Chimpanzees wired for war, 50-year study in Africa shows
Group violence among African communities is 'inherent, not caused by impact of humans'
Deadly "warfare" between chimpanzees stems from an inherent streak and not, as some have suggested, from human interference, a study said.
Zoologists, led by the famed Jane Goodall, have speculated for years on the causes of "chimpanzee wars" among man's closest genetic relatives.
One theory is that the apes are made more aggressive as a result of human influence: loss of habitat or food creates ever-greater competition for resources.
But new research, published on Wednesday in the journal Nature, said coordinated violence is an evolutionary strategy.
Chimps kill to wipe out rivals, thus gaining territory, mates, water or food, it suggests. In Darwinian terms, they seek an advantage to help them survive and hand on their genes to future generations.
The evidence comes from an examination of five decades of research into 18 closely studied chimpanzee communities in African forests. The researchers pored over 152 killings by chimps, most of which were carried out by males acting together.