such puzzles but also in the methods by which they do so. While one octopus might use trial-and-error to unlatch the cubes, another octopus may just use a lot of strength in opening the larger cubes to get to the smaller ones. Therefore, researchers have noted how octopuses modify and improve their methods over time, suggesting that play may indeed be a factor in an octopus's cognitive development.