This article presents evidence suggesting that sex differences in aggression are universal, but that the differences are also highly susceptible to experiential modification. Following a “phylogenetic perspective” that emphasizes the interaction of genotype and experience, the author finds that boys are on average more aggressive than girls but adult males as a group are not significantly more aggressive than women.

The author explicitly defines and provides code for male and female age organizations and secret societies in Africa, as well as their significant sociopolitical roles within society. The author conducts preliminary analysis using the codes to explore characteristics and regional patterns of such organizations and societies. The analysis is compared to existing studies in order to assess the code and better understand cross-cultural patterns and variances. The author identifies the usefulness of the code beyond Africa, and discusses avenues for future research. No explicit hypotheses were tested, but Ericksen includes some descriptive generalizations.

"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.

Heider's theory of cognitive balance is applied to Levi-Strauss' discussion of the sentiment relations existing among four kin roles.

This article suggests that Spiro's (1965) study on typology of social structure used a biased cross-cultural sample and possibly obscured regional patterns in data. Hypotheses related to marital structure, descent rules, food production and social stratification are tested.

In this chapter of 'Beyond War,' Douglas critiques previous codes of warfare to make a distinction between feuding and warring. A test of warfare and level of social complexity among hunter-gatherers is conducted. Results indicate that complex hunter-gatherers make war while a majority of simple hunter-gatherers do not.

This study provides a cross-cultural examination of the definitions of old age. Further research on these definitions and their implications is suggested.

This study tests several hypothesis about predictors of male or female gods. Results suggest a relationship between relative emphasis on female deities and rule of descent.

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

This article examines three theories regarding the existence of pollution rules. Results show support for a psychological theory put forward by Freud that predicts a relationship between father-child contact, post-partum sex taboos, and menstrual taboos.