I read this short article and was at first disposed to think the author right. He's critiquing a paper on the "male warrior hypothesis" which uses evolutionary psychology to explain why modern men and women treat "outgroup members" as enemies. Outgroup members are, as you'd expect, people unlike themselves. The authors of the paper hope that "understanding why male outgroup members elicit particularly negative emotions, cognitions and behaviours is the first step towards a sensible policy to improving intergroup relations in modern societies." They say anthropological studies show men in pre-historic communities to have been directed by (paraphrasing) a conflict-based evolutionary strategy to perpetuate their kind. The goal of these men was "to gain access to mates, territory and increased status" by displaying "acts of intergroup aggression." These acts — raids, warfare, and the like — threatened the communities' women who, as you'd expect, therefore feared outgroup men. The paper describes this as "selection pressure for psychological mechanisms that bias women against outgroup men." The main trouble with the warrior hypothesis is that it's untestable. The entire argument is based on supposition. There's no way to know whether communal male aggression was an evolutionary adaptive behavior or rather a component of cultural practices which developed as communities competed for scarce resources.
In Psych Today, Prinz says the male warrior hypothesis is one way to look at the problem of male violence, but not the best one. He says history is a better guide. Prinz isn't an actual historian however. He's a philosopher who specializes in psychology and his argument isn't any better supported by available evidence than the one he attacks. History, he says, shows that men fight each other simply because their strength gives them power and, having attained power, they must fight to retain it. He reminds us that both men and women try to obtain desirable resources and that men are naturally stronger than women. Before mankind invented agriculture, men didn't fully dominate women because they depended on women to gather plant food while they, the men, specialized in bringing home game. After the invention of farming, he says, women stopped being providers and became economically dependent on men. Having gained this economic ascendancy, men exploited it; and now — in modern times — they (paraphrasing) mistreat women, philander, and control both labor markets and political institutions. He says, "Once men have absolute power, they are reluctant to give it up. It took two world wars and a post-industrial economy for women to obtain basic opportunities and rights." These broad generalizations are given as self-evident.
Whether verifiable or not, they do not contradict the warrior hypothesis since they deal with man-woman relations, not man-man. Regarding the latter, Prinz says that having achieved dominance over women, men are forced to fight to defend it — not against women, but against other men "who find themselves without economic resources [and] feel entitled to acquire things by force if they see no other way." This is a re-statement of the warrior hypothesis in terms of cultural rather than biological adaptation. The restating isn't very intellectually satisfying. Although Prinz does a good job of criticizing the RoySoc paper, the alternative he puts forward isn't supported by better evidence. "Patterns of violence," he says, "can be dramatically altered by historical forces. Attitudes towards slavery, torture, and honor killing change over time, and this should make us realize that the biological contributions to violence may be greatly outweighed by the sociological." He says that ascribing male violence to cultural/sociological/historical causes is simpler than ascribing it to biological/evolutionary ones and that accepting his historical hypothesis leads to a superior set of predictions. To his credit, Prinz says the subject is a complex one, but his approach seems no less simplistic that the one he criticizes.
Prinz's article caught my eye because I've recently finished reading Mitchell Zuckoff's Lost in Shangri-La. It's a good read. As is often the case, reviewers on amazon.com tell its strengths and weaknesses and give useful precis along the way. This for example, says pretty concisely what it's about: Narrative History at its Best by "Man of La Book" May 3, 2011.
It's a story that can be framed quite a few different ways. The book's blurb focuses on the high drama of harrowing adventure:
On May 13, 1945, twenty-four officers and enlisted men and women stationed on what was then Dutch New Guinea boarded a transport plane named the Gremlin Special for a sightseeing trip over "Shangri-La," a beautiful and mysterious valley surrounded by steep, jagged mountain peaks deep within the island's uncharted jungle.Newspapers at the time framed the story around the woman: a WAC corporal, Margaret Hastings, who was petite, feminine, plucky, and attractive. Nothing in her life had prepared her for the horror of witnessing the death of the plane's other passengers, the hardships she faced in descending from the mountain-side crash site to the valley below, the experience of living among savages once reaching the valley, and the fears associated with an extremely dangerous rescue plan.
