Why Do Men Rape? An Evolutionary Psychological Perspective

Why Do Men Rape? An Evolutionary Psychological Perspective | Aaron Goetz - Academia.edu

"We propose five types of rapists (or contexts of rape), (1) disadvantaged men who resort to rape, (2) “specialized” rapists who are sexually aroused by violent sex, (3) men who rape opportunistically, (4) high-mating-effort men who are dominant and often psychopathic, and (5) partner rapists motivated by assessments of increased risk of sperm competition. We next discuss evidence for each type of rapist.

The first hypothesized rapist type includes men who are motivated to rape if they have no other means of securing copulations. This may be referred to as the disadvantaged male hypothesis. This hypothesis also has been referred to as the mate deprivation hypothesis (Lalumie ´re, Chalmers, Quinsey, & Seto, 1996). It is supported by data indicating that rapes are committed disproportionately by men with low socioeconomic status (Kalichman, Williams, Cherry, Belcher, & Nachimson, 1998; Thornhill & Thornhill, 1983). Furthermore, Krill, Lake, and Platek (2006) presented evidence that men convicted of rape display lower facial symmetry, an indicator of poor genetic quality. Facial symmetry is linked positively with physical and psychological health (Shackelford & Larsen, 1997), and men with lower facial symmetry are perceived as less attractive and as less desirable mates (Gangestad & Thornhill, 1999; Gangestad, Thornhill, & Yeo, 1994). Deprived of mates by normal means, some men may resort to rape...

Another type of rapist may be the specialized rapist... Because rape carries high potential costs for the rapist, particularly if caught in the act, rapists with a psychology that motivated quicker arousal and ejaculation during rape might have been more successful than men who did not possess such a psychology (Thornhill & Palmer, 2000).

Support for the existence of this hypothesized group has been generated by investigating whether men are aroused by depictions of rape versus depictions of casual sex. Meta-analyses indicate that convicted rapists demonstrate greater sexual arousal to scenes of sexual coercion involving force than do nonrapists (Hall, Shondrick, & Hirschman, 1993; Lalumiere & Quinsey, 1994; Thornhill & Thornhill, 1992)...

Thornhill and Palmer (2000) have hypothesized that some rapists may be capable of producing a high-sperm-count ejaculate that would increase the chance of fertilization. Men seem to be capable of unconsciously adjusting sperm number in ejaculates, such as in response to a greater risk of sperm competition (Baker & Bellis, 1989, 1993), but it is unknown whether rapists adjust sperm numbers during rape...

There is indirect evidence corroborating the hypothesis that rapists’ ejaculates are more competitive than nonrapists. Gottschall and Gottschall (2003) estimated that pregnancy rates resulting from rape are two times that of consensual per-incident rates. That is, approximately 6% of rapes result in pregnancy compared to approximately 3% of consensual copulations...

Burch and Gallup (2006) hypothesized that men may have an adaptation that functions to adjust semen chemistry to cause ovulation immediately following a rape...

The third hypothesized rapist type is the opportunistic rapist... The universality of laws and societal norms prohibiting rape (wife rape being a special exception; see below) indicates an appreciation that men are more likely to rape when the costs are low (Palmer, 1989; Thornhill & Palmer, 2000). The fact that rapes regularly occur during wartime has been presented as evidence of the assessment of victim vulnerability and decreased likelihood of detection (e.g., Gottschall, 2004)...

Women with family members, particularly adult male family members, living nearby are much less likely to be physically assaulted by their partner (Figueredo et al., 2001; Kanin, 1957). This suggests that potential rapists are attending to the probability of retaliation by a victim’s adult male family members.

A fourth hypothesized rapist type is the highmating- effort rapist. High-mating-effort rapists, in contrast to other types, such as disadvantaged rapists, appear to be more sexually experienced (Lalumiere & Quinsey, 1996). These rapists may be characterized as aggressive, dominant, and having high self-esteem. Such rapists often may be characterized as psychopathic (Lalumiere, Harris, Quinsey, & Rice, 2005). Lalumiere et al. argue that high mating effort is an important facet of psychopathy. They argue that although most men appear to deploy mating strategies according to environmental contexts, psychopathic men deploy a high-mating-effort strategy in most contexts, pursuing many partners with little investment, and using coercion and rape when noncoercive tactics fail...

