Homosexual Mating Preferences from an Evolutionary Perspective: Sexual Selection Theory Revisited

Studies in evolutionary psychology and sexual selection theory show that heterosexual men prefer younger mating partners than heterosexual women in order to ensure reproductive success. However, previous research has generally not examined differences in mating preferences as a function of sexual orientation or the type of relationship sought in naturalistic settings. Given that homosexual men seek partners for reasons other than procreation, they may exhibit different mating preferences than their heterosexual counterparts. Moreover, mating preferences may show important differences depending on whether an individual is seeking a long-term versus a short-term relationship. The purpose of the present study was to examine these issues by comparing partner preferences in terms of age and relationship type between homosexual and heterosexual men placing internet personal advertisements. Participants included 439 homosexual and 365 heterosexual men who placed internet ads in the U.S. or Canada. Ads were coded for the participant’s age, relationship type (longer-term or short-term sexual encounter) sought, and partner age preferences. Significantly more homosexual than heterosexual men sought sexual encounters, although men (regardless of sexual orientation) seeking sexual encounters preferred a significantly wider age range of partners than men seeking longer-term relationships. These findings suggest that partner preferences are independent of evolutionary drives to procreate, since both types of men preferred similar ages in their partners. In addition, they highlight the importance of examining relationship type in evolutionary studies of mating preferences, as men’s partner preferences show important differences depending upon the type of relationship sought.     

Patterns of Sexual Arousal in Homosexual,Bisexual, and Heterosexual Men

The purpose of this study was to determine if self-identified bisexual, heterosexual, and homosexual men show differential genital and subjective arousal patterns to video presentations of bisexual, heterosexual, male homosexual, and lesbian sexual interactions. It was predicted that, relative to heterosexual and homosexual stimuli, bisexual men would show the highest levels of sexual arousal to bisexual erotic material, while this stimulus would induce relatively low levels of response in heterosexual and homosexual men. A sample of 59 men (19 homosexual, 13 bisexual, and 27 heterosexual) were presented with a series of 4-min sexual videos while their genital and subjective sexual responses were measured continuously. Bisexual men did not differ significantly in their responses to male homosexual stimuli (depicting men engaging in sex) from homosexual men, and they did not differ significantly in their responses to heterosexual (depicting two women, without same-sex contact, engaged in sex with a man) and lesbian (depicting women engaging in sex) stimuli from heterosexual men. However, bisexual men displayed significantly higher levels of both genital and subjective sexual arousal to a bisexual stimulus (depicting a man engaged in sex with both a man and a woman) than either homosexual or heterosexual men. The findings of this study indicate that bisexuality in men is associated with a unique and specific pattern of sexual arousal.     

男男性接触者中异性爱者与素质性同性爱者艾滋病高危性行为比较

目的探讨中国男男性接触者（MSM）中异性爱者与素质性同性爱者（gay）艾滋病高危性行为状况。方法采用定向抽样方法，对9城市2250例MSM进行匿名问卷调查，比较其中异性爱组与gay组的高危性行为。结果异性爱组累计同性性伴数（平均13．8个）、近6个月同性性伴数（平均3．8个）、累计同性口交性伴数（平均10．5个）和同性肛交性伴数（平均12．4个），均低于gay组；在婚异性爱组累计女性性伴数（平均4．9个）、近6个月女性性伴数（平均1．7个），均高于在婚gay组。异性爱组同性性交安全套使用率（68．8％）低于gay组；但最近1次同性肛交安全套使用率（91．3％）、与女性性交安全套使用率（63．7％）均高于gay组；两组最近1次同性肛交安全套使用率（分别为91．3％、71．0％）均高于最近1次同性口交安全套使用率。异性爱组最近1年曾参加群交百分率（9．9％）、性交时自己或对方出血过百分率（16．7％）、到外地并与当地男性性交百分率（11．4％），曾向同性买性百分率（4．6％）、16岁前遭遇过成年男性实施的强迫性交百分率（4．2％），均低于gay组。结论MSM中异性爱者与gay的高危性行为存在诸多差异，为有效阻断HIV传播，干预工作应选择重点亚人群进行。     

