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., 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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McKibbin, W. F., Shackelford, T.K., Goetz, A.T., Bates, V.M. Starratt, V.G., & Miner, E.J. (2009). Development and Initial Psychometric Assessment of the Rape Avoidance Inventory. Personality and Individual Differences, 39, 336-340.

 Development and initial psychometric assessment of the
rape avoidance inventory

William F. McKibbin, Todd K. Shackelford, Aaron T. Goetz, Vincent M. Bates,
Valerie G. Starratt, Emily J. Miner

 

 Rape is a traumatic event with severe consequences for women. Therefore, women may have evolved
psychological mechanisms that motivate them to avoid circumstances linked with rape. We present the development and initial psychometric assessment of an inventory designed to assess women’s rape avoidance behaviors. In Study 1 (N = 99), we conducted an act nomination procedure to identify specific behaviors for inclusion in a preliminary rape avoidance inventory. In Study 2 (N = 144), we secured performance reports for the behaviors assessed by the inventory. We present the results of principal components analyses and the construction of the rape avoidance inventory (RAI). We identified four components of women’s rape avoidance behaviors as assessed by the RAI: avoid strange men, avoid appearing sexually receptive, avoid being alone, and awareness of surroundings/defensive preparedness. We demonstrate that, as predicted, performance of rape avoidance behaviors is negatively associated with a measure of interest in and pursuit of short-term sex. We conclude that the RAI is a useful tool for future research on rape avoidance and rape prevention

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Buss, D. M., Shackelford, T. K., & McKibbin, W. F. (2008). The Mate Retention Inventory-Short Form (MRI-SF). Personality and Individual Differences, 44, 322-334.

 The Mate Retention Inventory-Short Form (MRI-SF)

David M. Buss a, Todd K. Shackelford b, William F. McKibbin b

  University of Texas, Austin
Florida Atlantic University

 People devote considerable effort to retaining their mates. Mate retention tactics range from vigilance to
violence, and are linked to variables such as marital satisfaction and relationship aggression. The Mate
Retention Inventory (MRI; 104 items comprising 19 tactics) has proven to be reliable and valid. Given
the importance of assessing mate retention in various contexts, there is a need for a briefer version of
the MRI. In Study 1 (N = 1032), we develop a short form of the MRI (the MRI-SF), which assesses performance
of 19 mate retention tactics using two items per tactic. The tactic scales show internal consistency,
high correlations with the MRI long-form tactic scales, and links with assessments of controlling behavior,
relationship violence, and an assessment of injury. Study 2 (N = 625) replicates the MRI-SF reliability and
high correlations with the MRI long-form tactic scales, and shows links to a sexual coercion measure. We
conclude that the MRI-SF is sufficiently reliable and valid that it can be used in basic and applied research
in place of the MRI long-form for most purposes.

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Goetz, A. T., Shackelford, T. K., Starratt, V. G., & McKibbin, W. F. (2008). Intimate partner violence. In J. D. Duntley & T. K. Shackelford (Eds.), Evolutionary forensic psychology (pp. 65-78). New York: Oxford University Press.

 Intimate Partner Violence

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

 The theory of evolution by natural selection revolutionized the study of biology. So too is it revolutionizing the study of human psychology and behavior. Charles Darwin himself predicted, “Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history” (1859, p. 488). Modern evolutionary psychological perspectives have been used to predict and understand a diverse array of human behaviors, such as altruism, mating, and violence. In the past few decades, many psychologists have begun to recognize the value of using an evolutionary perspective to guide their research. With a focus on evolved mechanisms and associated information-processing features, evolutionary psychology has risen as a powerful heuristic tool for the study of human psychology and behavior. Evolutionary psychology leads researchers to look at old phenomena in a different light. Such a new perspective potentially offers powerful insights into human psychology and behavior. In this chapter, we use the tools provided by evolutionary theory to explore why violence and abuse occur between intimate partners. Specifically, we focus our discussion on physical and sexual intimate partner violence.

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McKibbin, W. F., Shackelford, T. K., Goetz, A.T., & Starratt, V. G. (2008) Evolutionary psychological perspectives on rape. In J. Duntley and T. K. Shackelford (Eds.), Evolutionary forensic psychology. (pp. 101-120). New York: Oxford University Press.

