Violence Part of Being Human

Humankind has lived through a hideously violent century. World War I, WWII, wars in Vietnam, Cambodia, China, Bangladesh, Korea, Nigeria and elsewhere have extinguished millions upon millions of lives.

Waging war is nothing new for us humans. Bloody conflicts from the Crusades to Kosovo have been a hallmark of our history. Which raises the questions: Is such behavior simply part of human nature? Are we hard-wired for war?
There´s certainly no definitive answer. But enough scientists have looked into our past - and present - to shed a bit of light on why we do what we do.

New Environment, Old Brain

When interpreting human behavior, it´s best to remember that the strongest human instincts are to survive and reproduce. What we need to satisfy those instincts hasn´t changed much since our primitive ancestors roamed the globe; it´s about getting enough food, water and mates.
Like it or not, write Leda Cosmides and John Tooby, co-directors of the Center for Evolutionary Psychology at University of California, Santa Barbara, "our modern skulls house a Stone Age mind."
Though modern-day aggressors may not be aware of it, those primitive instincts drive their behaviors too. A strong group benefits from attacking a weaker group if in the process the aggressors gain fertile lands, reliable water, greater market share - any resources that improve their collective livelihood.

There´s no denying that aggression has been a good survival strategy. Which is why we humans are genetically hard-wired to fight.
But what triggers that aggression and what can magnify it to the point of a Rwanda or a Kosovo?
Richard Wrangham of Harvard University sees two conditions necessary for what he calls "coalitional aggression," or violence perpetrated by groups rather than individuals. One condition is hostility between neighbors.

Human aggression got more organized with the introduction of agriculture about 10,000 years ago, says J. William Gibson, author of Warrior Dreams: Violence and Manhood in Post-Vietnam America. With farming came the concept of land ownership - and defense - and the development of more complex and organized societies. Suddenly, there was more to covet, more to protect and more people around to help do both.
The other condition for group violence is an imbalance of power great enough that aggressors believe they can attack with virtually no risk tothemselves. Majorities have persecuted minority groups, whether religious, ethnic or tribal, again and again, believing they´re immune from punishment. The tangled turmoil in the former Yugoslavia is only the most immediate example.

Animals Do it, Too
Humans aren´t the only ones who gang up. Chimpanzees, with whom we share 98.4 percent of our DNA, are another. Wrangham, who wrote Demonic Males: Apes and the Origins of Human Violence, describes five chimps attacking one. Four will hold the victim while the fifth breaks bones and rips out the victim´s throat or testicles.
Examples of taking such advantage of imbalances of power are rare in the animal kingdom because that kind of behavior requires a sophisticated level of coordination and cooperation. However, both chimps and humans are certainly capable of it.
"There´s always conflict in societies," says Neil Wiener, an associate professor of psychology at York University. "The issue is, when do these conflicts erupt into violence?"

ABCNEWS.com