Horgan. T., Broadbent, J., McKibbin, W.F., & Duehring, A. (2015). Show versus tell? The effects of mating context on women’s memory for a man’s appearance and speech. Journal of Social and Personal Relationships

 Show versus tell? The effects of mating context on women’s memory for a man’s appearance and speech.

Horgan. T., Broadbent, J., McKibbin, W.F., & Duehring, A.

 

in press.

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McKibbin, W.F., Miner, E.J., Shackelford, T.K., Ehrke, A.D., & Weekes-Shackelford, V.A. Men’s mate retention varies with men’s personality and their partner’s personality. Personality and Individual Differences, 56, 62-67.

Men’s mate retention varies with men’s personality and their partner’s personality.

McKibbin, W.F., Miner, E.J., Shackelford, T.K., Ehrke, A.D., & Weekes-Shackelford, V.A.

 

Mate retention is the recurrent adaptive problem of retaining a mate in a relationship. Humans may have evolved mechanisms which motivate behavior in response to this problem. We examined the relationship between men’s mate retention and men’s and their partner’s personality in studies of 467 men and 565 women in committed relationships. Participants reported on their own or their partner’s mate retention and both their own and their partner’s personality. Results indicate a negative relationship between men’s Emotional Stability and men’s mate retention and a positive relationship between men’s Agreeableness and men’s benefit-provisioning mate retention. Discussion addresses limitations and directions for future research addressing the links between personality and mate retention

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McKibbin, W.F. (2014). Evolutionary psychology and rape avoidance. In Weekes-Shackelford, V.A., & Shackelford, T.K. (Eds.), Evolutionary perspectives on human sexual psychology and behavior. New York: Springer.

Evolutionary psychology and rape avoidance.

William F. McKibbin

 

This chapter reviews the topic of women’s rape avoidance from a modern evolutionary psychological perspective (for an overview, see Confer et al., 2010).  Evolutionary psychology provides researchers with a powerful heuristic tool that can be used to generate new testable hypotheses across all domains of psychology.

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McKibbin, W.F., Pham, M.N., & Shackelford, T.K. (2013). Investigating human sperm competition in post-industrial ecologies: Cues to sperm competition predict pornographic DVD sales rank. Behavioral Ecology, 24, 819-823.

Investigating human sperm competition in post-industrial ecologies: Cues to sperm competition predict pornographic DVD sales rank.

McKibbin, W.F., Pham, M.N., & Shackelford, T.K.

 

Sperm competition theory has been used to generate the hypothesis that men prefer to view pornographic images suggesting the presence of a rival male, over images which do not. The current research uses a new methodology to address conflicting evidence about men’s preferences for pornographic images. Raters coded a random sample of 166 pornographic DVDs (from a population of 49 493), which were then analyzed using multiple regression. Consistent with the hypothesis generated from sperm competition theory, the number of images on a DVD cover and screenshots depicting 2 or more men interacting with 1 woman (suggesting the presence of sperm competition) predicts DVD sales rank, whereas the number of images on a DVD cover and screenshots depicting 2 or more women interacting with 1 man (suggesting the absence of sperm competition) does not predict DVD sales rank. Discussion addresses limitations and future directions, including using penile plethysmography to avoid relying on correlational analyses.

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McKibbin, W.F., & Shackelford, T.K. (2013). Comment on “Reexamining individual differences in women’s rape avoidance”, by Snyder and Fessler (2012). Archives of Sexual Behavior, 42, 1-4.

Comment on “Reexamining individual differences in women’s rape avoidance”, by Snyder and Fessler (2012).

William F. McKibbin and Todd K. Shackelford

 

Recently, Snyder and Fessler (in press) published in Archives of Sexual Behavior an article entitled “Reexamining individual differences in women’s rape avoidance”. This article was written in response to an article we published in Archives of Sexual Behavior (McKibbin, Shackelford, Miner, Bates, & Liddle, 2011). Snyder and Fessler (hereafter referred to as S&F)
criticized our work on both theoretical and empirical grounds. We thank these authors for their interest in our work. In this letter, we address their criticisms and problems associated with each criticism.

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McKibbin, W.F. (2013, February 17). Why do we orgasm at all? HuffPost TED Weekends. Retrieved from http://www.huffingtonpost.com/william-mckibbin/male-orgasm-research_b_2697390.html (Invited submission.)

Why do we orgasm at all?

William McKibbin.

 

Scientific study of the orgasm has revealed some fascinating results, as seen in Mary Roach’s TEDTalk. Her presentation is informative, titillating and to some perhaps scandalous. As a scientist who specializes in the study of sexual behavior, I especially appreciated her talk. But what drew me to science is my constant need to ask ‘why’. Why do people behave the way they do? What is the purpose or design in an anatomical or behavioral trait? Regarding orgasm, readers may be surprised to learn this is a hot debate.

