Why is the Human Primitive Warrior Virtually Always the Male of the Species?

by J.M.G. van der DENNEN, Center for Peace and Conflict Studies, University Groningen, the Netherlands.

Cultural and/or historical analyses of male and female gender role-bound phenomena, such as the male roles of warrior and soldier, may provide some insight into the complex interactions between culture, society, the military, and the respective sex differences in gender roles. Such analyses, however, are likely to be restricted to what in the language of evolutionary biology is called a proximate explanation. The high degree of pan-cultural similarity (i.e. the universality) of these sexually differentiated roles, role stereotypes and role demands, suggests the possibility of an ultimate evolutionary rationale behind them. It is highly relevant in this context that in chimpanzee 'wars' (Goodall, 1986; Goodall et al., 1979), it is exclusively the males who do the raiding.
In this paper, I shall briefly discuss three theories which attempt to explain why in 'primitive' societies the role of the warrior is virtually confined to the male of the species.


In primitive societies, wars, raids and feuds are primarily or exclusively male 'occupations' and obligations, although exceptions to this general rule have been documented (e.g. 'Warrior Queens': Fraser, 1989). The famous or notorious Amazons of South America and classical Greece are probably not entirely mythical. The female of the species seems to have engaged in fighting or warlike exploits in Angola, Canary Islands, Valley of the Amazon, Patagonia, Central America, California, Hawaii, Australia, Tasmania, Arabia, Albania, and among the Ainu and Apache (Q.Wright, 1942; see also: Davie, 1929; Turney-High, 1949). In most of these cases, however, the role of the women is confined to company, sutler and entertainer, supporter and 'cheerleader', prostitute and nurse, for the benefit of the hard core of male warriors. The Dahomean women-soldier garrisons, on the other hand, have been reported to fight more bravely and more cruelly than their male counterparts (e.g. Sanday, 1981).
The fact that the warrior role is, in primitive societies, virtually confined to the male, is so obvious, or 'natural', that very few scholars have considered it worthy of contemplation or scientific enquiry. Those few theorists who have tried to formulate a (tentative) answer, will be briefly discussed in this paper.
I will not give too much attention to the voluminous body of literature which has pretended to find the answer in the propositions that

(a) Males are (biologically) expendable; and
(b) Males are preadapted as hunters to be warriors.
(c) Males are 'aggressive' by nature, and therefore (predisposed to) wage war.

These, and similar, propositions are not so much false or trivial - in fact, they are not -, but they're just begging the question. Male expendability and predatory preadaptations may have been necessary conditions, they can in no way be regarded as sufficient explanation. Similarly, I do not endorse the simplistic equation of aggression and belligerence. Nor will I seriously consider the proposition that there is some perverse (or degenerated, or malicious) streak in human maleness, as has been argued by some feminist writers.
The relative male expendability argument is so common (most recently e.g. Mukhopadhyai & Higgins, 1988) that it deserves some consideration. What is the argument and what is wrong with it? "Because fewer of them are needed to produce and maintain offspring, from a population maintenance perspective, males are more expendable than females" (Mukhopadhyai & Higgins, 1988). As Rodseth et al. (1991) have explained: First, the argument is vulnerable to all the criticisms of group selection first articulated by Williams (1966). But even if a 'relative expendability' argument were evolutionarily sound, it could not account for the fact that males seem equally expendable in savanna baboons and many other primate groups, yet females in these groups regularly engage in violent competition with other females. Only an investigation of hominoid evolutionary ecology and the resulting patterns of human psychology is likely to answer the question of why males seem to monopolize violence in human societies and not in those of most other primates (Rodseth et al., 1991).
So the question remains: Why are males warriors? Why is collective violence (group aggression, coalitional aggression), in the forms of warring, raiding and feuding, the virtually exclusive domain of the human (and chimpanzee) male? Why is there, in so many cultures, an association between manhood, warriorhood, virility, and sexual prowess and privileges? (The corollary question why the women in so many cultures prefer the ferocious macho warrior as sexual and/or marital partner, will not be considered at the moment).

