Females' tendency to place a high value on protecting their own lives enhanced their reproductive success in the environment of evolutionary adaptation because infant survival depended more upon maternal than on paternal care and defence. The evolved mechanism by which the costs of aggression (and other forms of risk taking) are weighted more heavily for females may be a lower threshold for fear in situations which pose a direct threat of bodily injury. Females' concern with personal survival also has implications (...) for sex differences in dominance hierarchies because the risks associated with hierarchy formation in nonbonded exogamous females are not offset by increased reproductive success. Hence among females, disputes do not carry implications for status with them as they do among males, but are chiefly connected with the acquisition and defence of scarce resources. Consequently, female competition is more likely to take the form of indirect aggression or low-level direct combat than among males. Under patriarchy, men have held the power to propagate images and attributions which are favourable to the continuance of their control. Women's aggression has been viewed as a gender-incongruent aberration or dismissed as evidence of irrationality. These cultural interpretations have evolutionarily based sex differences by a process of imposition which stigmatises the expression of aggression by females and causes women to offer exculpatory (rather than justificatory) accounts of their own aggression. (shrink)

Children may be viewed as public goods whereby both parents receive equal genetic benefits yet one parent often invests more heavily than the other. We introduce a microeconomic framework for understanding household investment decisions to address questions concerning conflicts of interest over types and amount of work effort among married men and women. Although gains and costs of marriage may not be spread equally among marriage partners, marriage is still a favorable, efficient outcome under a wide range of conditions. This (...) bioeconomic framework subsumes both cooperative and conflictive views on the sexual division of labor. We test hypotheses concerning marriage markets, assortative mating, and men’s labor motivations among Tsimane forager-horticulturalists of Bolivia and find that: (1) men and women both value work effort in marital partners, (2) marital labor contributions are complementary, (3) work effort is correlated between spouses, (4) total production is correlated with total reproduction, and (5) better hunters have higher fitness gains within marital unions. (shrink)

This text addresses the profound human questions of love and work. Beginning with a historical introduction, the author progresses through adaptive problems that humans face, and concludes by showing how evolutionary psychology encompasses all branches of psychology.

In two large samples, we found a positive relationship between disgust sensitivity and political conservatism. This relationship held when controlling for a number of demographic variables as well as the “Big Five” personality traits. Disgust sensitivity was also associated with more conservative voting in the 2008 U.S. presidential election. In Study 2, we replicated the disgust sensitivity–conservatism relationship in an international sample of respondents from 121 different countries. Across both samples, contamination disgust, which reflects a heightened concern with interpersonally transmitted (...) disease and pathogens, was most strongly associated with conservatism. (shrink)

Evolutionary approaches to the emotions have traditionally focused on a subset of emotions that are shared with other species, characterized by distinct signals, and designed to solve a few key adaptive problems. By contrast, an evolutionary psychological approach (a) broadens the range of adaptive problems emotions have evolved to solve, (b) includes emotions that lack distinctive signals and are unique to humans, and (c) synthesizes an evolutionary approach with an information-processing perspective. On this view, emotions are superordinate mechanisms that evolved (...) to coordinate the activity of other programs in the solution of adaptive problems. We illustrate the heuristic value of this approach by furnishing novel hypotheses for disgust and sexual arousal and highlighting unexplored areas of research. (shrink)

Few people realize how much science can tell us about the differences between men and women. Yves Christen, provided the first comprehensive overview of research in this area when this classic book was first published in the1990s. He goes beyond simplistic “biology is destiny” arguments and constructs a convincing case for linking social and biological approaches in order to understand complex differences in behavior. Biologists agree that the sexes differ in brain and body structure. Christen links these differences in cerebral (...) anatomy to differences in behavior and intellect. Taking his readers on a journey through psychology, endocrinology, demography, and many other fields, Christen shows that the biological and the social are not antagonistic. To the contrary, social factors tend to exaggerate the biological rather than neutralize it. This controversial work, Sex Differences, takes on traditional feminism for its refusal to confront the evidence on biologically determined sex differences. Christen argues for a feminism that sees traits common to women in a positive light, in the tradition of such early feminists as Clemence Royer and Margaret Sanger, as well as more contemporary feminist sociobiologists like Sarah Hrdy. We deny sex differences only at the price of scientific truth and our own self-respect. (shrink)

In evolutionary psychology predictions, women’s mate preferences shift between fertile and nonfertile times of the month to reflect ancestral fitness benefits. Our meta-analytic test involving 58 independent reports (13 unpublished, 45 published) was largely nonsupportive. Specifically, fertile women did not especially desire sex in short-term relationships with men purported to be of high genetic quality (i.e., high testosterone, masculinity, dominance, symmetry). The few significant preference shifts appeared to be research artifacts. The effects declined over time in published work, were limited (...) to studies that used broader, less precise definitions of the fertile phase, and were found only in published research. (shrink)