But the pleasure tour became an unforgettable battle for survival when the plane crashed. Miraculously, three passengers survived – WAC Corporal Margaret Hastings, Lieutenant John McCollom, and Sergeant Kenneth Decker.
Emotionally devastated, badly injured, and vulnerable to disease, parasites, and poisonous snakes in the wet jungle climate, the trio was caught between man-eating head hunters and the enemy Japanese. With nothing to sustain them but a handful of candy and their own fortitude, they endured a harrowing trek down the mountainside – straight into a primitive tribe of superstitious natives who had never before seen a white man or woman.
Lost in Shangri-La recounts this incredible true-life adventure for the first time. A riveting work of narrative nonfiction that vividly brings to life an odyssey at times terrifying, enlightening, and comic, Lost in Shangri-La is a thrill ride from beginning to end.
Zuckhoff, himself a newsman, gives multiple frames. He provides a lot of background, enough so that the back-stories sometimes foreground themselves. These back-story frames include life behind-the-lines in the Pacific theater as the end-game of the war against Japan began to play itself out, youthful high-jinks among men and women who were close to but not immediately involved in combat, and both minor mis-steps and serious errors committed by men in high command. He shows us raw competition among commanding officers and their sometimes extravagant headline-seeking behavior. He shows the Army's eagerness to put forward a sensational story in a way that showed the stateside public its own competence and can-do ability to accomplish difficult tasks.
Zuckhoff deals as well with the story of plans and their execution: the technical problems of extracting survivors. He also turns his focus on the odd-ball personalities that are revealed when war brings together people who wouldn't otherwise have had much to do with each other. And he shows how a crisis can produce emergence of excellent military values (calm leadership under grueling conditions, stoic cooperation and mutual support shown at extremity of endurance, and the like).
He reveals as well the casual, unthinking prejudice among white Americans of the time. Thus for example the paratroopers who eventually arrive to set up the extraction of the three survivors are "boys" simply because they are Philippine Americans and their part in the dramatic rescue is for this reason ignored by the press. And the villagers of Uwambo with whom the three survivors lived for weeks are simply "natives," "stone-age tribesmen," or, worse, "man-eating head hunters."
The connection between this book and the debate over the male warrior hypothesis lies in Zuckoff's discussion of these locals, the Uwambo villagers and the Dani peoples of the Baliem Valley. The men of this valley were warriors and their culture was largely based on aggression and violence, sneak attacks and pitched battles.
With temperate climate and fertile soil, the valley can support subsistence farming and, over the many centuries of their life in it, its native inhabitants had learned to live well. The mountain walls hemming them in, however, limited the number of people that this climate and soil could sustain and — whether as an evolutionary adaptation or a cultural accretion (or a combination of the two) — the locals came to possess means to limit population growth. Their main tactics were two: married couples observed sexual abstinence for five years following the birth of a child and the men of the tribe practiced what I find is called Endemic warfare, that is they made ritualistic war against each other in pitched battles and small raids.
The five-year ban on sex was accompanied by separation of sexes. Men and women formed marriage partnerships, but they did not live in the same buildings. Instead men and women each slept in their own quarters; couples met together privately (and infrequently) for sexual intimacies. These practices contradict the evo-psych warrior thesis since it is based on the assumption that a very simplistic version of "reproductive success" is the driving force of pre-historical communities. Further, the reasons giving for fighting were not the acquisition of more sexual partners, but the appeasing of ancestral ghosts, and, in practice, warriors did not take women captive but in raids against opposing villages were more likely to kill them. In non-lethal raiding, warriors would not steal women but rather pigs.
The villagers were "stone age" in the sense that they had no metal. Their tools and weapons were made of wood and stone, but they were not hunter-gatherers. They grew root crops, mostly sweet potatoes, and raised pigs. Contra Prinz, their farming practices did not lead to male domination of women, however. Men and women cooperated in farming tasks with the men preparing fields for planting and the women doing most other farming tasks. The dominant warriors were also the most influential men in the village, but their power was greatly limited, mostly based on persuasion, and women contributed to decision-making to some extent.
