Sexual Hookups Among College Students: Sex Differences in Emotional Reactions John Marshall Townsend & Timothy H. Wasserman Archives of Sexual Behavior The Official Publication of the International Academy of Sex Research ISSN 0004-0002 Volume 40 Number 6 Arch Sex Behav (2011) 40:1173-1181 DOI 10.1007/s10508-011-9841-2 1 23 Your article is protected by copyright and all rights are held exclusively by Springer Science+Business Media, LLC. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author’s version for posting to your own website or your institution’s repository. You may further deposit the accepted author’s version on a funder’s repository at a funder’s request, provided it is not made publicly available until 12 months after publication. 1 23 Author's personal copy Arch Sex Behav (2011) 40:1173–1181 DOI 10.1007/s10508-011-9841-2 ORIGINAL PAPER Sexual Hookups Among College Students: Sex Differences in Emotional Reactions John Marshall Townsend • Timothy H. Wasserman Published online: 6 October 2011 Springer Science+Business Media, LLC 2011 Abstract The purpose of the study was to test four predictions derivedfrom evolutionary (sexual strategies)theory.Thecentral hypothesis wasthat menand womenpossessdifferent emotional mechanisms that motivate and evaluate sexual activities. Consequently, even when women express indifference to emotional involvement and commitment and voluntarily engage in casual sexual relations, their goals, their feelings about the experience, andtheassociationsbetweentheirsexual behaviorandprospects for long-term investment differ significantly from those of men. Women’s sexual behavior is associated with their perception of investment potential: long-term, short-term, and partners’ abilityandwillingnesstoinvest.Formen,theseassociationsareweaker or inversed. Regression analyses of survey data from 333 male and 363 female college students revealed the following: Greater permissivenessofsexualattitudeswaspositivelyassociatedwithnumber of sex partners; this association was not moderated by sex of subject (Prediction 1); even when women deliberately engaged in casual sexual relations, thoughts that expressed worry and vulnerability crossed their minds; for females, greater number of partnerswasassociatedwithincreasedworry-vulnerabilitywhereasfor males the trend was the opposite (Prediction 2); with increasing numbers of sex partners, marital thoughts decreased; this finding was not moderated by sex of subject; this finding did not support Prediction3;forbothmalesandfemales,greaternumberofpartners was relatedtolargernumbers ofone-night stands,partnersforeseen in the next 5 years, and deliberately casual sexual relations. This J. M. Townsend (&) Department of Anthropology, Syracuse University, Syracuse, NY 13244-1090, USA e-mail: jmtsu44@aol.com T. H. Wasserman Office of Institutional Research and Assessment, Syracuse University, Syracuse, NY, USA trend was significantly stronger for males than for females (Prediction 4). Keywords Emotions Sexuality Evolution Sex differences Introduction Researchers have consistently identified the following sex differences in sexuality and partner selection. Male sexuality is more focused on the genitalia and orgasm, and men are more willing to engage in sexual relations in the absence of emotional involvement and marital potential and more likely to seek sexual relations with a variety of partners (Buss, 1995; Kinsey, Pomeroy, Martin, & Gebhard, 1953; Schmitt, 2005). Men place more emphasis than women on physical attractiveness in choosing partnersforsex ormarriage,andwomenplacemoreemphasison partners’ socioeconomic status (SES) (Buss, 1989a). These sex differences appear to be universal (Schmitt, 2005). Schmitt (2005) used the Sociosexual Orientation Inventory (SOI) to study sexual attitudes and behavior in 48 nations. The results indicated that, in harsher environments, where women are more economically dependent on men, women move toward monogamy whereas men remain relatively promiscuous. Sex differences in sexual attitudes and behavior are, therefore, larger in environments that are harsh and lack gender equality. In less demanding environments, where women enjoy greater economic independence, sex differencesin sexual attitudes and behavior are smaller. .As predicted by evolutionary theory, although sex differences are attenuated in modern Western nations, they remain consistently significant (Buss, 1995; Schmitt, 2005). Consistent with Schmitt’s (2005) findings, recent research indicates that a growing number of young people in North America engage in casual sexual encounters known as hookups 123 Author's personal copy 1174 (Grello, Welsh, & Harper, 2006; Owen, Rhoades, Stanley, & Fincham, 2010; Paul & Hayes, 2002). Although the reported incidenceofhook-upsvaries, studies consistently report frequencies of 40–80% (Garcia & Reiber, 2008; Grello, Welsh, Harper, & Dixon, 2003; Owen & Fincham, 2011; Paul, McManus, & Hayes, 2000). Sexual Strategies