Science / Medicine : Whys of War : Anthropology: Human beings have fought one another for thousands of years, but there are many theories as to the causes.

In a 1971 Motown hit single, Edwin Starr posed the musical question, “War--what is it good for?” His gruff response: “Absolutely nothin’.”

Despite the grimly predictable tragedies of armed conflict, almost all ancient and modern societies studied by anthropologists have engaged in at least periodic bouts of warfare. The ubiquity of organized fighting between human groups--currently brought home by the war in the Middle East--has fired up the scientific study of warfare over the last 30 years and has sparked some bruising academic skirmishes.

A handful of warfare researchers are examining the cultural and anthropological causes of war. These investigators do not praise fighting, but they assume that anything so common in human experience serves some purpose. They search for the “absolutely somethin’ ” that lights the fuse of violence in bands of foragers, tribes of hunter-gatherers, rudimentary political states and modern nations alike.

In the 1960s, as U.S. involvement in Vietnam deepened, anthropological theories of war’s causes and consequences flourished, numbering at least 16 by 1973, says Keith F. Otterbein of the State University of New York at Buffalo. However, he says, only about half of those theories still receive strong scientific support, and no persuasive new theories have emerged.

Although some anthropologists and sociobiologists contend that a genetic tendency toward physical violence greases the human war machine, theories of innate aggression attract few advocates today, Otterbein says. Nevertheless, disputes over the alleged biological roots of combat continue to erupt, ignited in many cases by the work of Napoleon A. Chagnon of UC Santa Barbara, whose studies of warfare have become the most widely publicized research in this field.

Since 1964, Chagnon has conducted fieldwork among the 15,000 Yanomamo Indians who inhabit about 200 villages in the Amazonian jungle of Brazil and Venezuela. He has long stressed the ferocity and frequency of combat between Yanomamo villages.

Chagnon’s latest report concludes that revenge fuels the protracted, bloody battles between groups of men from different Yanomamo villages. Competition for food, water, territory or women creates the initial friction, he says. Minor bow-and-arrow confrontations ensue, escalating rapidly when a death results and the victim’s male relatives exact revenge through raids on the offending village.

Blood vengeance apparently raises the social status and reproductive success of Yanomamo warriors, who represent nearly half of the men in the tribe, Chagnon says. On the average, killers have more than twice as many wives and three times as many children as their peaceable counterparts.

Chagnon contends that reproductive success and fighting prowess probably go hand-in-hand in many human groups, and that this may help explain the great prestige attached to military conquest in both modern and ancient states.

Even if Chagnon’s Yanomamo data holds up, says anthropologist John H. Moore, successful warriors in similar tribal societies sometimes contribute few genes to subsequent generations. Moore, of the University of Oklahoma, cites the 19th-Century Cheyenne Indians of the North American plains as a case in point. The Cheyenne, with a population of about 3,000 divided into bands of 150 to 400 individuals, engaged in fierce warfare with other Indian tribes as well as with U.S. military forces, achieving historical fame with their defeat of Gen. George A. Custer at the Battle of Little Big Horn. In addition to seven warrior bands led by numerous war chiefs, Cheyenne society included 44 peace chiefs, sometimes more than one to a band, who led polygynous extended families.

U.S. Census data collected in 1880 and 1892 revealed that men in the Cheyenne peace bands had a striking reproductive advantage over warriors, Moore reported in the June, 1990, issue of Current Anthropology. The war chiefs stressed celibacy and ritual suicide, while the peace chiefs had numerous wives and children, he says.

Another critic of Chagnon’s research, Marvin Harris of the University of Florida in Gainesville, suggested that war occurs among hunter-gatherers and other “band-and-village” peoples when population growth creates increasingly intense competition for food, especially protein-rich game. He maintains that warfare, for all its brutality, effectively prunes these populations, preventing malnutrition and hunger among survivors--whether the combatants belong to Yanomamo villages or horticultural groups in Papua New Guinea.

The origins of war probably stretch back to Stone Age times, says Robert L. Carneiro of the American Museum of Natural History in New York City. Stone Age battles--fought to avenge murders, wife-stealing or other trespasses often observed among modern hunter-gatherers--served to push small bands of humans apart and keep them separate.

