Deadly wars may be the result of modern technology blended with our Stone Age instincts. Humankind has just 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. The killings continue today in Sierra Leone, East Timor and Sudan, to name a few.

 

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 to themselves. 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?

 

War deaths have risen dramatically in the 20th century.

 

*There is no information available for number of deaths per 1,000 people in the 1st-15th centuries. **20th century data is up to 1995. (Source: William Eckhardt, "War-Related Deaths Since 3000 BC," Bulletin of Peace Proposals, December 1991 and Ruth Leger Sivard, World Military and Social Expenditures 1996)

 

Young Men More Likely to Wage War

 

According to Weiner, a critical factor in the escalation from conflict to violence, is the percentage of young, unmarried males in a population. He and co-author Christian Mesquida studied the demographics of 153 nations since the 1960s, comparing those that have remained peaceful and those that have been at war. Turns out, there is a difference

 

"Whenever young people represent a relatively small portion of the population times are relatively tranquil, they wrote in their study. "But when a large portion of a country,s population is young there is likely to be turmoil and political violence.

 

Examples include the Congo, Rwanda, Sudan, even the former Yugoslavia.

 

Aggressive wars seem to happen when the percentage of young men " ages 15 to 29 " reaches 35 to 55 percent of the adult male population. "I think that young males are hard-wired to form groups and under the right circumstances, to act aggressively in groups, Wiener says.

 

If Wiener is right, some areas ripe for conflict are China and India - the world,s two most populous nations - as well as Pakistan, parts of the Middle East and Africa.

 

So with evolution and demographics against us, what can be done to lessen the chances of war?

 

Natural selection over millions of years has brought us to this violent point and it won,t be swinging the other way any time soon.

 

Besides, says Weiner, "what drives this stuff ultimately is demographics.

 

That may be, but there are certain actions that can be taken to derail our baser human tendencies.

 

Peace has a better chance in a more interconnected world, where all nations keep tabs on one another. International watchdogs big and small " the United Nations, NATO, Amnesty International and others " are already helping to keep imbalances of power in check.

 

Population control can reduce conflicts by making sure that every nation has adequate resources.

 

Such efforts may not bear fruit for generations, but they do provide seeds of hope for a more peaceful 21st century.

 

War and Young Men

 

A demographic study shows a strong correlation between the percentage of a nation's male population that is between the ages of 15 and 29 and incidences of collective aggression - war, ethnic violence, etc.

 

 

NATION     % AGES 15-29   		  RECENT 
			   15-29 			COLLECTIVE AGGRESSION?

Cambodia		55						Yes
Somolia		55						Yes
Uganda			55						Yes
Iraq			54						Yes
Rwanda			54						Yes
West Bank		54						Yes
Congo			53						Yes
Gaza			53						Yes
Algeria		50						Yes
Colombia		49						Yes
Angola			48						Yes
Ethiopia		48						Yes
Pakistan		48						Yes
Eritrea		46						Yes
Indonesia		46						Yes
Chechnya		44						Yes
China			43						Low level
India			43						Low level
USA				32						No
Canada			31						No
Russia			31						No
Sweden			26						No

 

Source: Christian Mesquida & Neil Wiener. Data: 1990, showing percentage of young men in the adult male population.