Sex in Australia: homosexual experience and recent homosexual encounters

OBJECTIVE: To describe the prevalence and features of homosexual experience and recent homosexual encounters among a representative sample of Australian adults. METHODS: Computer-assisted telephone interviews were completed by a representative sample of 10,173 men and 9,134 women aged 16-59 years from all States and Territories. The overall response rate was 73.1% (69.4% among men and 77.6% among women). RESULTS: Overall, 8.6% of women and 5.9% of men reported some homosexual sexual experience in their lives (p<0.001); these figures fell to 5.7% and 5.0% respectively (p=0.106) when non-genital sexual experience was excluded. 1.9% of men and 1.5% of women reported homosexual experience in the past year. Men who reported homosexual experience reported more same-sex partners than did women (means 31.6 and 3.2, p<0.001), and men and women who identified as homosexual or bisexual reported more sexual partners in total than those who identified as heterosexual. Respondents reporting homosexual experience were significantly more likely to be from an English-speaking background, have higher levels of education, live in a major city, and report a white-collar or managerial/professional occupation. Women who reported homosexual experience were less likely to have a middle or high income. In the most recent homosexual encounter, genital touching was the most commonly reported practice, and oral sex was reported much more frequently than in heterosexual encounters. CONCLUSION: Homosexually and bisexually identified men and women had higher total numbers of partners than heterosexuals. Improved societal attitudes towards homosexuality are likely to lead to further increases in estimates of the prevalence of homosexual experience in the community.     

Does sexual abuse in childhood cause pedophilia: An exploratory study

The reliability of the notion that pedophilia is caused by sexual abuse in childhood was explored by examining retrospective self-reports of 344 males. Included in the study were 77 heterosexual pedophiles, 54 homosexual pedophiles, 51 nonpedophilic sex offenders against children, 36 sex offenders against physically mature females, 75 heterosexual paid volunteers who erotically preferred mature females, and 51 homosexual clients who preferred mature males. For each sex offender the differential diagnosis of an erotic preference for minors vs. a preference for physically mature partners was made by means of the phallometric test of erotic gender and age preferences. The analysis of self-reports confirmed that the proportion of pedophiles who report having been sexually abused in childhood by mature persons is larger than that of men who were not charged for or accused of a sex offense against a child though the difference is relatively small (28.6 vs. 13.9 and 10.7% for the heterosexual pedophiles and the two groups of gynephiles, respectively, and 25.9 vs. 11.8% for the homosexual pedophiles and androphiles, respectively). Further analysis demonstrated, however, that pedophiles who admitted having an erotic interest in children significantly more often claimed that they had been sexually abused as children than pedophiles who did not admit having such feelings. This interdependence renders the reliability of these self-reports questionable.This research was supported in part by grant MA-9134 from the Medical Research Council of Canada.Forensic Division Clarke Institute of Psychiatry     

Sex-Specificity in the Reward Value of Facial Attractiveness

Studies of the sex-specificity of sexual arousal in adults (i.e., the tendency to respond more strongly to preferred-sex individuals than non-preferred sex individuals) have suggested that heterosexual men, homosexual men, and homosexual women show stronger sex-specific responses than do heterosexual women. Evidence for a similar pattern of results in studies investigating the reward value of faces is equivocal. Consequently, we investigated the effects of (1) sexual orientation (homosexual vs. heterosexual), (2) sex (male vs. female), (3) image sex (preferred-sex vs. non-preferred-sex), and (4) the physical attractiveness of the individual shown in the image on the reward value of faces. Participants were 130 heterosexual men, 130 homosexual men, 130 heterosexual women, and 130 homosexual women. The reward value of faces was assessed using a standard key-press task. Multilevel modeling of responses indicated that images of preferred-sex individuals were more rewarding than images of non-preferred-sex individuals and that this preferred-sex bias was particularly pronounced when more physically attractive faces were presented. These effects were not qualified by interactions involving either the sexual orientation or the sex of our participants, however, suggesting that the preferred-sex bias in the reward value of faces is similar in heterosexual men, homosexual men, heterosexual women, and homosexual women.     

