In a test of short-term memory, young chimpanzees have been proven to be better than adult humans.

Japanese researchers pitted young chimps against college students in a numerical skills challenge and the animals won hands down.

The simple test, according to Kyoto University Tetsuro Matsuzawa, debunks the age-old belief that humans are superior to chimpanzees in all cognitive functions.

In Tuesday's issue of the journal Current Biology, Matsuzawa detailed the results of a test where a dozen human volunteers tried to outsmart three five-year-old chimps, who were taught Arabic numerals from one to nine.

In the first test, all nine numbers projected on a computer screen. When a number is touched, the remaining eight numerals are masked with white blocks.

The contestant that can touch all the squares the fastest in the order of the numbers that used to be there wins.

The researchers found that chimps could do the task with the same accuracy as human, but faster.

But a chimp named Ayumu was a cut above the rest of the chimps. A second test had five numbers flashed on the screen and then masked again with white squares.

Ayumu was able to touch the squares in proper sequence even when the squares were shown very briefly, about two-tenths of a second.

Researchers said the shorter the display time, the lower the accuracy of humans unlike the young chimps whose batting average was constant.

"Our common ancestors might have had immediate memory, but in the course of evolution, they lost this and acquired language-like skills," said Matsuzawa.

So what is the secret to Ayumu's success aside from the fact the evolutionary process was in its favor. According to Matsuzawa, it is his age. He noted Ayumu's mother fared worst that the college contestants.