 Evolutionary Psychological Perspectives on Rape

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

…This chapter reviews the topic of rape from a modern evolutionary psychological perspective (see, e.g., Barkow, Cosmides, & Tooby, 1992; Buss, 2004). Evolutionary psychology is a powerful heuristic tool that can be used to generate new, testable hypotheses across all domains of psychology. Evolutionary psychology rests on several key premises (Buss, 2004). The fi rst premise states that natural selection is the only known process capable of producing complex functional systems such as the human brain. The complexity of human behavior can only be understood completely by taking into account human evolutionary history and natural selection. Second, behavior depends on evolved psychological mechanisms . These are information-processing mechanisms housed in the brain that register and process specific information and generate as output specific behaviors, physiological activity, or input relayed to other psychological mechanisms. Third, evolved psychological mechanisms are functionally specialized to perform a specific task or to solve a specific problem that recurrently affected reproductive success over evolutionary history. This premise is often referred to as domain specificity . Finally, the numerousness premise states that human brains consist of many specific evolved psychological mechanisms that work together to produce behavior. Together with a number of other theoretical tools and heuristics provided by modern evolutionary theory, these premises are used to generate evolutionary theories of psychology and behavior.

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McKibbin, W.F., Shackelford, T. K., Goetz, A. T., & Starratt, V. G. (2008). Why do men rape? An evolutionary psychological perspective. Review of General Psychology, 12, 86-97.

Why Do Men Rape? An Evolutionary Psychological Perspective

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

Florida Atlantic University

Rape of women by men has occurred throughout recorded history and across cultures. In this article, we discuss rape from an evolutionary psychological perspective. Evolutionary psychology is a powerful heuristic tool that allows researchers to develop and test novel hypotheses about complex behaviors such as rape. Some researchers have argued that men have evolved psychological mechanisms that motivate them to rape in specific contexts. We discuss evidence consistent with this claim, and argue that a more nuanced view of men’s rape behavior is necessary. We propose that it may be useful to characterize rapists as belonging to one of several types, distinguished by individual differences as well as by the circumstances in which they are predicted to commit rape. We discuss research evidence in support of each rapist type, as well as the need for future research. Finally, we discuss
research concerning women’s rape-avoidance psychology and behavior.

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Goetz, A. T., Shackelford, T. K., Platek, S. M., Starratt, V. G., & McKibbin, W. F., (2007). Sperm competition in humans: Implications for male sexual psychology, physiology, anatomy, and behavior. Annual Review of Sex Research, 18, 1-22.

Sperm Competition in Humans: Implications for Male Sexual Psychology, Physiology, Anatomy, and Behavior

Aaron T. Goetz, California State University – Fullerton
Todd K. Shackelford, Florida Atlantic University
Steven M. Platek, University of Liverpool, UK
Valerie G. Starratt, Florida Atlantic University
William F. McKibbin, Florida Atlantic University

 

With the recognition afforded by evolutionary science that female infidelity was a recurrent feature of our evolutionary past has come the development of a new area of study within human mating: sperm competition. A form of male-male postcopulatory competition, sperm competition occurs when the sperm of two or more males concurrently occupy the reproductive tract of a female and compete to fertilize her ova. Just as males must compete for mates, if two or more males have copulated with a female within a sufficiently short period of time, the sperm from different males will compete for fertilizations. In the 2 decades since Smith (1984) first argued that sperm competition occurs in humans, this theory has been enriched with new ideas and discoveries. We review the recent theoretical and empirical work on human sperm competition, identify limitations and challenges of the research, and highlight important directions for future research.

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Starratt, V. G., Shackelford, T. K., Goetz, A. T., & McKibbin, W. F., (2007). Male mate retention behaviors vary with risk of sperm competition. Acta Psychologica Sinica, 39, 523-527

Male mate retention behaviors vary with risk of sperm competition.

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

Florida Atlantic University

 

Sperm competition occurs when the sperm of two or more males concurrently occupy the reproductive tract of a single female and compete to fertilize an egg. This can be costly if the woman’s social partner loses the competition and, as a consequence, invests in offspring that are not genetically his own, a situation known as cuckoldry. Previous research suggests that men may have evolved tactics such as mate retention behaviors that reduce the risk of sperm competition and cuckoldry. The current research provides new evidence that men at greater risk of partner infidelity and sperm competition, measured as having spent a greater proportion of time apart from their partner since the couple’s last in-pair copulation, more frequently perform a variety of mate retention behaviors, such as calling unexpectedly to check up on their partners, monopolizing their partners’ time when around other men, and threatening other men who show an interest in their partners

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