Two baboons have amazed scientists with their technical abilities and, using computers, demonstrated previously undetected powers of abstract thought.

According to researchers, the discovery may have "profound implications for the evolution of human intelligence and the stuff that separates homo sapiens from other animals."

Two baboons, trained to use computers, were set the task of matching images displayed on the screen by using a joystick.

The researchers familiarised the baboons with a screen display of 16 different little pictures and with a display of the same little picture repeated 16 times.

They then presented the baboons with a series of choices of two new displays. In each choice, one display was a grid with 16 different icons, the other was a grid with 16 identical icons.

Scientists rewarded the baboons for selecting, from two choices, the array that showed the same relationships among pictures as the sample.

Apparently the baboons demonstrated that they were able to perceive "sameness" even when its cues were subtle and abstract. Figuring out a solution required analogical (this is to this as that is to that) reasoning, which many theorists view as the foundation of human reasoning and intelligence.

Results concluded that the baboons learnt to match the grids at a rate greater than chance. It took thousands of trials for them to learn the "relation between relations" required by the task, but they did it.

The research was conducted by Joel Fagot, of the Centre for Research in Cognitive Neuroscience in Marseille, and Edward Wasserman, of both the Centre for Research in Cognitive Neuroscience and the University of Iowa.

"Although discriminating the relation between relations may not be an intellectual forte of baboons, it is nevertheless within their ken," the researchers said.

Fagot and Wasserman also discovered that baboons and humans have different cut-off points for discerning "same" objects. The report's authors speculate that language may play a role, because our verbal expression for "same" makes the idea of "same" more restrictive. In other words, things really have to be identical to qualify.

But to baboons, the authors suggest, the concept of "same" might be fuzzier and more inclusive.

However, the discovery of a baboon's ability to abstract opens the door to other species' cognitive potential, they said.