Men kept their spears, bows, and arrows close at hand at all times and each village built itself a watch tower which they kept manned at all times. Villages made alliances with their neighbors and it was the resulting confederations that engaged in frequent ritual battles with one another. The warriors participating in these battles aimed at wounding or killing an enemy in order to appease the ghost of an ancestor. Much of the time a single wounding or killing would bring a battle to an end. And when an enemy was killed the warriors who had killed him would dismember the body and, sometimes, ritualistically cook and consume parts of it. Anthropologists report that actual warfare — secular battles intended to kill many enemies and destroy their villages — were rare, occurring perhaps only every ten or twenty years.
These images are stills from the film Dead Birds, a 1964 documentary produced as part of a Harvard-Peabody Expedition to study the highlands of New Guinea. Anthropologist Robert Gardner was director; Peter Matthiessen wrote the voice-over narrative.
From what I've read it seems to me the Dani culture was unusually well balanced and resistant to change. Dani do not appear to have suffered the ills of many other peoples. So far as I'm able to determine, they did not have famine, they were not subject to epidemics, their homeland was not threatened by outside forces more powerful than theirs, their environment did not include predators which threatened their livestock nor plant diseases which threatened their crops. They lived above the malarial tropics and below the unwelcoming frost line. Their climate provided more than enough rainfall and their soil was easy to keep fertile.
They seem to have realized that their self-containment was a strength even to the extent of rejecting tools, weapons, and clothing offered them by the crash survivors and their rescuers. Zuckoff writes that the Dani kept their visitors outside their village. The WAC, Margaret Hastings, who never learned any of the Dani language or even the names of those she met, nonetheless was the only caucasian able to form close acquaintance with them. Knowing very little about their culture, she perceived that they were adamant in preserving the balance they'd achieved from outside interference. He says:
Similarly, an anthropologist reports that missionaries made little headway in attempting to convert the Dani to Christianity: "In the middle of 1962 a mission post by one of the Baliem tributaries had to be evacuated, because of the hostility of the great majority of the Dani in that region. During the last months before evacuation police guarded the station in order to deter attacks."
All the same, the Dani were not rigidly resistant to change. Neither the sweet potatoes that were their staple crop nor the pigs, which functioned both as food source and as repository of personal wealth, were native to the island. Sweet potatoes, for example, were crops originating on the South American continent and they are thought to have been introduced in the seventeenth century. The culture may have been "stone age" in the sense that it lacked metal tools and weapons, but its food sources and presumably also farming practices were relatively modern. This may show an unusual cultural instinct to accept change, but only that which could maintain or strengthen the natural balance which this people had been able to achieve.
The inhospitable mountain peaks which guarded the Dani against incursions from the world outside, did not protect them from airborne intruders after World War II came to a close. Despite their instinct for preservation and resistance to outside influence, the balance which the Dani enjoyed did not long survive first contact with the men and women of western civilization. They still exist as a people, but now principally as objects of tourist interest and clients of the Indonesian state. Still, says an author of the wikipedia on the Dani: "Changes in the Dani way of life over the past half century are tied to the encroachment of modernity and globalization, despite tourist brochures describing trekking in the highlands with people from the 'stone age'. Observers have noted that pro-independence and anti-Indonesian sentiment tends to run higher in highland areas than for other areas of Papua. There are cases of abuses where Dani and other Papuans have been shot and/or imprisoned trying to raise the flag of West Papua, the Morning Star."
Unofficial Morning Star flag, used by supporters of West Papuan independence; source: wikipedia}
"Why Are Men So Violent?" Maybe it's the wrong question to ask.
This is a Google Map of Papua New Guinea. The valley is to the west (left) of the white boundary line. It runs east-west within the mountains that enclose it.
