Saturday, February 16, 2013
Chimpanzees can far outperform humans in some mental tasks, including rapidly memorizing and recalling numbers, Japanese scientists have shown
At the American Association for the Advancement of Science annual meeting, Tetsuro Matsuzawa, of Kyoto University’s Primate Research Institute, showed remarkable videos of chimpanzees displaying mental dexterity that would be way beyond most people. The star performer among the institute’s 14 chimpanzees, a 12-year-old male called Ayumu, has learnt all the numerals from 1 to 19. Several other Kyoto chimpanzees have learnt 1 to 9. When the numbers flash up in random places across a computer screen and in random order, and disappear after less than a second, the apes can point immediately to the exact locations where the numerals had been, in the correct numerical order. Matsuzawa said that a few exceptional people, such as those with savant syndrome, might be capable of such memory feats but they are far beyond the average human brain. “One person in several thousand may be able to do this,” he said. “All the chimps I have tested can do it.” Matsuzawa, who combines the study of wild chimpanzees in west Africa with research using the captive colony in Kyoto, said that such a good working memory – the ability to take in an accurate, detailed image of a complex scene or pattern – was an important survival tool in the wild. For example, the apes can quickly assess and remember the distribution of edible fruit in a forest canopy. Or, when two rival bands of chimpanzees encounter one another, they can assess the strength of the rival group and decide whether to fight or flee.