Perceived risk of female infidelity moderates the relationship between objective risk of female infidelity and sexual coercion in humans (Homo sapiens).

Female extrapair copulation (EPC) can be costly to a woman's long-term romantic partner. If a woman has copulated recently with a man other than her long-term partner, her reproductive tract may contain the sperm of both men, initiating sperm competition (whereby sperm from multiple males compete to fertilize an egg). Should the woman become pregnant, her long-term partner is at risk of cuckoldry-investing unwittingly in offspring to whom he is not genetically related. Previous research in humans (Homo sapiens) and in nonhuman animals suggests that males have evolved tactics such as partner-directed sexual coercion that reduce the risk of cuckoldry. The current research provides preliminary evidence that mated men (n = 223) at greater risk of partner EPC, measured as having spent a greater proportion of time apart from their partner since the couple's last in-pair copulation, more frequently perform partner-directed sexually coercive behaviors. This relationship is moderated, however, by men's perceived risk of partner EPC, such that the correlation between the proportion of time spent apart since last in-pair copulation and sexually coercive behaviors remains significant only for those men who perceive themselves to be at some risk of partner EPC. Discussion addresses limitations of this research and highlights directions for future research investigating the relationship between female EPC and men's partner-directed sexual coercion.

Individual differences in women's rape avoidance behaviors.

Rape can exact severe psychological, physical, and reproductive costs on women, and likely was a recurrent adaptive problem over human evolutionary history. Therefore, women may have evolved psychological mechanisms that motivate rape avoidance behaviors. Guided heuristically by an evolutionary perspective, we tested the hypothesis that women's rape avoidance behaviors would vary with several individual difference variables. Specifically, we predicted that rape avoidance behaviors would covary positively with (1) women's attractiveness, (2) women's involvement in a committed romantic relationship, and (3) the number of family members living nearby. We also predicted that women's rape avoidance behaviors would covary negatively with age. We administered the Rape Avoidance Inventory (McKibbin et al., Pers Indiv Differ 39:336-340, 2009) and a demographic survey to a sample of women (n = 144). The results of correlational and regression analyses were consistent with the predictions, with the exception that women's rape avoidance behaviors did not covary with women's age. Discussion highlighted limitations of the current research and directions for future research on women's rape avoidance psychology and behaviors.

The attractive female body weight and female body dissatisfaction in 26 countries across 10 world regions: results of the international body project I.

This study reports results from the first International Body Project (IBP-I), which surveyed 7,434 individuals in 10 major world regions about body weight ideals and body dissatisfaction. Participants completed the female Contour Drawing Figure Rating Scale (CDFRS) and self-reported their exposure to Western and local media. Results indicated there were significant cross-regional differences in the ideal female figure and body dissatisfaction, but effect sizes were small across high-socioeconomic-status (SES) sites. Within cultures, heavier bodies were preferred in low-SES sites compared to high-SES sites in Malaysia and South Africa (ds = 1.94-2.49) but not in Austria. Participant age, body mass index (BMI), and Western media exposure predicted body weight ideals. BMI and Western media exposure predicted body dissatisfaction among women. Our results show that body dissatisfaction and desire for thinness is commonplace in high-SES settings across world regions, highlighting the need for international attention to this problem.

Absence makes the adaptations grow fonder: proportion of time apart from partner, male sexual psychology, and sperm competition in humans (Homo sapiens).

Sperm competition occurs when the sperm of multiple males concurrently occupy the reproductive tract of a female and compete to fertilize an egg. We used a questionnaire to investigate psychological responses to the risk of sperm competition for 237 men in committed, sexual relationships. As predicted, a man who spends a greater (relative to a man who spends a lesser) proportion of time apart from his partner since the couple's last copulation reported (a) greater sexual interest in his partner, (b) greater distress in response to his partner's sexual rejection, and (c) greater sexual persistence in response to his partner's sexual rejection. All effects were independent of total time since the couple's last copulation and the man's relationship satisfaction. Discussion addresses limitations of the current research and situates the current results within the broader comparative literature on adaptation to sperm competition.