and Emotions Evolutionary psychologists propose that the sexes’ different reproductive risks, constraints, and opportunities caused them to evolve differential strategies to solve reproductive problems (Buss & Schmitt, 1993). Emotions play a crucial role in human sexual strategies (Buss, 1989b; Symons, 1979). Over the past several million years, human females evolved emotional-perceptual mechanisms that cause them to be attracted by partners’ ability and willingness to invest, evaluate the quality of investment, and detect and counteract shirking and false advertising. Human male mechanisms include the capacity to dissociate sexual pleasure from investment and a desire for a variety of sex partners who exhibit signs of fertility (Bailey, Gaulin, Agyei, & Gladue, 1994). By their very nature, male and female strategies often conflict and interfere with each other; these conflicts represent strategic interference. Over eons men and women evolved emotional-motivational mechanisms that alert them to strategic interference and allow them to alter their own behavior and influence the behavior of the opposite sex to eliminate or reduce the interference (Buss, 1989b, 1994a). The concepts of‘‘sexual strategies’’ and ‘‘solutions to adaptive problems’’ do not imply that the strategies or problems they solve are consciously articulated. Rather, they operate as desires, attractions, and gut-level emotionsthatdirectandmotivateaction(Buss&Schmitt,1993). In casual sexual encounters, males and females overlap substantially in their stated motivations, sexual attitudes, and partner-selection criteria (Garcia & Reiber, 2008; Kenrick, Groth, Trost, & Sadalla, 1993; Owen, Fincham, & Moore, 2011). Nevertheless,females’greaterconcernregardingthequalityand duration of investment emerges despite their endorsement of permissive sexual attitudes and behavior. Garcia and Reiber (2008) found an equal percentage of males and females mentioned sexual gratification and the possibility of starting romanticrelationshipsasreasonsforhookingup. However,maleswere more likely to have sex with mere acquaintances and strangers and hope for more hook-ups in the future; females were more likely to hook-up with known persons and romantic partners and hope for traditional romantic relationships. Similarly, in Owen and Fincham (2011), females were more likely than males to hope that their hookups would become committed relationships. Evolutionary psychologists argue that women’s thoughts and fantasies about romance, marriage, and children indicate concern about and desire for long-term male investment (Buss & Schmitt, 1993; Ellis & Symons, 1990). Townsend (1995, 1998) reported that even in initial sexual encounters females had more 123 Arch Sex Behav (2011) 40:1173–1181 romantic thoughts than males did. For females, the reported incidence of these thoughts did not decline with greater numbers of sex partners, whereas for males it did decline. Emotional Reactions to Hookups With few exceptions, research indicates that females’ reactions to sexual hookups tend to be negative, whereas males’ reactions tend to be positive. Simpson (1987) found that sexually permissive women experienced more intense and prolonged emotional distress following dissolution than less permissive women and more permissive and less permissive men. Townsend (1987, 1995,1998)reportedthatconcernregardingqualityandduration of investment emerged even in women who expressed complete acceptance of casual sex. Wondering after an encounter whether a man would call, whether he cared at all or just wanted sex, whether she would ever see him again, and if she did, whether he would even remember her, all signaled concern about investment. Consistent with this characterization, Paul and Hayes (2002) found that, for women,‘‘not knowing their partner and the lack of further contact with the partner seemed to compound their regret and anger at themselves’’(p. 655). Common negative experiences for males were the partner was insufficiently attractive and/or was too promiscuous; common themes for females were shame, regret, self-blame, and felt-pressure to perform unwanted sex acts (Paul & Hayes, 2002). Similarly, Glenn and Marquardt (2001) found that after hooking up, many women felt hurt and confused about their future relations with their partners. In Grello et al. (2006), men with more casual partners had fewer depressive symptoms, whereas women with more casual partners had more depressive symptoms. Fielder and Carey (2010) also found that penetrative hookups correlated positively with psychological distress for females, but inversely for males. Owen et al. (2010) and Owen and Fincham (2011) reported that males had more positive reactions to hookups than did females (although females’ reactions were generally positive). In a onesemester prospective study, Owen et al. (2011) found that penetrative hookups were associated with less distress and loneliness for participants who began the semester with