Authors investigate the prevalence of male homosexual preference (MHP) cross-culturally. They employ four models to test the link between level of social stratification and the probability of observing male homosexual preference (MHP). Authors believe that this link supports the hypergyny hypothesis, which proposes that increased social stratification allows for some sort of factor that improves functional female fertility, perhaps through marriage to men of higher social classes. This would thereby allow more access to resources and consequently the ability to support a greater number of more reproductively-successful offspring. Authors do not make a causal link, however; rather, social stratification may be associated with a yet-undetermined pleiotropic factor that is somehow positive despite its cost on functional male fertility.

This book discusses the characteristics of adolescence cross-culturally and examines the differences in the adolescent experience for males and females. Several relationships are tested in order to gain an understanding of cross-cultural patterns in adolescence.

This study argues that different types of homosexuality must be examined separately. Authors focus on mentorship and pathic homosexual behavior and test factors that are associated with these two types of behavior.

This study explores the extent to which heterosexual sex, love, and intimacy are interrelated and the degree to which the sexual revolution has had a positive or negative impact on male-female relationships. The author employs a correlation matrix to examine the interrelationships of several variables related to aloofness and intimacy in the sexual and non-sexual aspects of heterosexual relationships. Results suggest that the sexual revolution has had some positive effects on male-female relationships, but also that sexual behavior does not predict the degree to which marriages are intimate or aloof. Results also show little support for the hypothesis that marital aloofness is related to hypermasculinity.

This study tests predictions of homosexuality. Results suggest that homosexuality is significantly associated with father-son contact.

Researchers sampled 48 societies cross-culturally to study the genetic survival of male homosexual preference, which is argued to be deleterious in nature due to its fertility costs. The researchers test for a sexually antagonistic factor that would produce a pleotropic advantage, such as male homosexual preference increasing the reproduction of sisters. Utilizing theoretical models, researchers assert that the survival of male homosexual preference is a result of the positive association between social stratification and discriminate female hypergyny due to selection for attractiveness in females.

This book chapter builds on Horton's 1943 psychoanalytical study of drunkenness. The author tests an overall theory that drunkenness, which facilitates personal and uninhibited interactions, is more acceptable, and therefore prevalent, in societies with loose, rather than rigid, social relationships. Indicators of social rigidity, such as strict socialization or male dominance through patrilocality, are tested for relationships to drunkenness.

"The kin selection hypothesis posits that male androphilia evolved because androphilic males invest more in kin, thereby enhancing inclusive fitness." However, increased kin-directed altruism has only been seen in societies that exhibit transgendered male androphilia. To test the validity of the kin selection hypothesis for male androphilia, the authors examine the relationship between ancestral sociocultural conditions, access to kin, and societal reactions to homosexuality and the expression of male androphilia as transgendered or non-transgendered. They find that ancestral sociocultural conditions and bilateral and double descent systems were more common in transgendered than non-transgendered societies.

This article examines institutionalized male transvestism and the couvade, finding that they are mutually exclusive in a cross-cultural sample. Possible explanations for the negative association between male transvestism and the couvade (e.g. sex-identity differentiation and confusion) are discussed.

This study seeks to better understand different forms of leadership across non-WEIRD (Western, Educated, Industrialized, Rich, and Democratic) societies, and tests evolutionary theories regarding the qualities of leaders, their functions, and the costs and benefits they incur and provide as a part of their leadership. The authors assess the various aspects of leaders and leadership by coding 109 dimensions of leadership as represented in eHRAF World Cultures, using the Probability Sample Files, comprised on 60 cultures. By assessing the prevalence of each of these dimensions in the various cultures under consideration, the authors were able to ascertain some largely universal characteristics of leaders: that they 1) were judged intelligent and knowledgeable; 2) resolved conflicts; and 3) received material and social benefits. They also found that other dimensions varied by considerably group context (e.g., kin group leaders tended to be older), subsistence strategy (e.g., hunter-gatherer leaders tend to lack coercive authority), and gender (e.g., female leaders are more associated with family contexts). Further analyses showed that followers and leaders both benefited from leadership, and that shamans constitute a new brand of leader that both utilizes prestige and dominance in order to effectively rule.