Seeds of warfare precede agriculture.

Stone Age hunter-gatherers are often billed as the peaceful precursors of agricultural peoples who cultivated frequent warfare along with their crops beginning around 5,000 years ago. But cave paintings in northern Australia, some dating to 10,000 years ago or more, bluntly blast that assumption.

In fact, these scenes painted by aboriginal peoples represent the earliest known portrayals of organized warfare, according to two researchers who have studied paintings at more than 650 Australian sites.

Depictions of large battles, small skirmishes, and people attacking one another with spears and boomerangs document an ancient tradition of warrior art by aboriginal hunter-gatherers that extends from pre-agricultural times to the early part of this century. Stone Age humans thus possessed a full-fledged capacity for waging war, argue Paul Tacon, an anthropologist at the Australian Museum in Sydney, and Christopher Chippendale, an archaeologist at the University of Cambridge in England.

"Warfare is often seen as a side effect of sedentary farming and then of urban societies," Chippendale contends. "But organized conflict is decidedly a characteristic of mobile hunter-gatherers and Homo sapiens in general."

The researchers describe their findings in the just-released October 1994 CAMBRIDGE ARCHAEOLOGICAL JOURNAL.

The roots of warfare may stretch back millions of years (SN: 2/9/91, p.88), but little archaeological evidence of such activity exists. However, violence does occur in modern hunter-gatherer groups; in fact, overall murder rates in some groups exceed those in Western nations (SN: 2/6/88, p.90).

Tacon and Chippendale's analysis, based on 5 years of fieldwork in which they recorded details from many previously discovered cave paintings as well as from some at new sites, uncovers three phases of aboriginal warfare in the Arnhem Land region of Australia's Northern Territory.

In the earliest phase, dating roughly to between 10,000 and 6,000 years ago, paintings show human figures engaged in small skirmishes and one-on-one combat, throwing boomerangs, dodging spears, and chasing each other with their weapons raised.

A second phase, coinciding with a rise in world sea levels around 6,000 years ago and continuing for several thousand years, reveals more simply drawn figures wielding weapons such as boomerangs, barbed spears, and spear throwers. Several sites contain paintings of large battles between opposing groups of these figures.

Battle scenes occur most frequently in paintings of the third phase, which runs from 3,000 years ago to the present. Boomerangs as weapons had fallen out of use by this time. Combatants strike a variety of poses suggestive of warfare, and wounded or dying figures appear, often with spears sticking through their bodies.

Expansion and elaboration of aboriginal warfare took place because rising seas flooded coastal areas of Arnhem Land about 6,000 years ago and forced inhabitants of those regions to move inland, where others already lived, the researchers argue. Competition for land and food led to the formation of social groups with separate languages and cultures, they propose. Current aboriginal rock art, social organization, and stone tool use derive from those early population divisions, according to Tacon and Chippendale.

"Conflict, aggression, warfare, and militarism ... are not unique to 'developed' civilizations," writes Joan Vastokas, an anthropologist at Trent University in Ontario, in a comment accompanying the new report. "Only the technology of warfare varies in scale and style from spears and boomerangs to fighter planes and nuclear warheads."

Several commentators object that the Australian rock art may portray symbolic or ritual events that had nothing to do with actual warfare.

Andree Rosenfeld, an archaeologist at the Australian National University in Canberra, doubts the importance of this concern, "since the depictions must illustrate conceivable practice."