Wendy Wood and Alice H. Eagly
A Cross-Cultural Analysis of the Behavior of Women and Men:
Implications for the Origins of Sex Differences
Psychological Bulletin, 2002, Vol. 128, No. 5, 699–727
(read this paper)

This article evaluates theories of the origins of sex differences in human behavior. It reviews the cross-cultural evidence on the behavior of women and men in nonindustrial societies, especially the activities that contribute to the sex-typed division of labor and patriarchy. To explain the cross-cultural findings, the authors consider social constructionism, evolutionary psychology, and their own biosocial theory. Supporting the biosocial analysis, sex differences derive from the interaction between the physical specialization of the sexes, especially female reproductive capacity, and the economic and social structural aspects of societies. This biosocial approach treats the psychological attributes of women and men as emergent given the evolved characteristics of the sexes, their developmental experiences, and their situated activity in society.

The research that we have reviewed reveals that a universal feature of nonindustrial societies is a sex-typed division of labor or coordination between men and women in the performance of daily life tasks. This division is evident in that, within societies, the majority of tasks were performed primarily by one sex. However, which sex performed a particular task varied substantially across societies. The allocation of specific tasks across societies appears to be flexible, with the majority of tasks not uniquely associated with one sex. Yet, across societies some activities were almost always performed by men (e.g., hunting of large animals), and other activities were almost always performed by women (e.g., cooking of vegetal food).

The data also revealed systematic patterns of sex-typed contributions to subsistence and child care. Although men on the average contributed more to subsistence than women in nonindustrial societies, women contributed a substantial amount (e.g., Aronoff & Crano, 1975, estimated 44%). Furthermore, the relative contributions of the sexes varied with the local ecology, and women contributed more than men in societies dependent primarily on gathering. For child care, mothers predominated in the care of infants, but they substantially shared the care of young children with others in the family and the community. Fathers contributed to child care more than to infant care, but their contributions were almost universally less than those of mothers (Crano & Aronoff, 1978).

This is a review of literature related to cross-cultural comparisons of Sex Differences in behavior and develops the Biosocial theory to explain certain aspects of division of labor that seem nearly universal.

According to our biosocial analysis, consistency across societies should be found in the performance of activities most closely enabled or constrained by sex-typed physical attributes and reproductive activities. In this view, sex-differentiated social arrangements emerge because women’s childbearing and nursing of infants enable them to efficiently care for very young children and cause conflict with roles requiring extended absence from home and uninterrupted activity. Similarly, men’s greater speed and upper-body strength facilitate their efficient performance of tasks that require intensive bursts of energy. Thus, the cross-cultural pattern of each sex’s activities should reflect women’s reproductive roles and men’s size and strength.

The biosocial analysis also anticipates considerable variability in sex-typed activities. In this view, sex-typed behavior emerges from the efforts of biologically specialized individuals to maximize the rewards and minimize the costs of the outcomes available to them within a particular society and local ecology. Specifically, behavioral sex differences should vary systematically across cultures with societal and ecological conditions that diminish or enhance the impact of reproduction on women’s activities or of size and strength on men’s activities. For example, in societies that practice early supplemental feeding of infants, women should be freed to perform some tasks characteristic of men in other societies.

From this biosocial perspective, patriarchal social structures reflect the fit between the biological specialization of the sexes and the activities that yield status within a society. To the extent that men and women are biologically specialized to efficiently perform different activities, the sex that can more readily perform the activities that yield status and power is advantaged in a gender hierarchy. Thus, patriarchy is not a uniform feature of human societies but instead emerges to the extent that, for example, women’s reproductive activities conflict with the behaviors that yield status in a society. Finally, given the cross-cultural variability in sex differences that is anticipated by our biosocial model, it is likely that extensive socialization is required to orient boys and girls to function differently insofar as they are expected to occupy different social roles within their society.

This describes a mechanism where cultural similarities in gender roles are created by convergent Cultural Evolution. See also convergent evolution. Another way to put this is that some aspects of gender roles, such as maternal child care and male hunting are forced moves in cultural evolution. Commonalities exist not because nothing else is possible, but because nothing else works nearly as well. The immediate cause of the behavior difference is cultural, but culture is indirectly constrained by human nature.

The idea of a forced_move in cultural evolution is a coherent and plausible mechanism to explain any kind of cultural similarities, and is not new in this paper. We believe that this mechanism probably does operate to some degree, but reject the view that this paper seems to implicitly endorse: “Men and women have no differences other than the obvious physical and reproductive ones.” We believe there are both strong theoretical reasons and some pretty good evidence that men and women have some innate differences in their thought processes, motivations and mental aptitudes. See Sex Differences.