greater distress and loneliness. Participants who began the semester with less distress and loneliness reported an increase in these symptoms at the end of the semester if they engaged in penetrative hookups. Owen et al. concluded that for some young people hookups can provide a positive experience and actually improve psychological well-being—at least in the short term. Consistent with Owen et al. (2011), Townsend (1987, 1995, 1998) found that women did not necessarily react to casual sexual relations negatively, and some women found them enjoyable. As long as a man appeared willing to invest at the level the woman felt appropriate at the moment, she felt in control, and feelings of worry, vulnerability and exploitation did not emerge. However, females’ concern regarding investment did not decline with greater numbers of partners whereas men’s concern did Author's personal copy Arch Sex Behav (2011) 40:1173–1181 decline, and even very permissive women experienced disturbing emotional reactions when they attempted to maintain sexual relationships that involved insufficient investment (Townsend 1987, 1995, 1998). Qualitative studies of women’s evaluations of hookups are consistent with this interpretation (Glenn & Marquardt, 2001; Paul & Hayes, 2002). Gangestad and Simpson (2000) argued that female sexuality facultatively shifts in demanding environments, and women become more restricted. Virtually all men desire a variety of sex partners (Bailey et al., 1994; Kinsey et al., 1953), but when most women require investment with sex, only the most attractive heterosexual men (socially dominant,geneticallyfit)canengage in low-investment copulations (Gangestad & Simpson, 2000; Townsend, 1993, 1995). Schmitt’s 48-nation study (2005) supportedthisview,andsexualhookupsamongcollegestudentsprovide ample support as well. Given the permissiveness of many female college students, attractive male students enjoy unprecedented opportunity to fulfill their desire for a variety of physically attractive sexual partners (Garcia & Reiber, 2008; Grello et al., 2006; Townsend, 1993, 1998). The Current Study The goals of the current study were to discover how many deliberate casual partners subjects had had, and analyze intercorrelations among subjects’ number of sex partners, sexual attitudes, and how they felt about their casual sexual relations. We hypothesized the following: the fundamental sexual desires that motivate action and the emotional reactions that evaluate these actions differ in men and women. These desires and emotions exist in a feedback system so that even if men and women express identical sexual attitudes and goals, they nevertheless are motivated to engage in different types of activities, and their emotional react ions to the same activities (e.g., casual sexual relations) differ significantly. Predictions On measures such as the SOI, permissive sexual attitudes are reflected incorrespondinglypermissive sexual behaviorforboth males and females (Paul et al., 2000; Schmitt, 2005; Simpson & Gangestad, 1991). Prediction 1: For both sexes, permissiveness of sexual attitudeswillbepositivelyassociatedwithgreaternumbersofsex partners. In contrast to conventional measures of sexual attitudes, the thoughts and feelings that concern investment, and the emotions that occur in response to actual sexual relations are proximate mechanisms that alert women to strategic interference and guide them toward relationships that offer higher levels of investment. Number of sex partners should therefore associate differentially with males’ and females’ feelings concerning investment. 1175 Prediction 2: With increasing numbers of sex partners, females will experience more vulnerability and worry regarding investment whereas males will experience less worryvulnerability; the gender 9 total number of sex partners interaction term will be significant. Females typically think about romance, marriage, and children more than do males; these thoughts indicate concern about and desire for long-termmale investment (Ellis & Symons, 1990; Townsend, 1998). In shortterm relationships, concern about long-term investment is reduced for both sexes, but this reduction is stronger for males than for females (Buss & Schmitt, 1993). Prediction 3: With increasing numbers of partners, the incidence of marital thoughts will decline for males more than for females; the gender 9 total number of sex partners interaction for marital thoughts will be significant. Compared to women, men report larger numbers of one-night stands, partners in the last year, and deliberately casual partners (Gangestad & Simpson, 2000; Schmitt, 2005). Prediction 4: If the fundamental sexual desires that motivate action, and the emotional reactions that evaluate these actions differ as proposed, it is predicted that with increasing numbers of sex partners, those sexual behaviors that involve minimal investment will increase more for males than for females; consequently, the gender 9 total