Dear Dr. Universe,
Why is there war in the world?
Porto Alegre, Brazil
I’ve got good news and bad news. First the bad news. Humans, especially men, are violent by nature. It makes them feel important. And the good news? Humans are a lot less violent than they used to be!
I tracked down John Patton, who is an anthropologist here at Washington State University. He studies the influence of human evolution on politics, violence and warfare.
Needless to say, you can’t very well study a subject like this in a laboratory. So Professor Patton went to live with the Achuar people in the Ecuadorian Amazon. The Achuar are related to the Shuar, who live in the same valley.
Have you ever seen a shrunken head in a museum? They were shrunk by the Shuar. In the recent past, when Shuar boys were ready to become men, in a “rite of passage” they took hallucinogens, traveled to a sacred waterfall and met an animal spirit. After this, they went off to find the head of an enemy to shrink.
Unfortunately for the Achuar, most of these heads belonged to them.
Even without the headshrinking, the Shuar and Achuar are pretty violent. Traditionally, an Achuar male had a 50 percent chance of being killed by another.
As you probably have figured, these are pretty intense people!
They also make very interesting subjects for Professor Patton to study.
From what anthropologists can tell, the homicide rate for men living in tribal societies is generally about 30 percent. This was before they were affected by outside influences. So the Achuar’s homicide rate is higher than most. So much the better for studying WHY they are so violent.
Let’s think about a few basic ideas about evolution and violence. What seems to make all living things tick is the desire to reproduce and pass on their genes. Whether you’re a flower or a salamander or a human, you are driven by your wish to pass along your genetic traits to the next generation. You think you’ve got something special, and you’d like that to continue after you die.
So—our goal is to pass along our genes. Simple enough. But if that’s the case, why would a soldier go to war and be willing to die for his country? It’s pretty hard to pass along your genes if you’re dead.
And there you have it—one of the main contradictions of human evolution and behavior. How does this make sense?
Professor Patton believes that young men will risk getting killed in order to gain status, to be important in the society and to have more kids to give his genes to! He bases this idea both on his research and on earlier studies.
For example, his adviser, Napoleon Chagnon, found that among the Yanomamo of Venezuela, certain men who are very accomplished killers have on average two and a half times more wives and more than three times as many children as do their more pacifist brothers.
In other societies, we can also see that high status leads to more wives (and mistresses) and more children. In other words, according to Professor Patton’s hypothesis, being a great warrior (being willing to kill and risk your own life) gains you high status, which in our evolutionary past brought males more wives and kids, which fits right in with evolution!
So according to this thinking, humans kill each other for status. You’ve got to realize I’ve really simplified things here. Regardless, that’s not a very cheery thought, is it?
But think about this. As violent as we think our society is, tribal societies (which we came from a long time ago) have homicide rates about 50 times higher than ours. This comparison doesn’t distinguish between homicide and warfare. After all, says Professor Patton, war is just killing okayed by your country. So this rate includes all our wars and atomic bombings and so on. Even including these things, still it seems like maybe we’ve made some progress.
Even though humans can still be pretty awful toward each other, MAYBE—with the help of government and culture—they are getting a little better at keeping from killing each other. I think that’s pretty good news!
Now keep in mind that not every scientist agrees with Professor Patton. There are other ideas for why people are the way they are. But these arguments, backed up by serious research, are what science is all about.