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.

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.

This study focuses on spousal responses to extramarital affairs cross-culturally. Results suggest that men and women are equally concerned with the sexual activities of their spouses, however, tactics used in response to infidelity vary by gender. Results also show a relationship between social complexity and responses to infidelity.

This study focuses on spousal responses to extramarital affairs cross-culturally. Results suggest that men and women are equally concerned with the sexual activities of their spouses, however, tactics used in response to infidelity vary by gender. Results also show a relationship between social complexity and responses to infidelity.

This study examines the variation in responses to sexual infidelity and the effect of social complexity and descent on responses to infidelity. Results suggest significant relationships between social complexity, descent, and responses to infidelity

This study examines the variation in responses to sexual infidelity and the effect of social complexity and descent on responses to infidelity. Results suggest significant relationships between social complexity, descent, and responses to infidelity

This study tests several hypotheses that men and women are differentially invested in their partner's sexual fidelity. Using a cross-cultural sample authors analyze women's and men's responses to sexual infidelity.

This study tests several hypotheses that men and women are differentially invested in their partner's sexual fidelity. Using a cross-cultural sample authors analyze women's and men's responses to sexual infidelity.

This study documents the phenomenon of the 'femme fatale' (a dangerous woman) and 'status fatale' (a dangerous man) cross-culturally. The 'femme fatale' motif is practically universal. Data supports the idea that emotional involvement, rather than sexual gratification, was the primary motivation for seeking out a stranger of the opposite sex. A literature review is provided.

This study documents the phenomenon of the 'femme fatale' (a dangerous woman) and 'status fatale' (a dangerous man) cross-culturally. The 'femme fatale' motif is practically universal. Data supports the idea that emotional involvement, rather than sexual gratification, was the primary motivation for seeking out a stranger of the opposite sex. A literature review is provided.