Let us consider some common sociobiological propositions about the optimal reproductive strategies of males and females, which are supposed to have universal validity (at least for sexually dimorphic species in which the female is the principal parental caretaker):
(1) The ultimate limiting resource for males is females, while the opposite is not the case; (2) The principle of female choice, and male sexual possessiveness and acquisitiveness, among other factors, guarantee that only a proportion of males mate; (3) Consequently, there is fierce competition among males for the sexual favors and reproductive potential of females, the only resource that can convert his fitness into 'evolutionary currency'.
These propositions go far in explaining intermale competitive and agonistic behavior, they do not, however, explain why collective violence is predominantly a male affair.
Now let us consider another set of rather commonly accepted propositions, as recently formulated by Chagnon (1988): (1) Organisms are expected to maximize their inclusive fitness; (2) Conflicts of interest are inevitable; (3) There is competition over material resources and reproductive resources (i.e. mates); (4) Individuals or groups will attempt to appropriate material and reproductive resources from neighbors whenever the probable costs are less than the benefits.
The almost casually added 'or groups' in this last proposition is not particularly helpful, because, as will be seen later on, cooperative, coalitional aggression is conspicuously absent in the animal world. Only very few species have mastered the art.

In the human species, "males cooperate to compete, both socially and physically, against other males in all human societies. In Wrangham's (1982) terms, men universally engage in 'interference mutualism', such that two or more individuals benefit by cooperating against another individual or group. This is to be distinguished from 'noninterference mutualism', in which cooperation reaps a benefit but not at the expense of any other individual. In many nonhuman primates, especially Old World monkeys, females are prone to engage in violent interference mutualism against other females (Wrangham, 1980; Cheney, 1987). Human females, in contrast, are striking in the extent to which they refrain from such violence. Nowhere on earth, as far as we know, do women form war parties to attack other women. This is not to say that women are incapable of being warriors... While individual women use violence against both men and women, they apparently do not form coalitions for purposes of violence against their own sex in the way that men do everywhere" (Rodseth et al., 1991).

Male philopatry and collective cooperation in conflict

Rodseth et al. (1991), Manson & Wrangham (1991), Van Hooff & van Schaik (1992), among others, have noted the association between male philopatry (or female dispersal) in both humans and chimpanzees on the one hand, and the ability to cooperate more or less collectively in order to compete (violently) on the other hand. Small wonder that these authors have proposed evolutionary explanations on the basis of this phenomenon. In the words of Rodseth et al. (1991):
"In the human social pattern, then, with a few possible ethnographic exceptions, males remain with consanguineal kin (in the sense that they maintain important social relationships with them, whether or not they live with them), while females usually do as well but are sometimes isolated from those kin by extreme patrilocality, patriarchy, or warfare. The majority of primates, by contrast, follow a pattern of male dispersal and female philopatry: males migrate from their natal group at sexual maturity, leaving a set of female kin as the core of the society (e.g. Wrangham, 1980, 1987; Pusey & Packer, 1987). Unrelated males may in turn join the group to breed but remain generally antagonistic toward one another, usually forming temporary coalitions if any. By and large, then, the only enduring kinship links are among females, and only females participate in enduring affiliative relationships...
Only in those few species with female-biased dispersal - chimpanzees, hamadryas baboons, red colobus, and perhaps spider monkeys - are there known or suspected to be enduring affiliative relationships among males. Cooperative relationships among females, accordingly, are attenuated or absent in these groups...
In nonhuman primates, then, neither social relationships with genetic kin nor cooperative alliances with nonkin are generally maintained among members of the dispersing sex: philopatry, consanguinity, and cooperation tend to coincide. In humans, however, dispersal patterns predict patterns of kinship and cooperation only weakly, if at all. In this connection, four trends across all human societies are particularly striking: (1) Males maintain consanguineal kin ties, even with matrilocal residence. (2) Females usually maintain consanguineal kin ties, even with patrilocal residence. (3) Males cooperate in conflicts, both social and physical, against other males. (4) Females also cooperate but rarely do so in physical conflicts of females against females."

