Can animals be creative? In our last blog, we told the story of the boy who told the story of the cat who learned to play the piano. There is at least one such cat, whom you can watch on YouTube (website below). Whether this particular cat is creative just because it paws the piano is debatable. But what if you could demonstrate that an animal not only invented a new behavior, but that other animals copied it? And what if this behavior was then modified and transformed to solve yet another problem?

In 1953, on a small island off the coast of Japan, scientists began observing macaques to compare their behaviors with those of other primates. In order to habituate the shy macaques to their presence, the primatologists provisioned the animals with sweet potatoes, dropping them on the ground. By and large, this meant that the macaques were served their potatoes à la grit. Then one day, a young female macaque, whom the researchers called Imo, carried a dirty sweet potato into a fresh-water stream and dipped it in the water. She soon took to wetting and rubbing clean all her potatoes before eating them.

Almost everything about this observed behavior fits the standard definition of creativity as ‘effective novelty’. No primatologist had ever seen a macaque wash potatoes before. Certainly no other macaque in her troop was washing potatoes at the time Imo began doing so. Imo seems to have invented the novelty herself. Her behavior was also effective: no more grinding teeth on sandy soil.

But the story doesn’t end there. Cognitive scientists also distinguish creativity from innovation. Creativity can be personal, like the cat who plays the piano: the novelty’s only effectiveness may be some kind of personal pleasure. Innovation requires that what is invented is, in economic terms, “brought to market.” Innovations are socially creative; they change the way groups think and act.

Imo’s invention was also an innovation. Within a few months, Imo’s brothers and sisters, some of her friends, and her mother, too, were washing their potatoes. The behavior slowly spread to other young macaques, their older siblings and their mothers. Only the “Old Guard” males remained aloof, perhaps because they spent less time interacting with the troop as a whole. Within five years, some three-quarters of the macaques on the island were regularly washing their potatoes before eating. Indeed, fifty years later, well after the death of Imo and that first generation of potato-washers, the macaques off the coast of Japan continue to clean their potatoes by dipping and rubbing them in water -- though they now wash their potatoes in the sea, perhaps for the enhanced flavor.

Behavioral innovations in macaques and other primates are rare. Probably not more than a few dozen have been recorded all around the world, let alone observed at initiation. So what are the chances that a single individual would launch two? Well, Imo did! Three years after she began washing potatoes, Imo initiated a second innovation. Scientists also provisioned the macaques with wheat, dumped on the ground. One day Imo was observed tossing handfuls of sandy wheat in the water, effectively separating the wheat (which sank very slowly) from the not-so-proverbial sandy chaff (which sank very quickly). Like potato-washing, this sluicing of sandy wheat also spread among Imo’s group of macaques. Macaques appear to prefer their wheat, like their potatoes, sans sand.

One could, of course, object that the wheat sluicing invention was just another form of potato washing. Imo washed potatoes, so why not wheat? But if it was that obvious, why did none of the other macaques make that mental leap? One reason may be that it is not at all obvious, even to a human being, that potatoes are analogous to wheat. Their differences are much more evident than their similarities. And even if you are smart enough to categorize both potatoes and wheat within the common category of ‘food’ -- an intellectual accomplishment that may give young children pause -- there are distinct problems posed by washing and retrieving tiny grains of wheat that do not pertain to potatoes! Accident or not, to wash wheat free of sand requires additional creativity in handling the food.

We think Imo was a creative animal genius! And if we look for them, who knows how many more may be found in the wild. What do you think?

© Michele and Robert Root-Bernstein 2012

For other animal innovations, see Frans DeWaal, The Ape and the Sushi Master (Basic Books, 2001) and James Bonner, The Evolution of Culture in Animals (Princeton University Press, 1980).

For Nora the piano-playing cat, see