McKibbin, W. F., & Shackelford, T.K. (2011). Women’s avoidance of rape. Aggression and Violent Behavior, 16, 437-443.

Women’s avoidance of rape

William F. McKibbin and Todd K. Shackelford


Females of many species have recurrently faced the adaptive problem of rape over the species’ evolutionary
history. In humans, rape of women by men has occurred throughout recorded history and across cultures, and exacts on women severe psychological, physical, and reproductive costs. Women therefore may have evolved psychological mechanisms that motivate rape avoidance behaviors. We provide an overview of recent theoretical and empirical research addressing women’s rape avoidance psychology and behavior from an evolutionary perspective. This research indicates that women may possess evolved mechanisms that motivate rape avoidance. We conclude by highlighting several directions for research that may further clarify the design features of human female evolved mechanisms that motivate rape avoidance

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McKibbin, W.F., Shackelford, T.K., Miner, E. J., Bates, V. M., & Liddle, J. R. (2011). Individual differences in women’s rape avoidance behaviors. Archives of Sexual Behavior, 40, 343-349.

Individual Differences in Women’s Rape Avoidance Behaviors

William F. McKibbin, Todd K. Shackelford, Emily J. Miner, Vincent M. Bates & James R. Liddle


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.

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McKibbin, W. F., Starratt, V. G., Shackelford, T. K., & Goetz, A. T. (2011). Perceived risk of female infidelity moderates the relationship between objective risk of female infidelity and sexual coercion in Humans (Homo sapiens). Journal of Comparative Psychology, 125, 370-373.

Perceived Risk of Female Infidelity Moderates the Relationship Between Objective Risk of Female Infidelity and Sexual Coercion in Humans (Homo sapiens)

William F. McKibbin, Valerie G. Starratt, Todd K. Shackelford, and Aaron T. Goetz


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.

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