Sexual stratification

Social control of sex is a cultural universal (Murdock, 1949; Money & Ehrhardt, 1972). It is accomplished by means of a gamut of subtle to crude and cruel ways: slander, rumor, malicious gossip, humiliation, derogation, moral invectives, scandal, ostracism, incarceration, mutilation, and death.
But, because most societies also have a 'double standard' in matters sexual, women generally suffer more from these sanctions than men do.
Collins (1971) has proposed a conflict theory of sexual stratification, which is based on 2 propositions: (1) Human beings have strong sexual and aggressive drives; and (2) Males are physically dominant over females. Men will generally be the sexual aggressors, women will be the sexual prizes for men. The basic feature of sexual stratification is the institution of sexual property: male ownership of females. And the ultimate basis of sexual property rights is male violence. In most societies, women are exchange property, as already suggested by Lévi-Strauss (1949). The ideal of female chastity (including premarital virginity) is an aspect of male property rights and regarded as enforceable only by males. Women are regarded as amoral, unclean and lacking in honor, and hence to be controlled by force.
To these considerations may be added the 'sexual constellation' theory proposed by Nissen (1961, 1971). In brief, his theory states that the forced sexual abstinence of the young male cohorts, (due to the older males' sexual possessiveness and female choice in selecting older and more powerful males as partners) leads to a bitter and inveterate resentment toward women. This ambivalence of attraction and resentment will color the male's entire life. As older and sexually weaker, for example, he will seek to control sex by striving for social and political power. The sexually frustrated young males are controlled by the men's club and the cult of masculinity: an institution most suited for conducting wars.

Freedman (1967), among many others, has pointed out the fierce possessiveness males have for their women and the simultaneous importance of not being outdone or cuckolded by another male. Thus, being made cuckold is perhaps the most frequent cause for within-group murder over the entire world. In many cultures, one can also witness the importance of male bragging sessions about the number of women one has had, and in some societies the relationship between status and number of women possessed is openly acknowledged.
Furthermore, if we bear in mind that in many primitive societies a man is not considered marriageable before he has 'bloodied his spear', or taken a head or scalp; and that in many societies the successful warrior enjoys considerable sexual privileges (Mazrui, 1975); and, lastly, that in many cultures the display of masculinity pays off as (a) direct sexual access to women, and (b) as a deterrence to potential competitors (anti-cuckoldry device); it will be somewhat easier to understand why in so many cultures, manhood is equated with warriorhood (and belligerence and violence in general), as well as with sexual virility and masculinity.

Why is coalitional aggression absent or rare in women?

Tooby & Cosmides (1988) suggest some answers, which may be summarized as follows:
(1) Coalitional aggression evolved because it allowed participants in such coalitions to promote their fitness by gaining access to disputed reproduction enhancing resources that would otherwise be denied to them.
(2) Very few species manifest coalitional aggression because they lack the cognitive sophistication necessary for the multi-individual cooperation involved in such an enterprise.
(3) The optimum level of direct participation in coalitional aggression by human males is extremely sensitive to the probability of success, and the relationship between these variables may help explain why males will engage so readily in warfare when they are confident of success. It can be shown that given (a) certainty of victory, (b) the assurance of a random distribution of risk of death among participants, (c) the assurance of a relatively 'fair' allocation of the benefits of victory, and (d) efficiency in the utilization of reproductive resources on a zero-sum basis, selection will favor participation in the coalitional aggression regardless of the existence or even the level of mortality (within broad limits).
(4) Within a polygynous system with certain formal properties (e.g. access to females being the limiting resource for male reproduction; male labor being comparatively unimportant to female reproduction, etc.), the deaths of some members of a coalition will not decrease the average reproduction of the members of the coalition.
(5) Natural selection weighs decisions on the basis of their average consequences to individuals, summed over evolutionary time; consequently, these factors explain why males can so easily be induced to go to war, despite its lethal effects on many of them. Coalitions of males, when they assess the relevant variables indicating that they are larger or more formidable than any local competing coalitions, should appear to manifest an eagerness and satisfaction in initiating warfare and an obliviousness or insensitivity to the risk they run as individuals, in terms of their individual somatic welfare.
(6) This approach also predicts the striking asymmetry that exists between males and females in coalitional aggression: females are rarely limited by access to males, so that the net reproduction of a coalition of females would drop in direct proportion to the number of females killed. In a curious fashion, males may be so ready to engage in coalitional aggression because it is reproductively 'safer' for them to do so. Females have more to lose, and less to gain, and such differences in consequences should be reflected in psychological sex differences in attitudes towards coalition formation and coalition-based aggression.
As Low (1993; 2000) and van der Dennen (1995) summarized the above arguments: Women have never - during hominid/human evolution - gained from coalitional violence in ways that men have, in terms of direct and indirect reproductive currency.