But around 10,000 years ago, the nature of warfare changed, he says. The spread of agriculture increased permanent settlements and human populations. Adjacent villages began to fight over access to farmland. Instead of pushing the communities apart in traditional Stone Age fashion, these wars forged the emergence of the chiefdom, a forced coalition of several formerly independent villages under the control of a paramount chief. With chiefdoms came district chiefs, village chiefs, advisers and other early representatives of social and political complexity.

Archeological signs of war, such as the number of weapons found in graves and heavily fortified occupation sites, increase with the growth of chiefdoms, Carneiro says. Prime examples include Mesopotamia, the Nile Valley and the Peruvian coast.

“War was the one instrument capable of surmounting autonomous villages and deserves careful study as a cause of social evolution,” Carneiro says.

Perhaps the most wide-ranging warfare study to date was conducted during the 1980s by Carol R. Ember and Melvin Ember of Human Relations Area Files, a privately funded research organization in New Haven, Conn. The team analyzed anthropological descriptions of 186 nonindustrial societies, virtually all of which operated on a much smaller scale than modern nation-states. Descriptions ranged from 18th-Century writings on American Indian tribes to recent accounts of African hunter-gatherers.

The Embers say that their unpublished findings offer a tentative theory of war, at least among “simple” societies: The societies that engage in the most warfare express considerably more fear of food shortages caused by expected but unpredictable natural disasters, such as drought, flood or infestation. The fear of others--indicated by child-rearing practices stressing distrust of neighbors--further fuels the tendency to flight, the researchers say.

Parents in warlike societies tend to encourage toughness and aggression among boys, but warfare apparently causes this practice rather than vice versa, the Embers say. When these societies lose wars and come under the control of outside forces, harsh child-rearing methods diminish sharply, they say.

Several researchers say that contact with Westerners has whipped up local conflicts in Africa and elsewhere since the early days of European colonialism.

More than a century ago, for example, Tuareg tribes of northern Africa limited their attacks to small-scale raids on caravans passing through their territory, says Candelario Saenz of the State University of New York at Purchase. The Tuareg extorted camels and other goods from the caravans to support their pastoral way of life, Saenz says. But when France took control of Algeria in the late 1800s, it imposed numerous restrictions on trade in the region. Tuareg groups soon entered into a period of nearly constant warfare among themselves as they competed for the rapidly decreasing supply of goods passing along traditional trade routes.

Another instance of Western contact helping to foment violence occurred more recently in the ethnically mixed African nation of Mauritania, says Michael M. Horowitz of the State University of New York at Binghamton, who has conducted fieldwork there for the past four years.

The completion of a large dam on the Senegal River several years ago expanded farmable flood plains and drew the promise of considerable outside investment by Western agricultural companies, Horowitz says. But the local population, long dependent on farming this fertile river valley, already occupied much of the area.

“The Mauritanian government is now killing and torturing these people to get the land,” Horowitz says. “In the process, they’ve created 100,000 refugees and intensified violence between ethnic groups.”

Whether stimulated by Western contact or not, most of the 120 wars documented since the end of World War II similarly pit large states against smaller nations or ethnic groups the states claim to represent, says Jason Clay of Cultural Survival, a public-interest organization in Cambridge, Mass.

In the aftermath of the international conflict sparked by such aggressions, he says, dictatorships and one-party states ironically solidified their power in many parts of the world, including Africa, the Soviet Union and Eastern Europe.

Moreover, those leaders socked away whatever taxes, internal resources, foreign aid and international loans they could extract for themselves, leaving the rest of the populace destitute, he says.

“The destruction of social and political life at the local level and the stripping away of resources by modern one-party states has led to longer, more widespread wars,” Clay says. “We’ll have more violence at the regional level and the settling of old scores as states fall apart in the post-Cold War world.”

Although Clay’s dire prediction gathers support from the bloody Soviet crackdown on Lithuania’s independence movement and the increasing tensions in other Soviet republics, anthropological research provides room for optimism, says R. Brian Ferguson of Rutgers University in Newark, N.J.

“War is not the human condition,” Ferguson says.

Often, leaders must paint the enemy as inhuman in order to motivate people to kill, he says--and even then, many soldiers come out of combat with severe psychological aftereffects.

“We need to dispense with the idea that people love violence and are doomed to fight,” Ferguson says.