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Why Are Men So Violent? in Psychology Today, by Jesse Prinz, Ph.D. (Feb 3 2012)
The Baliem Valley and Dani Culture West-Papua by Øystein Lund Andersen gives some handsome photographs
If Englishmen called this playing, it would be impossible to say what they would call fighting 11 February 2012
S. Glover & T. Noble, The history of the county of Derby (London, 1829, 2 vols), vol. I, p. 310.
Film: DEAD BIRDS (1963) 83 mins. Robert Gardner, a lecture by Karl Heider (pdf)
Visit to Shangri-La/Baliem Valley by Mitchell Zuckoff (photo gallery)
HERE BE CANNIBALS RECENT CANNIBALISM IN NEW GUINEA
Dani people on wikipedia
Dead Birds on wikipedia
1945 New Guinea Gremlin Special rescue on wikipedia
New Guinea Highlands on wikipedia
Richard Archbold on wikipedia
A History of Research on Warfare in Anthropology by Keith F. Otterbein in American Anthropologist, New Series, Vol. 101, No. 4 (Dec., 1999), pp. 794-805 (Published by Blackwell Publishing on behalf of the American Anthropological Association) Stable URL: http://www.jstor.org/stable/684054
Dani Sexuality: A Low Energy System by Karl G. Heider in Man, New Series, Vol. 11, No. 2 (Jun., 1976), pp. 188-201 (Royal Anthropological Institute of Great Britain and Ireland) Stable URL: http://www.jstor.org/stable/2800204
Culture Contact, Cultural Ecology, and Dani Warfare by Paul Shankman in Man, New Series, Vol. 26, No. 2 (Jun., 1991), pp. 299-321 (Royal Anthropological Institute of Great Britain and Ireland) Stable URL: http://www.jstor.org/stable/2803834
At an altitude of 5200 feet, the Grand (or Balim) Valley is more of a plain than a valley, roughly 28 miles long and 9 miles wide; inside its walls live 50,000 Dani. The valley's most impressive feature is the complex system of gardens that covers its floor. ... A garden may take up to three months to prepare. Men, working in co-operative groups, do the heaviest work while the women do the lighter work. ... The sweet potato is, however, the major source of food for the Dani, and the labyrinthian pattern of the gardens is a result of the special needs of this single plant. Sweet potatoes are sensitive to drought and flooding. The balance between too much and too little moisture is handled by the Dani through labour-intensive drainage systems. ... [In addition] almost every man tries to maintain a pig herd, which is looked after by his wives and children. .. The garden remains made excellent pig fodder. So as the Dani came to rely more on sweet potato cultivation, they were able to cope with an expanding pig population. Sweet potatoes were first domesticated in South America and were probably introduced into New Guinea no more than 450 years ago. ... With the adoption of the sweet potato, population growth rates may have increased and a greater proportion of the forests in the Grand Valley would have been converted to arable land. In this sense, indirect culture contact, responsible for the original introduction of the sweet potato, was a major cause of the changing cultural ecology of the New Guinea Highlands.SOME COMPARATIVE REMARKS ABOUT THE DANI OF THE BALIEM VALLEY AND THE DANI AT BOKONDINI by A. PLOEG in Bijdragen tot de Taal-, Land- en Volkenkunde, Deel 122, 2de Afl. (1966), pp. 255-273 (KITLV, Royal Netherlands Institute of Southeast Asian and Caribbean Studies) Stable URL: http://www.jstor.org/stable/27860611
When viewed from an ecological perspective, it is apparent that the Grand Valley Dani occupy a rather narrow environmental zone outside of which they cannot support themselves at current population levels. Below about 4000 feet is the malarial zone, while above about 7000 feet misting from clouds limits this kind of Highlands horticulture.
[Dani warfare involves] hundreds of men on each side of a designated public battleground firing arrows in a highly individualistic fashion. The rationale for ritual warfare is revenge in order to placate the ghosts of the dead. These frequent wars are generally inconclusive and casualties are low. Raids involving clandestine attack by a dozen or so warriors are also included under the rubric of ritual war (Heider 1979: 99), but are often more deadly than the great ritual battles.
Secular warfare, on the other hand, does not invoke ideological rationales concerning spirits of the dead. It is brief and infrequent, employing a co-ordinated, large-scale clandestine attack at dawn; large numbers of men, women and children are killed; property is destroyed or taken and territorial boundaries are reworked.2 But what is the relationship between these types of war?