number of partners interaction will be significant for casual sexual behaviors. Method Participants The participants were 335 male and 365 female students from an introductory psychology course at a private, northeastern university in the U.S. Participants received credit toward the research participation requirement of the class. All subjects in both samples were unmarried and between the ages of 18 and 23 years. University policy dictates that sign-up sheets for experiments be accompanied by a brief description of the task. Participants thereforereadwhentheysignedupthattheinvestigatorswere‘‘interested in heterosexual dating and sexual experience.’’To our knowledge, no participants declined to participate after they signed the consent form. Procedure Participants completed the surveys in same-sex groups of 10–20 under the supervision of like-sex, graduate research assistants. Participants read and signed a standard consent form that was approved by the University’s Institutional Review Board. After participants completed their consent forms, they read the following instructions: ‘‘You are asked to complete a brief questionnaire concerning your choice of partners for different types 123 Author's personal copy 1176 Arch Sex Behav (2011) 40:1173–1181 of relationships. There will also be some background information requested of you. Please answer all questions as honestly as you can. If you feel a question is not applicable, you may leave it blank. Remember, all your responses will be kept completely confidential. There is no way we can identify you with your responses, and we truly have no interest in doing so. You are now ready to begin. Please turn to the next page. If at any time you have a question, raise your hand and we will assist you.’’ for analysis (Cronbach’s alpha = .77):‘‘Even when I’ve first met a guy/girl, if I have sex with him/her, afterwards, thoughts cross my mind like: ‘I wonder what it would be like being married to him/her? What would our wedding be like? Where would we go on our honeymoon? What would our kids look like?’‘‘ The marital thoughts and worry-vulnerability items were followed by agree-disagree scales, where 1 = strongly disagree, 5 = undecided, and 9 = strongly agree. Measures Casual Sexual Behavior Sexual Attitudes We used two of the SOI behavior items (partners in last year and one-night stands). We did not include‘‘partners foreseen in the next 5 years’’because it is speculative and does not refer to actual behavior; the SOI fantasy item was omitted for similar reasons. An additional question was aggregated with the two SOI behavior questions (Cronbach’s alpha = .83):‘‘Have you ever had sex with someone, and you knew before you had sex that you did not want to get emotionally involved with this person; with how many partners have you done this?’’This item was designed to identify sexual relations that were deliberately casual, i.e., relations that involved little investment of time and emotion and were not supposed to lead to a more serious relationship (Townsend, Kline, & Wasserman, 1995). The SOI normally consists of seven questions: number of sex partners in the previous year; number of one-night stands; number of sex partners foreseen in the next 5 years; frequency of sexual fantasies about people other than the current dating partner; and three attitudinal questions:‘‘Sex without love is ok’’;‘‘I can imagine myself being comfortable and enjoying ‘casual’ sex with different partners’’;‘‘I would have to be closely attached to someone (both emotionally and psychologically) before I could feel comfortable and fully enjoy having sex with her/him.’’The SOI correlates with numerous measures of sexuality and personality (Gangestad & Simpson, 2000). In the current questionnaire,‘‘havingsex’’and‘‘sexpartner’’weredefinedas:‘‘sexualintercourse, including oral sex.’’ To measure sexual attitudes, we adopted the three attitude questions from the SOI. A fourth item stated:‘‘I feel I should be emotionally involvedwith a man/womanbefore havingsex with him/her.’’ This item’s correlations with other measures of attitudes and behavior were similar to those of the SOI attitude items (Townsend, 1995); consequently, this item was aggregated with the three SOI attitude questions (Cronbach’s alpha = .86). The four attitude items were answered on Likert-type scales, where 1 = strongly disagree, 5 = undecided, and 9 = strongly agree. Worry-Vulnerability The following question assessed feelings of concern and vulnerability that occurred in response to repeated sexual relations with a casual partner: ‘‘Even if I don’t think I want to be emotionally involved with a person, if I have sex with him/her a few times, I begin to feel vulnerableandwould at least liketoknow he/shecares about me.’’This item focused on two aspects of the hypothesized sexual emotions: the involuntary nature of these feelings (i.e., they occur regardless of whether the participant wishes to become emotionally involved); that