A really thorough and well-written article in Scientific American, which as far as I know is not a feminist publication:
War Is Not Part of Human Nature
Do people, or perhaps just males, have an evolved predisposition to kill members of other groups? Not just a capacity…
“Lethal group attacks, according to these arguments, emerged only when hunter-gatherer societies grew in size and complexity and later with the birth of agriculture. Archaeology, supplemented by observations of contemporary hunter-gatherer cultures, allows us to identify the times and, to some degree, the social circumstances that led to the origins and intensification of warfare.
Many social arrangements impede war, such as cross-group ties of kinship and marriage; cooperation in hunting, agriculture or food sharing; flexibility in social arrangements that allow individuals to move to other groups; norms that value peace and stigmatize killing; and recognized means for conflict resolution. These mechanisms do not eliminate serious conflict, but they do channel it in ways that either prevent killing or keep it confined among a limited number of individuals.
People are people. They fight and sometimes kill. Humans have always had a capacity to make war, if conditions and culture so dictate.
But those conditions and the warlike cultures they generate became common only over the past 10,000 years — and, in most places, much more recently than that. The high level of killing often reported in history, ethnography or later archaeology is contradicted in the earliest archaeological findings around the globe.” (emphasis mine)