Sexual Orientation Differences in Cerebral Asymmetry and in the Performance of Sexually Dimorphic Cognitive and Motor Tasks

With each of the tasks in the present studies we expected to find the reported sex difference between heterosexual women and heterosexual men and we predicted a sexual orientation effect with the performance of homosexual men being similar to that of heterosexual women and different from that of heterosexual men. Study I aimed to replicate earlier findings by recording the performance of a group of homosexual men on a visuospatial task, the Vincent Mechanical Diagrams Test (VMDT), a dot detection divided visual field measure of functional cerebral asymmetry, and on five subtests of the Wechsler Adult Intelligence Scale (WAIS). For each task the profile of scores obtained for the homosexual men was similar to that of heterosexual women in that they scored lower than heterosexual men on the VMDT, they showed less asymmetry, and they recorded a higher Verbal than Performance IQ on the WAIS. In Study 2, a male-biased targeted throwing task favored heterosexual men while, in contrast, on the female-biased Purdue Pegboard single peg condition heterosexual men were outperformed by heterosexual women and homosexual men. On neither of these two tasks did the performances of homosexual men and heterosexual women differ. One task, manual speed, yielded neither sex nor sexual orientation differences. Another, the Purdue Pegboard assemblies condition, revealed a sex difference but no sexual orientation difference. Failure to obtain a sexual orientation difference in the presence of a sex difference suggests that the sexual orientation effect may be restricted to a subset of sexually dimorphic tasks.     

Self-Reported Sexual Desire in Homosexual Men and Women Predicts Preferences for Sexually Dimorphic Facial Cues

Recent studies investigating the relationship between self-reported sexual desire and attraction to same- and opposite-sex individuals have found that homosexual men’s sexual desire is positively correlated with their self-reported attraction to own-sex individuals only, while homosexual women’s sexual desire is positively correlated with their self-reported attraction to both men and women. These data have been interpreted as evidence that sexual desire strengthens men’s pre-existing (i.e., dominant) sexual behaviors and strengthens women’s sexual behaviors in general. Here we show that homosexual men’s (n = 106) scores on the Sexual Desire Inventory-2 (SDI-2) were positively correlated with their preferences for exaggerated sex-typical shape cues in own-sex, but not opposite-sex, faces. Contrary to the hypothesis that sexual desire strengthens women’s preferences for sexual dimorphism generally, homosexual women’s (n = 83) SDI-2 scores were positively correlated with their preferences for exaggerated sex-typical shape cues in opposite-sex faces only. Together with previous research in heterosexual subjects, our findings support the proposal that sexual desire increases the incidence of existing sexual behaviors in homosexual and heterosexual men, and increases the incidence of sexual responses more generally in heterosexual women, although not necessarily in homosexual women.     

The number of recent sex partners among bisexual men in the United States

CONTEXT: Little is known regarding bisexual men’s number of recent sex partners, a risk factor for HIV and other STDs. Furthermore, it is unclear if bisexual men have more partners than heterosexual or homosexual men, and whether partner number varies by measures of sexual behavior, identity and attraction. METHODs: Sexual orientation—defined separately by sexual behavior during the past year, identity and attraction—was assessed for 3,875 sexually active men aged 15–44 who had participated in the 2002 National Survey of Family Growth. Chi‐square and t tests examined differences in background characteristics, behavioral risk factors and number of past‐year sex partners by sexual orientation according to each definition. Multivariate ordinary least‐squares regression was used to assess predictors of the number of partners. RESULTS: When sexual identity and attraction were controlled for, behaviorally bisexual men were predicted to have had 3.1 more past‐year partners than behaviorally heterosexual men and 2.6 more than behaviorally homosexual men. After controlling for sexual identity and behavior, bisexual‐attracted men had had 0.7 fewer partners than homosexual‐attracted men. In a model including background characteristics and behavioral risk factors, behaviorally bisexual men were predicted to have had 2.5–2.6 more partners than others. Neither bisexual identity nor bisexual attraction independently predicted the number of recent partners. CONCLUSION: The way in which bisexuality relates to men’s number of recent sex partners depends on how sexual orientation is measured. Interventions to reduce behaviorally bisexual men’s number of partners will likely lessen their risk for HIV and other STDs.     