repeated sexual relations with someone are more likely to elicit these feelings than a single encounter Marital Thoughts To assess marital thoughts, the following questions were adopted from previous research (Townsend, 1995) and aggregated 123 Results To test for gender differences, t-tests were performed on the items and aggregates; results, along with the effect sizes, appear in Table 1. To control for gender differences in mean responses and numbers of sex partners, participants’ responses were subjected to regression analyses, with participant’s gender and total number of sex partners as independent variables, and responses to the items and aggregates in Table 1 as dependent variables (participant’sgenderwasdummycoded: 0 = male; 1 = female). Regression analyses appear in Table 2. Sexual Attitudes Compared to women, men tended to report more permissive sexual attitudes. For all attitude questions, these gender differences were highly significant; d-values were large and ranged from .85 to 1.19 (see Table 1). Regression analysis of the sexual attitudes scale showed that, controlling for number of partners, males had more permissive attitudes than females (see Table 2). For both sexes, number of partners was positively associated with increasingly permissive attitudes; the gender 9 number of partners interaction was non-significant. Hence, the gender difference in attitudes was not moderated by number of partners. Controlling for number of partners, males endorsed casual sex more strongly than females and this gender difference remained constant. These findings supported Prediction 1. Author's personal copy Arch Sex Behav (2011) 40:1173–1181 1177 Table 1 Mean sexual attitudes, worry-vulnerability, marital thoughts, and casual sexual behavior by gender and number of sex partners Men Women M SD M t SD d-between sex Sexual attitudes 1. Sex without love is ok 5.89 2.36 3.83 2.46 11.40** 0.85 2. Can imagine I enjoy ‘‘casual’’ sex 5.68 2.52 3.02 2.41 14.38** 1.04 3. Need attachment to enjoy sex 4.94 2.57 7.18 2.41 -11.97** 0.90 4. Need emotional involvement before sex 5.12 2.52 7.30 2.13 -12.41** 0.94 21.50 8.13 12.37 7.28 15.94** 1.19 5.57 2.28 6.96 2.22 5.42** 0.61 3.80 2.45 4.65 2.89 2.85* 0.32 Sexual attitudes aggregate Worry-vulnerability 5. Worry/feel vulnerable if I have repeated casual sex with same partner Marital thoughts 6. Have romantic/marital thoughts after initial casual sexual encounters Casual sexual behavior 7. Number of sex partners in the last year 2.44 1.11 2.23 0.92 2.69* 0.21 8. Number of one-night stands 2.17 1.25 1.73 0.86 5.39** 0.41 9. Intentional sexual relations without emotional involvement (number of partners) 2.21 1.31 1.68 0.97 5.88** 0.46 Casual sexual behavior aggregate 6.82 3.26 5.64 2.38 5.85** 0.42 Note: Males, n = 333, females, n = 363. For Questions 1–6, absolute range, 1–9. For Questions 5 and 6, participants who did not engage in these activities were omitted from analysis (n = 186 males and 134 females). Items 3 and 4 were reverse-scored for creation of the Sexual attitudes aggregate. d-between sex describes the effect size of gender differences between mean responses; effect sizes of .2 are considered small, .5 are medium, and .8 are large (Cohen, 1992) * p\.05, ** p\.0001 Worry-Vulnerability for females the trend was the opposite. These findings supported Prediction 2. Women reported a higher mean level of worry-vulnerability than men; the effect size was .61, which is considered a mediumlevel effect (Table 1). With number of partners controlled through regression, this gender difference no longer reached significance (Table 2). Greater number of partners was associated with decreased worry-vulnerability; however, this effect was qualified by a significant gender 9 number of partners interaction. For females, greater number of partners was associated with increased worry-vulnerability. Taken together, the main effect for number of partners and the gender 9 number of partners interaction showed that for males, greater number of partners was associated with reduced worry-vulnerability whereas Marital Thoughts Relative to males, females reported a greater tendency to experience marital thoughts; effect size was .32, a small effect (Table 1). However, with number of partners controlled via regression analysis, this gender difference was not significant. As number of partners increased, marital thoughts decreased. This main effect for number of partners was not qualified by gender, i.e., the gender 9 number of partners interaction was not significant (Table 2). These findings did not support Prediction 3. Table 2 Standardized regression estimates of attitudes, worry-vulnerability, marital thoughts, and casual sexual behavior, by gender and number of sex partners Dependent variables Independent variables Gender Sexual attitudes -0.494*** Number of partners 0.337*** Gender 9 Number of partners Model F 0.053 128.80*** Worry-vulnerability 0.064 -0.130* 0.259* 11.73*** Marital