Monks from the order would toss the potatoes onto a beach, and the monkeys would scarf them down, sand and all. But one day a female monkey took her sweet potatoes to a nearby stream, dunked them in the water and washed off the gritty sand. Over the course of several years the others followed, first the youngsters, then the females, and finally the old men of the colony.
Other experimenters, notably researchers at the Yerkes National Primate Research Center of Emory University, have shown that chimps can learn by watching other chimps that have been taught by humans how to use a tool to retrieve food. In time, all the chimps were doing it, so it had become part of their culture, to be passed on to others.
Scientists point out that none of the animals is actually teaching the others how to do something. Instead, animals are learning by simply observing others who have been successful at doing something, usually getting food.
What is different about Noonan's work, however, is it involves something that is rare in the animal world. The orcas in the aquatic park had learned how to set a trap, and that knowledge had been acquired by other members of the pod.
Their culture had expanded, as well as their diet, through a bit of clever innovation that eventually was shared by all.