Feminine gender identity and physical aggressiveness in heterosexual and homosexual pedophiles

This study explored the differences among six groups of adult males in retrospective self-reports of childhood gender identity and physical aggressiveness. The three groups of homosexual men preferred prepubescent, pubescent, or physically mature sexual partners. The three groups of heterosexual men preferred prepubescent partners, normal sexual interaction with physically mature partners (controls), or anomalous interaction with physically mature partners. Childhood gender identity was measured with the Feminine Gender Identity Scale (FGIS), and boyhood aggressiveness was measured with the Physical Aggressiveness Scale (PAS). Duncan tests at the .05 level showed that the FGIS differentiated the homosexuals who preferred mature partners from the five other groups; whereas the PAS differentiated all homosexual groups from all heterosexual groups. These results suggest that male homosexuals in general tend to be unaggressive in boyhood, whereas only those who prefer mature sexual partners show significant levels of feminine identification.     

Mate Retention Behavior of Men and Women in Heterosexual and Homosexual Relationships

Comparing the behavior of heterosexual and homosexual persons can provide insight into the origins of heterosexual sex differences in psychology. Evidence indicates that, aside from sexual partner preference, the mating psychology of homosexual men is sex-typical whereas that of homosexual women tends to be more sex-atypical. The current study examined one aspect of mating psychology, mate retention behavior, and tested whether homosexual men and women were sex-typical or sex-atypical for those mate retention tactics where heterosexual men and women differed. Men and women in heterosexual and homosexual relationships were asked to provide information regarding their partners' mate retention behavior by using the Mate Retention Inventory Questionnaire. Heterosexual men and women differed significantly for six of the 19 mate retention tactics considered. With respect to the six mate retention tactics where heterosexual sex differences existed, homosexual men behaved in a sex-typical manner for five of the tactics, whereas homosexual women behaved in a sex-atypical manner for all six tactics. We discuss the significance of these findings for explaining the origins of the mate retention behavior of heterosexual men and women. In addition, we consider what the pattern of sex-typical and sex-atypical mating psychology among homosexual men and women, respectively, suggests in regard to sex differences in the development of mating psychology and the development of homosexual persons.     

The Emergence of Lesbian Sexuality and Identity Cross-Culturally: Brazil, Peru, the Philippines, and the United States

Questionnaire data were collected from 205 lesbians and 224 heterosexual women in Brazil, Peru, the Philippines, and the United States between 1981 and 1988. Items include direction of childhood sexual interests, age of first awareness of sexual attraction, cross-attractions, age of first sexual contact, sex of partner in first sexual contact, age of awareness that sexual attractions were serious, and age of realization of adult sexual orientation. In general, similarities in the development of lesbian sexuality and differences between lesbians and heterosexual women were found, regardless of culture. Findings include: Lesbians were more sexually active as children and displayed more sexual interest in girls than heterosexuals did in boys; lesbians tended to become aware of their attractions to women later than heterosexuals realized attractions to men; lesbians reported considerably more early attraction to men than heterosexuals did to women; lesbians reported earlier sexual contact than did heterosexual women; the sex of the partner of first sexual contact for lesbians was split roughly equally between males and females whereas heterosexuals reported contact with males almost exclusively; childhood awareness that sexual attractions were serious were similar in lesbians and heterosexuals; lesbians defined themselves as homosexual later than heterosexuals defined themselves as heterosexual. We conclude that norms for heterosexual behavior impact the development of lesbian sexuality and identity, impeding, but not obliterating,their development. Lesbian sexualityand identityeventuallyemerge regardless of culture.     

The Cognitive, Behavioral, and Personality Profiles of a Male Monozygotic Triplet Set Discordant for Sexual Orientation

The neurohormonal theory of sexual orientation proposes that homosexual men and homosexual women are exposed prenatally to a hormonal environment that is similar to that of the other sex. Prenatal exposure to an opposite-sex hormonal environment may lead the nervous system to develop in a manner consistent with the opposite sex. If this cross-sex exposure occurs, one prediction would be that the cognitive ability profile of homosexual men would be similar to that of heterosexual women. This study examined a set of male monozygotic triplets, aged 21 years, discordant for sexual orientation: 2 of the triplets were heterosexual, 1 was homosexual. The triplets were administered measures of 23 domains of cognitive ability, as well as measures of sexual orientation and masculinity/femininity. On the measures of cognitive ability, the triplets performed similarly, yet consistent differences were found between the 2 heterosexual triplets and the 1 homosexual cotriplet. Differences having the same pattern were found for the number of Schafer homosexuality signs on the Rorschach, and on a homosexuality scale derived from items on the Minnesota Multiphasic Personality Inventory--2 (MMPI-2). Responses from the homosexual triplet were in a more feminine direction than responses from his 2 heterosexual cotriplets on measures of masculinity-femininity, which included measures derived from Rorschach responses, the MMPI-2 Masculinity-Femininity scale, the Bem Sex Role Inventory, and the Boyhood Gender Conformity Scale. Responses to the 16 Personality Factor Questionnaire also distinguished the 1 homosexual triplet from the 2 heterosexual cotriplets. These findings support the view that the prenatal hormonal environment may have enduring effects on selected behavioral traits.     