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Starratt, V. G., McKibbin, W. F., & Shackelford, T. K. (2013). Experimental manipulation of psychological mechanisms responsive to female infidelity. Personality and Individual Differences, 55, 59-62.

Experimental manipulation of psychological mechanisms responsive to female infidelity.

Starratt, V. G., McKibbin, W. F., & Shackelford, T. K.

 

Recent research indicates that men may have evolved mechanisms dedicated to detecting and responding to the risk of partner infidelity. Because activation of these ‘‘anti-cuckoldry’’ mechanisms depends onpartner infidelity, or the perception of partner infidelity, existing evidence for suchmechanisms relies oncorrelational data. The current study tests several predictions regarding men’s anti-cuckoldry mecha-nisms in an experimental design. As predicted, the results demonstrated: (1a) experimental activation of men’s anti-cuckoldry mechanisms by presenting them with a vignette depicting a female partner’s sexual infidelity; (1b) no activation of men’s anti-cuckoldry mechanisms by presenting them with a vignette depicting a sexual encounter without female infidelity; (2) experimental activation of men’s anti-cuckoldry mechanisms was influenced by their perceived risk of partner infidelity; and (3) women wernot influenced by the partner infidelity manipulation.

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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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McKibbin, W.F., Bates, V.M., Shackelford, T.K., Hafen, C.A., & LaMunyon, C.W. (2010). Risk of sperm competition moderates the relationship between men’s satisfaction with their partner and men’s interest in their partner’s copulatory orgasm. Personality and Individual Differences, 49, 961-966

Risk of sperm competition moderates the relationship between men’s satisfaction with their partner and men’s interest in their partner’s copulatory orgasm

William F. McKibbin, Vincent M. Bates, Todd K. Shackelford,
Christopher A. Hafen, and Craig W. LaMunyon

 

Sperm competition occurs when the sperm of multiple males concurrently occupy a female’s reproductive
tract and compete for fertilization. Sperm competition may have been a recurrent adaptive problem over human evolutionary history (Shackelford & Pound, 2006). Women’s orgasm may facilitate selective uptake and retention of a particular man’s sperm (Thornhill & Gangestad, 2008). Men who are more satisfied with and invested in their relationship may experience greater costs in the event of sperm competition and potential cuckoldry. Therefore, these men may be especially interested in ensuring their partner’s copulatory orgasm. We hypothesized that men’s relationship satisfaction and investment would predict interest in their partner’s copulatory orgasm, and that sperm competition risk would moderate the association between relationship satisfaction and interest in partner’s copulatory orgasm. Using structural equation modeling on self-report data secured from 229 men in a committed heterosexual relationship, we tested and found support for these hypotheses.

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Swami, V., … McKibbin, W.F., et al. (2010). The attractive female body weight and female body dissatisfaction in 26 countries across 10 world regions: Results of the International Body Project I. Personality and Social Psychology Bulletin, 36, 309-325

The Attractive Female Body Weight and Female Body Dissatisfaction in 26 Countries Across 10 World Regions: Results of the International Body Project I

Viren Swami, David A. Frederick, Toivo Aavik, Lidia Alcalay, Jüri Allik, Donna Anderson, Sonny Andrianto, Arvind Arora, Åke Brännström, John Cunningham, Dariusz Danel, Krystyna Doroszewicz, Gordon B. Forbes, Adrian Furnham, Corina U. Greven, Jamin Halberstadt, Shuang Hao, Tanja Haubner, Choon Sup Hwang, Mary Inman, Jas Laile Jaafar, Jacob Johansson, Jaehee Jung, Askin Keser, Uta Kretzschmar, Lance Lachenicht, Norman P. Li, Kenneth Locke, Jan-Erik Lönnqvist, Christy Lopez, Lynn Loutzenhiser, Natalya C. Maisel, Marita P. McCabe, Donald R. McCreary, William F. McKibbin, Alex Mussap, Félix Neto, Carly Nowell, Liane Peña Alampay, Subash K. Pillai, Alessandra Pokrajac-Bulian, René T. Proyer, Katinka Quintelier, Lina A. Ricciardelli, Malgorzata Rozmus-Wrzesinska, Willibald Ruch, Timothy Russo, Astrid Schütz, Todd K. Shackelford, Sheeba Shashidharan, Franco Simonetti, Dhachayani Sinniah, Mira Swami, Griet Vandermassen, Marijke van Duynslaeger, Markku Verkasalo, Martin Voracek, Curtis K. Yee, Echo Xian Zhang, Xiaoying Zhang and Ivanka Zivcic-Becirevic

 

 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.

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Schützwohl, A., Fuchs, A., McKibbin W.F., & Shackelford, T.K. (2009). How willing are you to accept sexual requests from slightly unattractive to exceptionally attractive imagined requestors? Human Nature, 20, 282-293.

