by Frans de Waal
[Film by The Department of Expansion.]
For many years, anthropologists and biologists have been comparing the aggression of animals with human warfare. It started with Konrad Lorenz in the 1960s, and remains a popular endeavor. We have an aggressive instinct that leads to warfare, hence war will always be with us. This message was a bit hard to accept from Lorenz, an Austrian who served in the German army during WWII, but the debate continues as seen in the video above featuring interviews with Steven Pinker, Richard Wrangham, and myself.
Part of the problem is that modern warfare seems to have little to do with the raw aggressive instinct. Modern warfare rests on a tight hierarchical structure of many parties, not all of which are driven by aggression. In fact, most are just following orders. The decision to go to war is typically made by older men in the capital. When I look at a marching army, I don’t see aggression in action. I see the herd instinct: thousands of men in lock-step, willing to obey superiors.
In recent history, we have seen so much war-related death that we imagine that it must always have been like this, that warfare is written into our DNA. In the words of Winston Churchill: “The story of the human race is War. Except for brief and precarious interludes, there has never been peace in the world; and before history began, murderous strife was universal and unending.” But is Churchill’s warmongering state-of-nature any more plausible than Rousseau’s noble savage? Although archeological signs of individual murder go back hundreds of thousands of years, we lack similar evidence for warfare (such as graveyards with weapons embedded in a large number of skeletons) from before the agricultural revolution. Even the walls of Jericho — considered one of the first pieces of evidence of warfare and famous for having come tumbling down in the Old Testament — may have served mainly as protection against mudflows.
Long before this, our ancestors lived on a thinly populated planet, with altogether only a couple of million people. Before this, about 70,000 years ago, our lineage was at the edge of extinction living in scattered small bands. A study of mitochondrial DNA by genographer Doron Behar suggests: “Tiny bands of early humans developed in isolation from each other for as much as half of our entire history as a species.” These are hardly the sort of conditions to promote continuous warfare. My guess is that for our ancestors war was always a possibility, but that they followed the pattern of present-day hunter-gatherers, who do exactly the opposite of what Churchill surmised: they alternate long stretches of peace and harmony with brief interludes of violent confrontation.
Comparisons with apes hardly resolve this issue. Since it has been found that chimpanzees sometimes raid their neighbors and take their enemies’ lives, these apes have edged closer to the warrior image that we have of ourselves. Like us, chimps wage violent battles over territory. Genetically speaking, however, our species is exactly equally close to another ape, the bonobo, which does nothing of the kind. Bonobos can be unfriendly to their neighbors, but soon after a confrontation has begun, females often rush to the other side to have sex with both males and other females. Since it is hard to have sex and wage war at the same time, the scene rapidly turns into a peaceful gathering. Lethal aggression among bonobos has been unheard of.


