Textor summarizes cross-cultural findings on extramarital sexual relations pertaining to cultural, environmental, psychological, and social phenomena.

Textor summarizes cross-cultural male initiation rites findings pertaining to cultural, environmental, psychological, and social phenomena.

The authors examine a world-wide sample of cultures to assess whether the romantic-sexual kiss is a human universal. They also test for an association between romantic-sexual kissing and social complexity.

This study examines ecological, social, and psychological theories for men's fear of heterosexual sex in a cross-cultural sample. Findings support the hypotheses and a causal model is presented.

This paper is concerned with the variation in sexual behavior in humans. Authors test hypotheses regarding the relationships between sexual behaviors and beliefs concerning sex.

Focusing on 61 preindustrial societies that have information on fertility, the author asks what factors may explain variation in fertility, what devices are used to control fertility, and whether differences in fertility appear to be in line with the societies' environments.

The author attempts to test the "Oedipus-complex" hypothesis--the psychoanalytic idea that under certain conditions (such as the long-post partum sex taboo) males are sexually attracted to their mothers and as a consequence certain fears and anxiety are generaated. The hypothesis is tested at the societal-level using ethnographic data.

This study looks at the relationship between the presence of love magic in a society and sexual anxiety. Results show support for the hypothesis that love magic is positively correlated with sexual anxiety.

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.

In order to evaluate an adaptive justification for restriction of ritualized physical contact, the authors test association between three manifestations of physical interaction and prevalence of pathogens cross-culturally. Their expectation, supported by two of the three tested hypotheses, is that higher pathogen prevalence will lead to customs of restricted physical contact. Both cultural and biological evolution are suggested to be influential in selecting for physically intimate behaviors.