thoughts Casual sexual behavior 0.026 0.030 -0.146* 0.93*** 0.156 -0.193*** 4.66** 661.60*** Males (coded‘‘0’’), n = 333; females (coded‘‘1’’), n = 363. For Worry-vulnerability and Marital Thoughts, only subjects who reported that they had engaged in those activities were included in analysis (n = 186 males and 134 females) * p\.05, ** p\.01, *** p\.0001 123 Author's personal copy 1178 Casual Sexual Behavior Compared to females, males reported more one-night stands, partners in the last year, and intentional sex without emotional involvement; effect sizes ranged from .21 to .46, which are small effects (Table 1). When number of partners was controlled in the regression analysis, however, the gender difference for casual sexual behavior failed to reach significance (Table 2). Predictably, total number of sex partners was highly associated with the casual sexual behavior items, but this main effect was moderated by a gender 9 total number of partners interaction. Although both sexes reported increased casual sexual behavior with increased number of partners, compared to males, the increase for females was significantly smaller (though still in the positive direction); hence, the gender 9 total number of partners interaction was significant for casual sexual behavior. These findings supported Prediction 4. Discussion The goals of the current study were to discover how many deliberate casual partners subjects had had, and analyze intercorrelations among subjects’ number of sex partners, sexual attitudes, and how they felt about theircasual sexual relations. Compared to females, males tended to have more permissive sexual attitudes. This gender difference was not moderated by number of partners (Prediction 1). Viewed alternatively, compared to males, females acquired an equal number of sex partners despite their less permissive attitudes. Arguably, this occurred because males tend to be less selective than females in choosing partners and generally more willing to engage in low-investment copulation (Baumeister, Catanese & Vohs, 2001; Townsend, 1993). Thisgenderdifferenceremainedconstantdespiteincreasingnumbers of partners. Compared to men, women were more likely to agree that they experiencedworry-vulnerabilityevenwhentheyhadnotwanted emotional involvement. In contrast to our measures of sexual attitudes, the gender 9 number of partners interaction was significant for worry-vulnerability. Taken together, the main effect for number of partners and the gender 9 number of partners interaction showed that for males, greater number of partners was associated with reduced worry-vulnerability, whereas for females the trend was the opposite (Prediction 2). Prior studies have reported that penetrative hookups correlated positively with females’ depressive symptoms and other indices of psychological distress, whereas for males this association was reversed (Fielder & Carey, 2010; Glenn & Marquardt, 2001; Grello et al., 2006; Simpson, 1987). Our measures could not determine whether worry-vulnerability was associated with depressive symptoms or other types of psychological distress, nor whether women’s emotional reactions contributed to their lesser interest and indulgence in casual relations. Nevertheless, the current 123 Arch Sex Behav (2011) 40:1173–1181 findings were certainly consistent with these prior studies and with this proposition. With increasing numbers of partners, marital thoughts declined for both sexes. The gender 9 number of partners interaction was non-significant (Prediction 3), whereas in a prior study it was significant: with increasing number of partners, the reduction in marital thoughts was greater for males than for females (Townsend, 1995). Arguably, contemporary females are less likely than thosein1995 tobelievethat relationshipsbegunincollegewill end in marriage, and more likely to postpone marriage (Garcia & Reiber, 2008). The current female tendency to delay marriage may account for the discrepancy between the current and previous findings (Townsend, 1995). Contemporary females who engage in hookups may express desire for romantic or committed relationships rather than for marriage (Garcia & Reiber, 2008; Owen & Fincham, 2011). In future research the marital-thoughts question will be reformulated to assess desire for relationships. Compared to women, men tended to have more sex partners last year, one-night stands, and deliberate casual partners (casual sexual behavior). With total number of partners controlled through regression, the main effect for gender was non-significant. However, this main effect was moderated by a significant gender by number of partners interaction. Both sexes reported increased casual sexual behavior with increased number of partners, but this increase was significantly greater for males than for females (Prediction 4). This finding is consistent with the proposition that males and females differ in their sexual motivations: compared to females, males are more strongly