Of all of the worlds species, humans and chimpanzees are among the few to engage in co-ordinated attacks on rival members. Photo: Chris Collingridge/The Star

London - To many of us chimpanzees appear rather cuddly animals. They do, however, share with humans one of our least attractive traits – the drive to wage war.

In fact, chimps are inherently violent, says a study which suggests waging war has deep evolutionary roots and is not a modern man-made phenomenon.

Of all of the world’s species, humans and chimpanzees are among the few to engage in co-ordinated attacks on rival members.

The study began as a response to a growing number of primate experts and anthropologists claiming that chimp-on-chimp violence was a result of human impact on the animals, such as habitat destruction, rather than natural adaptive strategies for finding food sources or securing mates.

The research from an international coalition of ape researchers, published today in the journal Nature, suggests that human encroachment and interference is in fact not a cause of chimp-on-chimp aggression. Waging war and killing their own kind is simply a natural way for their communities to survive and develop.

The team of 30 experts assembled data from 18 chimpanzee communities gathered over five decades that included analysis of 152 killings by chimpanzees.

Variation in killing rates was unrelated to measures of human impacts but increased in larger populations and groups with a high number of males. Most were carried out by males on other males from neighbouring groups – supporting the assumption this behaviour is related to natural adaptive strategies.

Michael Wilson, of Minnesota University who has studied chimps deep in the Congo forests for 14 years, said: “This is an important question to get right. If we are using chimpanzees as a model for understanding human violence we need to know what really causes chimpanzees to be violent.”

Dr Morgan said that wild chimpanzee communities were often divided into two broad categories by scientists, depending on whether they exist in pristine wild environments or “human disturbed” environments.

He said the sites they studied spanned all types of chimp community and “we found human impact did not predict the rate of killing among communities.”

He added: “The more we learn about chimpanzee aggression and factors that trigger lethal attacks among chimpanzees the more prepared park managers and government officials will be in addressing and mitigating risks particularly with changing land use by humans in chimpanzee habitat.”

Professor Joan Silk, of Arizona State University, reviewed the results for the journal Nature and said they should put the debate on what makes chimps wage war to rest – but will “probably not be enough to convince everyone”. - Daily Mail