Nutritional versus reproductive competition

Symons (1979) contrasts 'nutritional competition' with 'reproductive competition', noting that the former is not inevitable, since nutritional adequacy can be specified in absolute terms, but that the latter is inevitable, since reproductive success exists only in comparison. This contrast must be taken into account to understand the evolution of the psychological mechanisms that determine both what constitutes a 'resource' and when a resource is felt to be 'scarce'. Since it is necessary to life, food always is a resource, but it is not always scarce, and hunger can be fully satisfied. Male- male competition for wives, on the other hand, while undoubtedly exacerbated by anything that reduces the number of available women, is the result, not of skewed sex ratios or polygyny, but a male psyche that makes women always a resource and always in short supply. As Lévi-Strauss (1969) writes about the universal polygamous (if not promiscuous) tendency of the human male: "This deep polygamous tendency, which exists among all men, always makes the number of available women seem insufficient... Hence, the demand for women is in actual fact, or to all intents and purposes, always in a state of disequilibrium and tension" (Lévi-Strauss, 1969; p.38).

Women as the proximate cause of fighting and primitive warfare

Fighting for women among exogamous tribes is common (Wright, 1942; Davie, 1929). Sex is closely linked with the entire social organization of primitive people in which blood relationship plays an important role; thus war for maintaining the solidarity of the group is, among the most primitive people, hardly distinguished from war in defense of the family. Breaches of the sex mores - rape or adultery - by nonmembers of the group are perhaps, together with murder of a group member, the most common causes of feuds and wars. A Maori proverb is said to assign women and land as the chief cause of warfare. And Jenness & Ballantyne (1920) report of the D'Entrecasteaux Islanders that "..some question of food or of women lies at the root of most of their hostilities". "The causes for warfare [among the Murngin] are the killing of a member of a clan by man belonging to another clan, and interclan rivalry for women. This latter cause is usually the primary reason for most killings" (Warner, 1930).
Among many people successful warriors and head-hunters acquire prestige without which they are frequently ineligible to marriage. These types of war are often directly encouraged by the women. Pondo women accompanied the army and encouraged the warriors, whom they watched from neighboring hills, by singing salacious songs and tucking their skirts around their waists, thus exposing themselves (Hunter, 1936).

If reproductive success is always directly at stake in male combat, in a sense women are always at least indirectly at stake, and ethnographic evidence indicates that women often are the proximate cause of fighting (e.g. Yanomamö: Chagnon, 1968 et seq.; Queensland tribes: Lumholtz, 1889; Tiwi: Hart & Pilling, 1960; Eskimo: Rasmussen, 1931; Graburn, 1972; Balikci, 1970; Bushmen: Lee, 1969; Eibl-Eibesfeldt, 1974; Arapesh, Mundugumor and Tchambuli: Mead, 1935. As a Maori proverb says: "Women and pigs are the roots of war".
In summary, the evidence supports Berndt & Berndt's (1951:22) view that "the majority of arguments in an aboriginal society are directly or indirectly brought about through trouble over women".

An intriguing feature of Yanomamö social life is the constant fighting over women and sex.
Chagnon (1988) observes that many anthropologists tend to treat warfare as a phenomenon that occurs independently of other forms of violence in the same group. However, duels may lead to deaths which, in turn, may lead to community fissioning and then to retaliatory killings by members of the two now-independent communities. As a result many restrict the search for the causes of war to issues over which whole groups might contest - such as access to rich land, productive hunting regions, and scarce resources - and, hence, view primitive warfare as reducible solely to contests over scarce or dwindling material resources. Such views fail to take into account the developmental sequences of conflicts and the multiplicity of causes, especially sexual jealousy, accusations of sorcery, and revenge killing, in each step of conflict escalation.
Most fights begin over sexual issues: infidelity and suspicion of infidelity, attempts to seduce another man's wife, sexual jealousy, forcible appropriation of women from visiting groups, failure to give a promised girl in marriage, and (rarely) rape.

The rationale of revenge raiding

At first glance, raids motivated by revenge seem counterproductive. Raiders may inflict deaths on their enemies, but by so doing make themselves and kin prime targets for retaliation. But ethnographic evidence suggests that revenge has an underlying rationality: swift retaliation in kind serves as a deterrent over the long run. War motivated by revenge seems to be a tit-for-tat strategy in which the participants' score might best be measured in terms of minimizing losses rather than in terms of maximizing gains.

What is gained and precisely who gains (in the currency of inclusive fitness)?

