Scientists in Japan are excited these days about a bright chimp named Ai, which is Japanese for "love." The 23-year-old primate is skilled at using a computer, but even more amazing is her power of memory, which is said to be on a par with an adult human's.

Researchers have designed computer programs to test chimpanzees' ability to recognize symbols, such as Japanese characters, numbers, and other figures. Many of the animals used in experiments have been able to recognize shapes and tell them apart, but Ai is the first to memorize long series of numbers--as many as five digits in a row.

For most human beings, a seven-digit series of numbers is about the longest they can memorize after hearing it once. This puts Ai very close to people in terms of her ability. According to Professor Tetsuro Matsuzawa of Kyoto University's Primate Research Institute, she has also shown an understanding of the concept of the number zero--pretty complicated stuff for a chimp. (You can learn more about Professor Matsuzawa's project and see video of Ai's experiments here.)

Ai has become famous throughout Japan for her intelligence. She came to the country from Africa in 1978, when she was one year old, and Matsuzawa began studying her that year. There are 10 other chimpanzees at the Primate Research Institute, all of whom study on computers every day. But Ai is far and away the brightest of the lot. She can recognize about 100 symbols in all--including numerals, Japanese characters, and images representing different concepts--and she can even grasp the meaning of "sentences" put together with these symbols.

Recent studies have shown that humans and chimpanzees share a common ancestor, and that the two branches of the family tree split about 5 million years ago. Being closely related to us, chimpanzees are able to do things like use tools and understand abstract symbols--tasks that only humans were thought to be capable of. Ai and her companions are helping to change that thinking.

Ai is pregnant now, and is expecting a baby in April. Matsuzawa is preparing to move on to the next phase in his study, in which he will observe how Ai teaches what she has learned to her child. Until now we have thought that only humans passed on abstract information to our young, but perhaps Ai will prove us wrong once again!

Photo: Ai memories the location of five numbers in a flash and taps them out in order. (Jiji)