Raoul Schwing remembers sitting on the top of New Zealand mountain, watching a kea hovering in front of him, just an arm’s reach away. The large green parrot had jumped into an updraft and was flying into the rushing air with such skill that it stayed in precisely the same spot. And then, it made an almost gradual shift in its wings and shot off like a cannon. Keas do this a lot, and since they often hover more than a meter or so off the ground, they’re clearly not doing it for the view. Instead, Schwing says, they’re playing.
That might sound a bit human-like, were it not for, well, everything else about keas. These parrots are famed for their curiosity, intelligence and vivacious nature. They’ll chase each other through the air, do spirals and loops and wheeling side-by-side, before landing in the same spot from which they took off. They’ll toss a rock back and forth, like some kind of parrot tennis. They will sneak up and briefly grab each other by the feet. They’ll wrestle: One kea will jump like a kitten and another will lie on its back.
Activities or play of “limited immediate function,” in the words of the evolutionary psychologist Gordon Burghardt is common in the animal world. Even amphibians, fish and reptiles have been known to do it. But whether it’s to practice adult skills, or to coordinate the development of the growing brain, or to teach an animal how to be flexible in its actions, play tends to peter off during adulthood, and especially between individuals of the opposite sex. African hunting dogs, adult wolves and coyotes will play before a hunt. Bonobos and chimps play with potential mates. But in keas, both juveniles and adults play with each other in positions where neither food nor sex is in the cards.
By studying these birds, Schwing also realized that they have a “play call, a warbling noise that they make while they’re playing. Schwing first became interested in keas four years ago because they’re such different birds. They perch on an ancient branch of the parrot family tree: Around 56 million years of evolution separate them from other parrots like budgies or macaws. They’re very intelligent.
Unlike other birds, which shy away from unfamiliar and new objects, keas are drawn to novelty like moths to a flame. Schwing once determined this by asking one of his colleagues at the University of Vienna to shine a bicycle light at some captive ravens. Even though he had hand-raised those birds, they fled when the light came on. But when he did the same to confined keas, half the birds immediately flew over to investigate. Schwing said, “This makes them very easy to study in the wild. For most birds, you need hides and blinds.”