First, kinship groups that retaliate swiftly and demonstrate their resolve to avenge deaths acquire reputations for ferocity that deter the violent designs of their neighbors. The Yanomamö explain that a group with a reputation for swift retaliation is attacked less frequently and thus suffers a lower rate of mortality. They also note that other forms of predation, such as the abduction of women, are thwarted by adopting an aggressive stance. Aggressive groups coerce nubile females from less aggressive groups whenever the opportunity arises. Many appear to calculate the costs and benefits of forcibly appropriating or coercing females from groups that are perceived to be weak.
If, as Clausewitz suggested, (modern) warfare is the conduct of politics by other means, in the tribal world warfare is ipso facto the extension of kinship obligations by violence because the political system is organized by kinship.
Second, men who demonstrate their willingness to act violently and to exact revenge for the deaths of kin may have higher marital and reproductive success. The higher reproductive success of 'killers' is mainly due to their greater success in finding mates, either by appropriating them forcibly from others, or by customary marriage alliance arrangements in which they seem to be more attractive as mates then 'non-killers'. Among the Yanomamö, 'non-killers' might be willing to concede more reproductive opportunities to 'killers' in exchange for a life with fewer mortal risks and fewer reproductive advantages.

Female-female competition

Although ethnographic reports may sometimes have an androcentric bias that obscures the subtleties of female-female competition, it is certain that intense competition evidenced by organized fighting and killing - as is common among men - occurs nowhere among women.
When women do compete for a man it is not to acquire sexual access, or even a husband, but to protect a substantial and probably irreplaceable investment in a man (Symons, 1979).

What is selected for in a milieu of violence?

Available data on preliterate peoples strongly suggest that during the course of human evolution males regularly fought over females and other fitness- promoting resources. In such a milieu selection is extremely unlikely to favor simple male belligerence, aggressive drives, or territorial imperatives. Human violence usually is a complex group activity.
Good judgment, not simple belligerence, seems to be adaptive in a state of chronic violence.
If the evidence of living peoples can illuminate human evolution, it suggests that during the Pleistocene sexual access to women was in part dependent on achieving positions of leadership. Selection probably favored political abilities, such as judgment, oratory, and persuasion, abilities to conceive and carry out complex plans, and skills in cooperative violence, including the evaluation of violent situations and the taking of calculated risks. It seems likely as well that in a milieu of complex, cooperative violence, selection would favor a male who was able to induce other males to take risks for his benefit. To these skills and abilities might be added: hunting-prowess, and capacities as seducer and/or lover.
Thus, as with most animal species, "At every moment in its game of life the masculine sex is playing for higher stakes" (Williams, 1975).
The evidence suggests, then, that for millions of years hominid males and females pursued substantially different reproductive 'strategies' and typically exhibited very different behaviors: throughout most of human evolutionary history, hunting, fighting, and that elusive activity, 'politics', were highly competitive, largely male domains. It is not a simple question of high female parental investment and male competition for females: males and females invested in different ways. Not only did males hunt while females gathered, but, if warfare was often over land and other scarce resources from which the winning males' offspring benefited, male fighting was in part parental investment; that is, like hunting and gathering, fighting and nurturing were part of the human division of labor by sex. Far more than in any other animal species, natural, sexual, and artificial selection were intertwined and perhaps inseparable during the course of human evolution (Symons, 1979).

An Existential-Validation Theory

Having established that the conduct of war is quintessentially a male occupation, Kroeber & Fontana (1987) provide an interesting psycho- social theory, which, they state, is rooted in the evolution of human culture. They point to the Neolithic revolution - the domestication of plants and animals - as a principal generator of warfare as a cultural institution. Before that time, males, as hunters and as gatherers who worked the distant perimeters of their group's territory, were essential partners in the maintenance of family and community life.
With the advent of farming, however, it became evident that women often could perform most or even all essential community chores: tend the hearth, bear and raise children, and plant, cultivate, and harvest the calories needed to stay alive. The worth of males, their dignity as human beings, their existential validation, was challenged to the utmost. A major response appears to have been a shift from man the hunter (and killer) to man the warrior (and killer).
While population increase, land-hunger, and accumulation of agricultural products have been proposed as tentative explanations for the tremendous upsurge of warfare in late Neolithic times, Kroeber & Fontana believe that a deeper reason - and one that might help explain the persistence of warfare as a modern phenomenon - may lie in the disequilibrium in the sex divisions of respected societal roles which resulted when males became less essential (or all but useless) as hunters and gatherers.
Kroeber & Fontana are not suggesting that warfare is a necessary result of agriculture. Fabbro's (1978) list of peaceful societies attests to this. Other male statuses than that of 'warrior' might adequately substitute for those of hunter and far-wandering gatherer in sedentary societies. Indeed, it is less likely that 'agriculture' is the key concept than 'sex division of labor', 'sex division of valued status positions' or 'sex division of energy allocation'. Whatever the forces may be causing severe maladaptation in this relationship, be they farming, animal husbandry, equestrian nomadism, intensive fishing, or other economic activities, it is the imbalance in the relationship that matters. Males had to revalidate their status as dignified human beings by becoming warriors.