Research evidence corroborates the plausibility of this rapist type. Dean and Malamuth (1997), for example, found that men who scored high on a Sexual Experience measure, “were more likely to report sexual coercion if they were also self-centered as opposed to nurturant”... Lalumiere and Quinsey (1996) found that a strong indicator of past sexual coercion is positive self-perceived mating success and an extensive history of casual sexual relationships. Finally, the risk of date rape is greater when the man initiated the date, spent money on the woman, and provided transportation (Muehlenhard & Linton, 1987). Perceived relative deprivation, in which an individual’s (high) expectations about having sex are not satisfied (Malamuth et al., 2005) also may play a role in the sexually coercive behavior of high-matingeffort men. For example, men who report a greater likelihood of committing rape tend to endorse statements expressing an increased perception of mate deprivation, but do not report an overall fewer number of sexual opportunities...

A final hypothesized rapist type includes men motivated to rape their partners under conditions of increased sperm competition risk... most likely to occur when a man learns or suspects that his long-term partner recently has been sexually unfaithful...

Women are particularly likely to be raped by their partner during a breakup instigated by men’s concerns about their partner’s infidelity (Thornhill & Palmer, 2000)...

Men are more aroused by and prefer sexually explicit images that suggest the occurrence of sperm competition than by sexually explicit images that do not suggest the occurrence of sperm competition (Kilgallon & Simmons, 2005; Pound, 2002). Furthermore, men who spend a greater proportion of time apart from their partners since the couple’s last copulation (and therefore face a higher risk of sperm competition) report that they find their partner more attractive, are more interested in copulating with their partner, and believe that their partner is more interested in copulating with them (Shackelford, Goetz, McKibbin, & Starratt, 2007; Shackelford et al., 2002). These results are independent of relationship satisfaction, total time since last copulation, and total time spent apart...

Goetz and Shackelford (2006) documented in two studies that men’s sexually coercive behavior is positively related to their partner’s infidelities, that is, to the risk of sperm competition. Men with partners who committed infidelities, or who suspected that their partner had committed infidelities (indicating increased risk of sperm competition), were more likely to perform sexually coercive behaviors, including rape. These findings are consistent with the existence of psychological mechanisms that motivate men to commit partner rape in response to risk of sperm competition...

Aside from death, perhaps the greatest cost to women who are raped is the circumvention of their mate choice. This is because anything that circumvents women’s choice in mating can severely jeopardize their reproductive success (Symons, 1979).

Researchers have speculated that a variety of female traits evolved to reduce the risks of being raped. Smuts (1992) argued that women form alliances with groups of men and other women for protection against would-be rapists. Wilson and Mesnick (1997) proposed and found support for the bodyguard hypothesis: Women’s mate preferences for physically and socially dominant men may reflect antirape adaptation. Of course, women may form alliances or prefer dominant mates for reasons other than to avoid rape. Alliances offer protection from such dangers as assault or predation, and dominant mates may possess higher-quality genes, for example. Davis and Gallup (2006) proposed the intriguing possibility that preeclampsia and spontaneous abortion may be adaptations that function to terminate pregnancies not in the woman’s best reproductive interests, such as those resulting from rape...

Reproductive age women are hypothesized to experience more psychological pain due to the greater risk of conception. Thornhill and Thornhill (1990a) documented support for this hypothesis, documenting that reproductive-age women are more traumatized by rape than are postreproductive-age women or prereproductive-age girls...

Petralia and Gallup (2002) examined whether a woman’s capacity to resist rape varies across the menstrual cycle. Women in the fertile phase of their menstrual cycle showed an increase in handgrip strength, but only when presented with a sexual coercion scenario...

Research documented a significant decrease in performance of risky behaviors by women in the fertile phase of their menstrual cycle. This evidence is consistent with the hypothesized function of rapeavoidance mechanisms, particularly when women are fertile...

Women in the fertile phase of their menstrual cycle rated the men as more sexually coercive. This suggests that women at greater risk of conception may be more attuned to signs of male sexual coerciveness than women at lesser risk of conception. This may represent an evolved cognitive error management bias (see Haselton, Nettle, & Andrews, 2005, for an overview) towards identifying men as sexually coercive, which might serve to protect women from being raped"