The more we know about animal cognition, however, the more examples like Ayumu’s are coming to light. For example, apes solve the inaccessible peanut task better than many human children. In this task, an ape faces a peanut placed at the bottom of a vertical transparent tube. Liza, a female chimp at the Yerkes Primate Center’s field station, in Georgia, solved it right away. After some vigorous but ineffective kicking and shaking of the tube, she abruptly turned around, went to the faucet to fill her mouth, and returned to the tube to add water. She made several more trips to the faucet before she got the peanut at the right level to reach it with her fingers. Another female tried to pee into the tube! She had the right idea even though the execution was flawed. I have known Liza all her life and am sure that this problem was brand new to her. How hard this task is is clear from tests on children, many of whom never find the solution. Less than 10 percent of 4-year-olds come up with it, and only about half of the 8-year-olds. Most children frantically try to reach the prize with their fingers, then give up.
In another striking example at the Kyoto institute, separate computer screens were set up for two apes. They played a competitive game that required them to anticipate one another’s moves, a bit like a rock-paper-scissors game. Could they outguess their rival based on his or her previous choices? The performance of the apes was compared with that of humans playing the same game. The chimps won, reaching optimal performance more quickly and completely than members of our own species. The scientists attributed the apes’ edge to them being quicker at predicting a rival’s moves and countermoves.