Population control, preferential female infanticide, the male supremacist complex, and primitive war

A theory of population control in primitive society involving the effects of preferential female infanticide and warfare has been developed by Divale (1970 et seq.), Harris (1971 et seq.), and Divale & Harris (1976). The theory holds that every human society must take steps to control population growth. This is especially the case in primitive societies because their simpler technology places greater limits on their ability to expand food energy production. The manner in which most primitive societies regulate their population is postulated as follows: "Infanticide is practiced on both males and females for a variety of reasons. However, since there is a general preference to have a boy as the first child, and since the ratio of males and females at birth is almost equal, many more girl infants get killed. In terms of population control this is significant because excess females are eliminated before they reproduce. The effect of selective female infanticide is that many more boys reach maturity than do girls and a shortage of marriageable women exists among young adults. The women shortage leads to adultery, rape, and wife-stealing which in turn lead to frequent disputes over women. Deaths which result from these disputes lead to blood-revenge feuding and warfare in which the excess male population is eliminated. In the childhood generation boys greatly outnumber girls because of female infanticide. But in the adult generation the ratio between the sexes is balanced because males die in warfare. However, even though the adult ratio is about equal a relative women shortage still exists due to the practice of polygyny. The older and more influential males have several wives, leaving younger males wifeless. The constant warfare of these societies creates a constant need for warriors and it is this need which causes the cultural preference for a boy as the first child which begins the process in the first place.
The root of this entire system is a culturally produced women shortage. Female infanticide and polygyny create a shortage of women which leads to wars which in turn favor male infants, etc. The cycle is continuous and each generation creates conditions which perpetuate the process in succeeding generations. The next effect is the control of excess population" (Divale, 1974). There seems, according to the same author, to be a direct correlation between population density and the forms of violence (feuding, raiding, open battle) that occur. Bands of very low population densities, such as the Central Eskimo, practiced mostly feuding, conducted raids only infrequently and engaged in an open battle only once in a century. Among tribes which had a higher population density than bands, feuding was important, but took a second place to the raiding or war party type of warfare. Feuding was also the primary process through which groups fissioned or split apart. A feud within a village tended to split the village along lines of descent and marriage ties with the smaller faction usually moving away to found a new village. Even among the more densely populated fully tribal peoples, such as in highland New Guinea, feuds played a much smaller role than raids and battles. It is not suggested that war caused female infanticide, or that the practice of female infanticide caused war. Rather, it is proposed "that without reproductive pressure neither warfare nor female infanticide would have become widespread and that the conjunction of the two represents a savage but uniquely effective solution to the Malthusian dilemma" (Harris, 1978).

Furthermore, warfare functions in this system to sustain the so-called 'male supremacist complex' (social practices such as patrilocality, polygyny, marriage by capture, brideprice, postmarital sex restrictions on women, sexual hierarchy with female subordination, sexual privileges for fierce warriors, male machismo, masculine displays, dangerous and competitive sports and martial skills, militancy, the warrior cult; and in general war-linked, male-centered institutions, prerogatives and ideologies - because the survival of the group is contingent upon the rearing of combat-ready males) and thereby provide the practical exigencies and ideological imperatives for postpartum cultural selection against female infants (Divale & Harris, 1976). The males have a price to pay for all this: they constitute the bulk of the victims of warfare in preindustrial societies (Harris, 1975). Finally, the theory explains that peoples like the Yanomamö, Dani, Maring, and Maori attribute their wars to disputes over women. Although, Harris (1975) warns, such explanations cannot be accepted at face value; the belligerents who lose their lives in armed combat seldom accurately understand why they do so. "Excessive warfare is an ecological trap into which humanity has probably fallen again and again" (Harris, 1975). He concludes that "war has been part of an adaptive strategy associated with particular technological, demographic, and ecological conditions", but that this does not require us to "invoke imaginary killer instincts or inscrutable or capricious motives to understand why armed combat has been so common in human history" (Harris, 1974).