motivated to copulate with a variety of partners who exhibit the signs of youth and fertility (Baumeister et al., 2001; Regan & Atkins, 2006; Symons, 1979). Hence, when opportunity allows, the most attractive males engage in low-investment copulation with multiple partners, and their number of casual partners increasingly diverges from that of even the most permissive females because the sexes’ underlying motivations differ. Furthermore, our male participants’ responses were consistent with previous reports of environmentally-contingent shifts in male preferences, emotions, and behavior (Buss, 1994b; Landolt, Lalumiere, & Quinsey, 1995; Penke & Denissen, 2008; Waller, 1994). Taken together, the current findings and these previous studies supported our general proposition: although the sexes overlap considerably in their sexual attitudes and behavior, their underlying motivations differed and they, therefore, differentially utilized sexual opportunities. Our data cannot determine whether women’s emotional reactions contribute to their lesser interest and indulgence in casual relations, nor can they determine whether worry-vulnerability is associated with depressive symptoms and other measures ofpsychologicaldistress.Nevertheless,itisplausiblethatthistype of feedback occurs, and the sex differences in worry-vulnerability that we recorded are part of this sexually dimorphic feedback. Even in women with very permissive attitudes, concern about the reliability and adequacy of investment (as expressed in worry, Author's personal copy Arch Sex Behav (2011) 40:1173–1181 vulnerability, regret, and shame) serves to evaluate investment and guard against strategic interference (i.e., sexual relations with partners who are unwilling or unable to invest sufficiently). Further participation in casual sexual activities increases females’ worryandnegativeemotions;thesenegativefeelingsarereflected in measures of psychological distress. If this interpretation is correct, men and women tend to receive differential feedback when they engage in casual sexual relations. For women, their feelings and memories can be very negative; for men, they are more often positive, and they stimulate men to attempt to repeat the experience (Fielder & Carey, 2010; Kinsey et al., 1953; Townsend, 1987, 1995). Owen et al. (2011) concluded that for some young people hookups can provide a positive experience—at least in the short term. Consistent with this interpretation, Townsend (1987, 1995, 1998) found that permissive women could sporadically engage in casual sexual encounters with few negative consequences. Many contemporary women experiment with casual relations, but most eventually tire of them and gravitate toward relationshipsthatoffersuperiorlevelsofinvestment(Townsend, 1998). Furthermore, even extremely permissive women experience disturbing emotional reactions when they attempt to maintain sexual relationships that involve insufficient investment(Townsend,1987,1995,1998).Thesefindingssuggest that control over level of investment, more than traditional morality, may determine permissive women’s emotional reactions to casual sex. Women’s qualitative evaluations of their hookups areconsistent withthisinterpretation:permissivewomendidnot appear to reject casual sex per se; rather, they felt upset when theirpartnersshowedinsufficientinterestinthemandtheirneeds (Glenn & Marquardt, 2001; Paul & Hayes, 2002). Some factor causes even permissive women to desire relationships that offer quality investment, and eventually to be disturbed by relationships that involve inadequate investment. We propose that the feelings expressed in worry-vulnerability are part of the emotional feedback that limits women’s experiments with casual relations and guides them toward higher-investment relationships. The current findings were thus consistent with our general hypothesis: Even when women express indifference to emotional involvement and commitment and voluntarily engage in casual sexual relations, their hopes and feelings about the experience differ significantly from those of men. Women’s sexual behavior and their emotional reactions to this behavior are associated with their perception of investment. For men these associations are weaker or reversed. Limitations The worry-vulnerability item stated,‘‘…if I have sex with him/ her a few times, I begin to feel vulnerable and would at least like to know he/she cares about me’’(see Appendix). This formulation implies that participants experience these thoughts every timetheyengageinthisactivity.Hence,apersonwhoengagedin 1179 thisactivitywithmanypartnerswouldexperiencethesethoughts more frequently than someone who tried it with fewer partners. Yet, both of these individuals could mark the same point on the agree-disagree answer scale and thus appear to experience these thoughts with the same frequency. The way the item was worded it was impossible to determine the actual frequency of worryvulnerability thoughts. We plan