Handedness,sexual orientation,and gender-related personality traits in men and women

This study assessed large numbers of heterosexual and homosexual men and women on handedness and gender-related personality traits. Initial analyses employed a dichotomous measure of handedness (right-handed vs. non–right-handed). For men and women combined, homosexual participants had 50% greater odds of being non–right-handed than heterosexual participants, a statistically significant difference. Homosexual men had 82% greater odds of being non–right-handed than heterosexual men, a statistically significant difference, whereas homosexual women had 22% greater odds of being non–right-handed than heterosexual women, a nonsignificant difference. When participants were classified into five graduated categories of handedness, both men and women showed significant homosexual–heterosexual differences in handedness distributions. Within groups, handedness showed a number of weak but statistically significant associations with sex-typed occupational preferences, self-ascribed masculinity, and self-ascribed femininity, but not with instrumentality or expressiveness. Rates of non–right-handedness were virtually identical for heterosexual men and women, suggesting that sex differences in handedness may result from higher rates of homosexuality in men.     

Upset Over Sexual versus Emotional Infidelity Among Gay,Lesbian, Bisexual,and Heterosexual Adults

One hypothesis derived from evolutionary perspectives is that men are more upset than women by sexual infidelity and women are more upset than men by emotional infidelity. The proposed explanation is that men, in contrast to women, face the risk of unwittingly investing in genetically unrelated offspring. Most studies, however, have relied on small college or community samples of heterosexual participants. We examined upset over sexual versus emotional jealousy among 63,894 gay, lesbian, bisexual, and heterosexual participants. Participants imagined which would upset them more: their partners having sex with someone else (but not falling in love with them) or their partners falling in love with someone else (but not having sex with them). Consistent with this evolutionary perspective, heterosexual men were more likely than heterosexual women to be upset by sexual infidelity (54 vs. 35 %) and less likely than heterosexual women to be upset by emotional infidelity (46 vs. 65 %). This gender difference emerged across age groups, income levels, history of being cheated on, history of being unfaithful, relationship type, and length. The gender difference, however, was limited to heterosexual participants. Bisexual men and women did not differ significantly from each other in upset over sexual infidelity (30 vs. 27 %), regardless of whether they were currently dating a man (35 vs. 29 %) or woman (28 vs. 20 %). Gay men and lesbian women also did not differ (32 vs. 34 %). The findings present strong evidence that a gender difference exists in a broad sample of U.S. adults, but only among heterosexuals.     

The Effects of Sex,Sexual Orientation,and Digit Ratio (2D:4D) on Mental Rotation Performance

In spite of the reduced level of experimental control, this large scale study brought some clarity into the relation between mental rotation task (MRT) performance and a number of variables where contradictory associations had previously been reported in the literature. Clear sex differences in MRT were observed for a sample of 134,317 men and 120,783 women, with men outperforming women. There were also MRT differences as a function of sexual orientation: heterosexual men performed better than homosexual men and homosexual women performed better than heterosexual women. Although bisexual men performed better than homosexual men but less well than heterosexual men, no significant differences were observed between bisexual and homosexual women. MRT performance in both men and women peaked in the 20-30 year range, and declined significantly and markedly thereafter. Both men and women showed a significant negative correlation between left and right digit finger ratio and MRT scores, such that individuals with smaller digit ratios (relatively longer ring finger than index finger) performed better than individuals with larger digit ratios.     

Interactions between persons at risk for AIDS and the general population in Denmark.

