Om biologiskt arv

PEOPLE are not alone in waging war. Their closest living cousins, chimpanzees, also slaughter their own kind—in brutal attacks that primatologists increasingly view as strategic, co-ordinated assaults rather than random acts of violence.

A report just published in Current Biology gives a detailed picture of organised conflict between chimpanzees. Drawing on a decade of observations in the field, it concludes that, as with human conflict, wars between chimpanzees are fuelled by territorial conquest.

Using GPS to map patrol routes and attack locations, they saw that the Ngogo chimps’ reconnaissance fanned mainly beyond their north-eastern border, encroaching onto the land of a neighbouring group. Almost all of the killings occurred in this disputed territory, which sported particularly fine stands of the chimps’ favourite fruit-tree. By the time the study ended, the Ngogo group’s campaign had displaced its rivals completely, annexing the north-eastern lands and enlarging its range by 22%.