How Willing Are You to Accept Sexual Requests from Slightly Unattractive to Exceptionally Attractive Imagined Requestors?

Achim Schützwohl, Amrei Fuchs,
William F. McKibbin and Todd K. Shackelford

 

 In their classic study of differences in mating strategies, Clark and Hatfield (1989, Journal of Psychology and Human Sexuality, 2, 39–54) found that men and women demonstrated a striking difference in interest in casual sex. The current study examined the role of an imagined requestor’s physical attractiveness (slightly unattractive, moderately attractive, and exceptionally attractive) on men’s and women’s willingness to accept three different requests (go out, come to apartment, go to bed) as reflected in answers to a questionnaire. We tested two hypotheses with a sample of 427 men and 443 women from three countries. Hypothesis 1 states that men, relative to women, will demonstrate a greater willingness to accept the “come to apartment” and “go to bed” requests but not the “go out” request for all three levels of requestor attractiveness. This  hypothesis reflects Clark and Hatfield’s main findings. Hypothesis 2 states that the physical attractiveness of a potential partner will have a greater effect on women’s than on men’s willingness to accept all three requests, and particularly for the explicit request for casual sex. The results partially supported Hypothesis 1 and fully supported Hypothesis 2. The discussion highlights limitations of the current research and presents directions for future research.

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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. (2008). Review of Michael Pollan’s The Omnivore’s Dilemma. Human Ethology Bulletin, 23, 6-8.

 The Omnivore’s Dilemma: A Natural History of Four Meals
By Michael Pollan

Reviewed by William F. McKibbin & Todd K. Shackelford

Florida Atlantic University

The Omnivore’s Dilemma is the latest book by Michael Pollan, best known for his previous bestselling work, The Botany of Desire. Here, Pollan has crafted a well written and enjoyable exploration of humans’ relationship to food. The book is written for a lay audience, but is appreciable by all.

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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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Starratt, V. G., Goetz, A. T., Shackelford, T. K., McKibbin, W. F., & Stewart-Williams, S. (2008) Men’s partner-directed insults and sexual coercion in intimate relationships. Journal of Family Violence, 23, 315-323.

Men’s Partner-Directed Insults and Sexual Coercion in Intimate Relationships

Valerie G. Starratt & Aaron T. Goetz & Todd K. Shackelford & William F. McKibbin & Steve Stewart-Williams

Women who have been sexually coerced by an intimate partner experience many negative health consequences. Recent research has focused on predicting this sexual coercion. In two studies, we investigated the relationship between men’s use of partner-directed insults and sexually coercive behaviors in the context of intimate relationships. Study 1 secured self-reports from 247 men on the Partner-Directed Insults Scale and the Sexual Coercion in Intimate Relationships Scale. Study 2 obtained partner reports from 378 women on the same measures. Across both studies, results indicate that men’s use of sexually coercive behaviors can be statistically predicted by the frequency and content of the insults that men direct at their intimate partner. Insults derogating a partner’s value as a person and accusing a partner of sexual infidelity were most useful in predicting sexual coercion. The discussion notes limitations of the current research and highlights directions for future research.

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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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McKibbin, W. F., Goetz, A. T., Shackelford, T. K., Schipper, L., Starratt, V. G., & Stewart-Williams, S. (2007). Why do men insult their partners? Personality and Individual Differences, 43, 231-241.

Why do men insult their intimate partners?

William F. McKibbin a, Aaron T. Goetz a, Todd K. Shackelford a, Lucas D. Schipper a, Valerie G. Starratt a, Steve Stewart-Williams b

aFlorida Atlantic University
b McMaster University

 

Men sometimes insult their intimate partners and these insults predict intimate partner violence. No research has investigated the function of men’s partner-directed insults. We hypothesize that men’s partner-directed
insults are designed to retain their long-term mate and, therefore, that men’s use of partner-directed insults will covary with other mate retention behaviors. Using the mate retention inventory and the partner-directed insults scale, we conducted two studies to test this hypothesis. Study 1 included 245 men who reported their mate retention behaviors and partner-directed insults. Correlations and multiple regression analyses documented the predicted relationships between men’s partner-directed insults and mate retention behaviors. Study 2 included 372 women who reported their partner’s mate retention behaviors and insults that their partner-directed at them. The results replicated the results of Study 1. Discussion highlights future directions for investigating the relationships between men’s partner-directed insults and mate retention behaviors.

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Shackelford, T. K., Goetz, A. T., McKibbin, W. F., & Starratt, V. G. (2007). Absence makes the adaptations grow fonder: Proportion of time apart from partner, male sexual psychology, and sperm competition in humans. Journal of Comparative Psychology, 121, 214-220.

Absence Makes the Adaptations Grow Fonder: Proportion of Time Apart
From Partner, Male Sexual Psychology, and Sperm Competition
in Humans (Homo sapiens)

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

Florida Atlantic University

 

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.

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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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