That chimpanzees have a close evolutionary relation with human beings is a known fact. But recent research suggests that even our language might have been evolved from the variety of gestures used by chimpanzees to communicate with each other.

A Stirling researcher has identified between 20 and 30 manual gestures used by a community of wild chimpanzees to communicate with others in a range of activities including nursing, feeding, sex, aggression and defence. Interestingly, a third of these gestures could have been used by humans during their evolving stage to develop language.

Postgraduate researcher at the University of Stirling, Dr. Anna Roberts, found that chimpanzees use arm beckoning gestures to make another approach them, flail their arms to make another leave, use begging gestures to make others pass food and clap their hands to express excitement.

The study is the first to show that wild chimpanzees are so close to humans in terms of their communicative abilities and these gestures suggest that the common ancestor of humans and chimpanzees must have used similar manual gestures.

Dr. Roberts said: “Chimpanzees use these gestures intentionally to elicit a desired response from other chimpanzees and they may be the missing link between ape and human communication.” She added: “We now know that these gestures must have been in the repertoire of our common ancestor and might have been the starting point for language evolution. Manual gesture in chimpanzees is controlled by the same brain structures as speech in the human brain.”

Dr. Roberts claimed that chimpanzees not only communicate using manual gestures, but they are able to work out what the signaller means from both gesture and accompanying context.

“Chimpanzees not only use similar manual gestures to humans,” she pointed out, “but the way they use these gestures is also very similar to the way humans gesture and use language. The defining way that people understand communication with others is by figuring out what someone really means by ‘mind-reading’ their intentions and we have discovered that chimpanzees may have a similar ability.”

Dr. Roberts studied chimpanzees in the wild in Uganda over a period of eight months for her PhD at the University of Stirling. The study was undertaken in Budongo Conservation Field Station, funded by the Royal Zoological Society of Scotland.

She has subsequently published two papers: ‘Usage and Comprehension of Manual Gestures in Wild Chimpanzees’ in the journal Animal Behaviour; and ‘Repertoire of Manual Gestures in Wild Chimpanzees’ in Evolution and Human Behaviour .

“We are all interested in what distinguishes us from animals and the defining feature of humans is language. Language allows us to co-operate, to learn from each other and to create cohesive society. No other species has been found to have such a complex and flexible system of communication but we know very little about how we came to have language,” Dr. Roberts said.

Research suggests human language evolved from gestures used by wild chimpanzees