War and the Male Supremacist Complex (2)

There remains the question of how men are to be trained to be fierce and aggressive so that they will risk their lives in combat. Since the preference for rearing males over females means that there will be a shortage of women as marriage partners, one way to insure that men will be aggressive in combat is to make sex and marriage contingent on being a fierce warrior. Logically, one might suppose that the solution to the problem of a shortage of women would be to have several men share a wife, but actually polyandry is extremely rare. Indeed, just the opposite occurs: in prestate societies practicing warfare there is a strong tendency for men to take several wives, that is, to be polygynous. Thus, instead of sharing women, men compete for them, and the shortage of women is made even more severe by the fact that some men have two or three wives. This leads to much jealousy, adultery, and sexually charged antagonism between men and women, as well as hostility between men and men, especially junior 'have nones' and senior 'have severals' (Harris, 1980; Divale & Harris, 1976; 1978a,b; Divale et al., 1978; Cf. Howe, 1978; Lancaster & Lancaster, 1978; Norton, 1978).
Note that this theory relates the intensity of preindustrial male supremacist complex to the intensity of warfare and the intensity of reproductive pressures. It predicts that wherever the intensity of warfare and reproductive pressure are low, the male supremacist complex will be weak or virtually absent. This prediction conforms to the widely held view that many hunter-gatherer band societies had both low levels of warfare and high sexual parity or sexual autonomy, and that both warfare and sexual inequality increased with the development of agriculture and the state.
However, it also accounts for the reported occurrences of strong male supremacist complexes in warlike hunter-gatherer band societies as, for example, in Australia. Not all band societies confronted similar ecological conditions and similar degrees of reproductive pressure.
In short, wherever there is intense preindustrial warfare, groups that develop the male supremacist complex are likely to rout and displace groups that do not (Harris, 1980).

Masculinity, War, and the Oedipus Complex

The above explanation reverses the causal arrows in Freudian explanations of warfare. Freud regarded the aggressivity and sexual jealousy of males to be instinctual. He saw both war and the Oedipus complex as products of this aggressive instinct. There is much evidence, however, to indicate that the aggressive and sexually jealous male personality is itself caused by warfare, whereas warfare itself is caused by ecological and political-economic stresses.
Similarly, the Oedipus complex itself can be seen not as the cause of warfare, but as the consequence of having to train males to risk their lives in combat. Wherever the objective of child-rearing institutions is to produce aggressive, manipulative, fearless, virile, and dominant males, some form of sexually charged hostility between the junior and senior males is inevitable. But this does not mean that the Oedipus complex is an inevitable expression of human nature. Rather, it is a predictable outcome of training males to be combative and 'masculine' (Harris, 1980).

The theory exposed above has met some severe criticism, as far as it pretends to be a theory of the origin of primitive war, the causal role of preferential infanticide in this process, and the empirical evidence the authors marshall to corroborate the theory. In this context, however, it is more important to note that the theory envisages the possibility that the institution of war itself is the basis of the male supremacist complex, or that the two mutually and synergistically reinforced each other: the existence of war leading to warrior-type personalities, and the existence of warrior-type personalities leading to the continuation and further institutionalization of war practices.


In the foregoing I have discussed some theoretical considerations regarding the differentiation of the sexes in relation to early warfare: 'Krieg als Geslechtsphänomen' par excellence. One might object that these considerations are quite irrelevant to the contemporary situation: after all, a modern soldier is not a primitive warrior. Furthermore, women have been successfully integrated in the military institutions, not only in supportive and administrative roles and functions, but actually as combat units: e.g. in the armies of Israel and Norway.
What the primitive warrior generally lacked was (a sense of) obedience and discipline. These are relatively late and recent - on the time scale of cultural evolution - developments. It is doubtful, however, whether these developments are for the better, because, as we know, obedience and discipline can rather easily be distorted (or hypertrophied) to the point of 'Kadaverdisziplin'.
There is furthermore evidence that women in the instrumental and agentive roles of e.g. terrorist, police officer, or concentration camp guard, approximate men in committing violent, destructive and cruel acts and other disengaged death-dealing behaviors. In these cases, the social role demands probably obfuscate whatever psychobiological sex differences might exist.

See my Origin of War (1995) for an extended evolutionary and selectionist explanation of why males are the warriors in humans ( Homo s. sapiens), as well as in common chimpanzees (Pan troglodytes).


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