A nationwide study of sexual behavior was undertaken among 4,680 randomly selected Danes aged 18-59 years. The median number of sexual partners (lifetime) was highest for men aged 30-34 years (eight partners) and for women aged 25-29 years (seven partners). After adjustment for age and sex, having had greater than or equal to 5 sexual partners in the past year was strongly associated with living in larger cities, intravenous drug use, and having sex with a prostitute, a bisexual man, an intravenous drug user, or a resident of sub-Saharan Africa. The frequency of ever having had anal intercourse was highest among women aged 20-34 years (range, 27%-36%) and was independently associated only with increasing number of sexual partners (lifetime). Overall, 2.7% of men reported any homosexual experience, among whom most (88%) had also had heterosexual intercourse. Prostitute contact (ever) was reported by 13% of all men and was associated with a high educational level, a history of travel, a greater number of sexual partners, and intravenous drug use. Overall, sexual contact with someone considered at high risk of human immunodeficiency virus (HIV) infection (a homosexual/bisexual man, intravenous drug user, prostitute, or sub-Saharan African resident) was reported by 15.9% of men and 4.8% of women. Among active blood donors (past year), 12.5% of men and 4.0% of women had engaged in potentially risky behavior. HIV testing was deliberately sought more often by respondents exposed to someone at increased risk of HIV infection (10.6%) than by those unexposed (6.5%, p less than 0.01). Exposure to persons at risk of HIV infection is considerable in Denmark. The majority of persons who have had potential exposure to HIV have not yet been tested for HIV.     

Suicidality and Sexual Orientation: Differences Between Men and Women in a General Population-Based Sample From The Netherlands

Homosexuality has been shown to be associated with suicidality and mental disorders. It is unclear whether homosexuality is related to suicidality, independently of mental disorders. This study assessed differences in lifetime symptoms of suicidality (death ideation, death wishes, suicide contemplation, and deliberate self-harm) between homosexual and heterosexual men and women, controlling for lifetime psychiatric morbidity. Interaction effects of age and the role of perceived discrimination were also examined. Data were collected on a representative sample of the Dutch population aged 18–64 years. Classification as heterosexual or homosexual was based upon reported sexual behavior in the preceding year. Of those sexually active, 2.8% of 2,878 men and 1.4% of 3,120 women had had same-sex partners. Homosexual men differed from their heterosexual counterparts on all four suicide symptoms (OR ranging from 2.58 to 10.23, with higher ORs for more severe symptoms), and on the sum total of the four symptoms; homosexual women only differed from heterosexual women on suicide contemplation (OR=2.12). Controlling for psychiatric morbidity decreased the ORs, but among men all associations were still significant; the significance for suicide contemplation among women disappeared. Younger homosexuals were not at lower risk for suicidality than older homosexuals in comparison with their heterosexual counterparts. Among homosexual men, perceived discrimination was associated with suicidality. This study suggests that even in a country with a comparatively tolerant climate regarding homosexuality, homosexual men were at much higher risk for suicidality than heterosexual men. This relationship could not only be attributed to their higher psychiatric morbidity. In women, there was no such clear relationship.     

Vulnerability, unsafe sex and non-adherence to HAART: evidence from a large sample of French HIV/AIDS outpatients

Current socio-behavioural research in HIV-infected people has tried to identify patients with "high-risk" profiles, i.e. who simultaneously exhibit non-adherence to highly active anti-retroviral therapy (HAART) and unsafe sex with serodiscordant partners. We challenged this approach by investigating the correlates of both behaviours, for homosexual men, heterosexual men and heterosexual women separately, among a representative sample of 4963 HIV-infected people in France. Variables introduced in the analysis dealt with patients' background and daily life, with a focus on situations of economic, social and personal vulnerability. Overall, 2932 patients agreed to participate, and 1809 were both receiving HAART and sexually active. Among heterosexual women, non-adherence and unsafe sex appeared as joint outcomes of similar situations of vulnerability. Among heterosexual men, these behaviours were weakly correlated and shared some predictors related to situations of vulnerability. Among homosexual men, non-adherence and unsafe sex were not correlated and had distinct determinants. Situations of vulnerability, the context and the motives of unsafe sex, as well as factors associated with non-adherence and unsafe sex varied greatly with gender and sexual preference. Theoretical models used for designing behavioural interventions should take into account this diversity.