After studying Paiute society, the author postulates that sorcery may serve as a mechanism for social control in societies lacking superordinate authority justice. In this chapter, the cross-cultural results were presented.

The Trivers-Willard hypothesis posits that concentrations of human milk immune factors vary with maternal condition (maternal diet diversity and body mass index) and the sex of the infant. Using linear mixed-effects models to analyze 358 milk samples from 10 international sites, the authors find minimal support for the Trivers-Willard hypothesis; only one immune factor, IgG, exhibited a significant relationship.

This paper supports Beatrice B. Whiting's (1965) sex-identity conflict hypothesis which suggests a relationship between males' early identification with their mothers and male violence. Authors find that, in addition to socialization aggression, frequency of homicide/assault is significantly related to father-infant sleeping distance, particularly when residence is not matrilocal and/or warfare is more than occasional.

This study examines husband-wife relationships, specifically rooming and sleeping arrangements, as they relate to variables such as infant care, subsistence, residence, and cultural complexity. Several hypotheses are tested and all are supported.

This study explores ecological reasons that might explain why boys are mostly circumcised in tropical regions, particularly in Africa and the insular Pacific. The author postulates a long causal chain linking: 1) tropical climate to the growing of root and fruit crops; 2) the need to keep babies on mother's milk for as long as possible where the adult diet is lacking in protein; 3) a long post-partum sex taboo as a way to space births; 4) the practice of polygyny (and associated mother-child sleeping) in the face of a long sex taboo; 5) patrilocal residence; and 6) male initiation ceremonies which are believed to result from the combination of mother-child sleeping, the long poast-partum sex taboo and patrilocal residence.

This study examines the relationship between adult male height and mother-infant separation. Results indicate that males who are separated from their mothers briefly during infancy are taller in adulthood than those who are not.

This study is a continuation of previous research on the relationship between stress during infancy and adult height. With a better understanding of the stressors that infants experience and their effects, the authors test whether the relationship between stress and adult height remains significant when accounting for other environmental factors that may influence adult height. Results suggest that the relationship between infant stress and adult height does remain significant. Findings also show a relationship between infant stress and age at menarche.

In previous studies, researchers have observed an increased growth rate in rats that experienced stimulation during infancy. This study examines the relationship between stressful experiences during infancy and adult male stature in humans cross-culturally. Results suggest a strong positive relationship between infant stress and adult male stature.

This study advances the status envy hypothesis of sex identification to explain customs such as male initiation ceremonies and the couvade. Theory of sex identification is discussed; resource withholding, exclusive mother-child sleeping, patrilocality, father absence, female status, and initiation are all considered. Hypotheses are supported with empirical tests.