to address this issue in future research. Even with this limitation, however, the gender 9 number of partners interaction was significant: for males, greater number of partners was associated with reduced worry-vulnerability whereas for females the trend was the opposite. Because our samples were cross-sectional and analysis correlational, we cannot determine causal relationships among the study variables. Nevertheless, men’s greater willingness to have sex with attractive partners suggests that most men have sufficient desire to lead to multiple casual encounters if opportunity allows, and the emotional feedback they receive motivates them to repeat the experience (Baumeister et al., 2001; Gangestad & Simpson, 2000; Regan & Atkins, 2006; Schmitt, 2005). We propose, therefore, that the attitudes, thoughts, and feelings of men with more experience in casual relations diverge from those of less experienced men as the former gain familiarity, confidence, and experience. In comparison, women derive a contrary lesson from casual sexual relations; such relations can be fun initially, but most women eventually experience them as unfulfilling (if not degrading) and consequently seek higherinvestment relationships. Research among college students and young professionals supports this characterization of gender differences (Todd, Penke, Fasolo, & Lenton, 2007; Townsend, 1987; Townsend & Roberts, 1993; Townsend & Wasserman, 1998). Implications Conventional measures of sexual attitudes can be poor predictors of behavior (Penke & Asendorpf, 2008), and even more inadequate in predicting emotional reactions (Townsend, 1995, 2005). Open-ended questions allow participants to express their feelings in their own words and thus may provide a better window into actual emotional reactions (Glenn & Marquardt, 2001; Paul&Hayes,2002;Townsendetal.,1995).Similarly,theuseof clinical instruments that are ostensibly independent of questions regarding sexual attitudes and behavior may reduce demand characteristics and thus reveal otherwise hidden associations between sexual behavior and emotional reactions (Fielder & Carey, 2010; Grello et al., 2006). Motivations for sexual encounters present a similar problem. Townsend (1993, 1998) found that college men’s financial resources, athletic ability, and expected incomes were positively associated with number of sex partners. Simply asking women, however, whether male status influences their partner selection often elicits denial because this motive is unconscious and/or socially unacceptable (Townsend, 1998). In contrast, more 123 Author's personal copy 1180 Arch Sex Behav (2011) 40:1173–1181 oblique methods can reveal the effects of male status (van Straaten, Engels, Finkenauer, & Holland, 2008). Similarly, appropriate experimental designs as well as forced-choice and open-ended questions have revealed the powerful, yet sometimes obscure effects of male status and resources on females’ choice of partners—both for short-term and long-term relationships (Buss & Schmitt, 1993; Todd et al., 2007; Townsend, 1989, 2005; Townsend & Levy, 1990; Townsend & Roberts, 1993; Townsend & Wasserman, 1998). Paul and Hayes (2002) found that students tended to idealize hook-ups and ignore their negative aspects: ‘‘Especially worrisome was females’ lack of communication about unwanted or forced sexual involvement’’ (p. 657). Other researchers have echoed this concern (Lambert, Kahn, & Apple, 2003). This dearth of communication reifies the popular, positive image of hook-ups, and produces a vicious cycle of more hook-ups, regret, and self-blame in women (Paul & Hayes, 2002). The current findings and literature reviewed suggest that many contemporary women approve, in principle, of casual sexual relations and believe that they will enjoy them. Many, however, will eventually discover that they do not like casual sex, or at least not when they lack control of male investment, and this discovery can be painful. Increasing freedom and opportunities does cause men and women to overlap in some aspects of their sexual attitudes and behavior, but it also allows more men, particularly those with high status, to attempt low-investment copulations, and more women to feel exploited when they succeed. The doyenne of feminist sociology, Bernard (1972), predicted that the more freedom men and women enjoy, ‘‘the more fundamental and ineradicable differences will show up’’ (p. 256). The evidence reviewed here was consistent with her prediction. Appendix Question Content Sexual Attitudes 1. 2. 3. 4. Sex without love is ok I can imagine myself being comfortable and enjoying ‘‘casual’’ sex with different partners. I would have to be closely attached to someone (both emotionally and psychologically) before I could feel comfortable and fully enjoy having sex with him/her. I feel I should be emotionally involved with a man/woman before having sex with him/her Worry-Vulnerability 5. 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