Most Dani activities are in some way connected with pigs, gardens and war, and daily life revolves around these central themes. ... Ritual war is primarily a low risk, military strategy designed to prevent secular warfare. ... Should a group fail to make a credible showing of warriors during the ritual phase of warfare, it may seem vulnerable to its nominal allies or enemies and become the target for an all-out secular attack ... The younger men - the warriors - who occupy the watchtowers so critical to the defense of life and territory. Watchtowers overlook the frontiers where raids and skirmishes often take place. The men sitting in these 30-foot towers provide early warning against attack by the enemy.
The Dani have a five year post-partum taboo on sexual intercourse. This long period of sexual abstinence has implications for population growth, for if child-bearing does indeed take place at five to six year intervals, the population growth rate may be very low. Most women do not have more than two children and Heider reports that only one of 170 married women in the Dugum neighbourhood had even four children (1979: 80). Peters concurs with this finding and adds the possibility of high infant mortality rates (1975: 30). If the Dani are reproducing at low levels, and given an almost 30 per cent. mortality rate from all kinds of warfare (Heider 1970: 128), then population growth may be negligible. Unfortunately, at present, no accurate data are available on actual Dani population growth rates in the Grand Valley.
Extract: "In the middle of 1962 a mission post by one of the Baliem tributaries had to be evacuated, because of the hostility of the great majority of the Dani in that region. During the last months before evacuation police guarded the station in order to deter attacks. ... Men and women sleep separately. .. The men, either on their own or in a group, clear the tract and, if necessary, surround it with a fence to keep the pigs out. Subsequently they subdivide the tract into plots and allot each plot to one woman, either a wife or a married or unmarried adolescent daughter or sister. The members of the household to which this woman belongs consume the greater part of the yield of her plot. The rest is distributed to working parties, visitors and so on. ... In all political communities a vague hierarchy of big men exists, headed by the best warrior and war leader. In daily life they are not distinguished by clothing and finery. They work as hard as or even harder than the other men. On most occasions big men are not recognizable from the behaviour other members of the community adopt towards them. It is not quite clear what power and authority the Baliem Valley big men possess. Bromley writes that their voice is important during meetings but that they may be overruled (W.P.i.D.E., 1962, 5), Heider mentions that if a big man wants his suggestions to be accepted by the other men, he has to be very careful in choosing his suggestions and to gauge them to the feelings of the others."
 The paper is "Evolution and the psychology of intergroup conflict: the male warrior hypothesis" by Melissa M. McDonald, Carlos David Navarrete, and Mark Van Vugt, and it appears in Philosophical Transactions of the Royal Society, March 5, 2012, pp 670-679. It's behind the RoySoc paywall but is available here as pdf for free. Abstract: "The social science literature contains numerous examples of human tribalism and parochialism—the tendency to categorize individuals on the basis of their group membership, and treat ingroup members benevolently and outgroup members malevolently. We hypothesize that this tribal inclination is an adaptive response to the threat of coalitional aggression and intergroup conflict perpetrated by ‘warrior males’ in both ancestral and modern human environments. Here, we describe how male coalitional aggression could have affected the social psychologies of men and women differently and present preliminary evidence from experimental social psychological studies testing various predictions from the ‘male warrior’ hypothesis. Finally, we discuss the theoretical implications of our research for studying intergroup relations both in humans and non-humans and discuss some practical implications."
 SOME COMPARATIVE REMARKS ABOUT THE DANI OF THE BALIEM VALLEY AND THE DANI AT BOKONDINI by A. PLOEG in Bijdragen tot de Taal-, Land- en Volkenkunde, Deel 122, 2de Afl. (1966), pp. 255-273 (KITLV, Royal Netherlands Institute of Southeast Asian and Caribbean Studies) Stable URL: http://www.jstor.org/stable/27860611
 Culture Contact, Cultural Ecology, and Dani Warfare by Paul Shankman in Man, New Series, Vol. 26, No. 2 (Jun., 1991), pp. 299-321 (Royal Anthropological Institute of Great Britain and Ireland) Stable URL: http://www.jstor.org/stable/2803834)