The #1 source for news about monkeys and apes

[Josh Greenman <josh.greenman AT gmail.com>]

http://www.newscientist.com/blogs/shortsharpscience/2009/02/still-dumber-than-a-chimpanzee-1.html

Still dumber than a chimpanzee

February 13, 2009 6:39 PM

Chimpanzees are even smarter than humans than previously thought -- at
least at memorizing numbers.

A cunning eight-year old chimpanzee named Ayumu can memorize a brief
flash of up to eight numerals on a computer screen, according to new
research presented at the American Association for the Advancement of
Science today. Humans who practice the task max out at six numbers,
says Tetusuro Matsuzawa, a primatologist at Kyoto University in Japan,
who trained Ayumu and 13 other gifted chimps.

"Not many people are happy to see that chimps are better than us," he says.

In the test, chimpanzees and humans see a flash of numerals on a
computer screen that quickly become whited out. To perform the task
correctly, you must tap on the non-concealed numbers in ascending
order.

Matusazwa's team previously showed
(http://www.newscientist.com/article/mg19025551.400-when-chimps-outsmart-humans.html)
that Ayumu outperforms humans when six numbers are displayed for two
tenths of a second. But critics suggested that extra practice may have
skewed that result in favour of Ayumu.

To counter such criticism, he has continued training chimpanzees, as
well as humans, on memorizing more and more numbers for shorter
periods of time.

The differences proved even starker when subjects had to memorize
seven or eight numerals. Humans failed nearly every go, while Ayumu's
accuracy never fell below 40 percent.

This ability could help young chimpanzees quickly determine which
trees have the most fruit, while also keeping an eye on their
superiors, Matsuzawa theories. Perhaps human ancestors lost this
capacity while devoting their brains to other tasks, such as language
and communication.

He's now training Ayumu to recall 9 digits.

See how you do against Ayumu with this game
(http://games.lumosity.com/chimp.html).