Biosocial Construction of Sex Differences and Similarities in Behavior

Abstract

The behavior of women and men varies greatly depending on situations, cultures, and historical periods. This flexibility emerges as men and women tailor their division of labor to local ecological and socioeconomic demands. The resulting division is supported by childhood socialization practices that, in interaction with sex differences in child temperament, help boys and girls to develop psychologies suited to their likely adult activities. Although responsive to local conditions, the division of labor is constrained by women's childbearing and nursing of infants and men's size and strength. Because these biological characteristics influence the efficient performance of many activities in society, they underlie central tendencies in the division of labor as well as its variability across situations, cultures, and history. Gender roles—that is, shared beliefs about the traits of women and men—track the division of labor because people infer these traits from their observations of the sexes’ behaviors. Social perceivers often essentialize these traits by regarding them as inherent in the biology or social experience of women and men. Gender role expectations, which tend to be consensual within cultures, influence behavior through proximal social psychological and biological processes, whereby (a) other people encourage gender-typical behavior and individuals conform to their own gender identities and (b) hormonal, reward, and cardiovascular mechanisms enable masculine and feminine behaviors.

Introduction

In asking, “Why can't a woman be more like a man?” Professor Higgins in “My Fair Lady” (1964) was drawing on his knowledge of female and male behavior in British Victorian society. In that society, as in all other known societies, men and women differed in their daily activities and presumably in their psychological dispositions. Yet, if Professor Higgins had been savvier about world cultures, then he would have known that sometimes, a woman is more like a man. That is, women have undertaken masculine activities under many circumstances. In some nonindustrialized societies, for example, women have served in combat troops (e.g., Alpern, 1998) and as large game hunters (e.g., Goodman, Griffin, Estioko-Griffin, & Grove, 1985). In industrialized societies, large numbers of women have entered occupations such as attorney and manager that were once dominated by men (e.g., U.S. Bureau of Labor Statistics, 2011, Table 11).

Professor Higgins did not inquire why a man cannot be more like a woman. Yet, a man sometimes is like a woman because he undertakes activities that are considered feminine in the great majority of societies. For example, in some hunter-gatherer societies, most fathers perform substantial infant care (Fouts, 2008, Gettler, 2010). In many industrialized societies, some men pursue female-dominated occupations such as nurse and social worker, and others are stay-at-home dads or secondary wage earners whose wives serve as main breadwinner (Sayer et al., 2004, U.S. Bureau of Labor Statistics, 2011, Tables 11 and 25).

The evidence that men and women sometimes engage in gender-atypical activities suggests a flexible psychology that is not rigidly differentiated by sex. Flexibility refers not to random variation of behavior, but to the capacity to vary behaviors to enable reproduction and survival under changeable situational demands. For example, both sexes can be socially sensitive or aggressive, given appropriate socialization and support from social normative, self-regulatory, and hormonal processes. This responsiveness to cultural and situational demands arises from humans’ evolved capacities to innovate and share information with others and thereby to produce a cumulative culture in which beliefs and practices are shared and subsequently modified (Richerson and Boyd, 2005, Tennie et al., 2009). This flexibility is organized by a collaborative division of labor between the sexes that varies in form across societies. In this chapter, after briefly explaining the origins of the division of labor, we elaborate the psychological processes by which it organizes the behavior of men and women within societies.

The division of labor is evident in the specific activities performed by men and women in a society. As shown in Fig. 2.1, this division emerges flexibly given two sets of causes: (a) the cultural, socioeconomic, and ecological environment in which people live and (b) the distinctive physical attributes of women and men, especially women's reproductive activities and men's size and strength (Eagly and Wood, 2012, Wood and Eagly, 2002, Wood and Eagly, 2010). Because of the physical specialization of the sexes, some activities in a given environment are more efficiently performed by one sex or the other. For example, women's childbearing and nursing facilitate infant care in most societies and conflict with many other activities, especially those that require specialized training and other extended absences from home. The physical attributes that underlie divided labor reflect evolutionary pressures on human ancestors, as does the flexibility with which this division shifts to correspond to humans’ contemporaneous conditions. This behavioral flexibility is enabled by the sophisticated cognitive abilities of the evolved hominin brain.

Within societies, the division of labor sets in place a cascade of psychological and social processes. These processes, in turn, stabilize the current division by making it seem sensibly tailored to the attributes of women and men. Thus, people infer the traits of men and women from observing their behaviors, and they generally regard these traits as intrinsic to each sex. For example, if women care for children, they are thought to be nurturing and caring, and if men fight wars, they are thought to be tough and brave. Such gender role beliefs, shared within a society, promote socialization practices that encourage children to gain the skills, traits, and preferences that support their society's division of labor. Gender roles encourage most adults to conform to these shared beliefs by confirming others’ expectations and by internalizing them as personal standards for their behavior. In addition, biological processes such as hormonal activation support gender role behaviors. By this confluence of biosocial processes, individuals within a society dynamically construct gender in patterns that are tailored to their time, culture, and situation.

As this brief description of our theory implies, the causes of male and female behavior range from more proximal, or immediate, to more distal, or ultimate. In Fig. 2.1, the more distal causes appear above the division of labor and the more proximal appear below.

Our biosocial constructionist account offers a sharp contrast to evolutionary psychology theories, which attribute sex-related differences to the activation of predetermined behavioral repertoires (see Buss & Schmitt, 2011). In these alternative evolutionary theories, sex differences emerge in domains in which women and men experienced different selection pressures in evolutionary history. According to this view, current social and cultural contexts serve simply as triggers to activate particular preformed responses. In contrast, in our biosocial construction model, sex differences and similarities in behavior emerge from the division of labor in a society, which itself is a product of social and cultural forces in interaction with the biological features characteristic of each sex. In this chapter, we explain this model and review research that supports it, with special emphasis on the research that we have contributed.