Pairing off
Genetic and educational assortative mating among US adults
Benjamin Domingue et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
Understanding the social and biological mechanisms that lead to homogamy (similar individuals marrying one another) has been a long-standing issue across many fields of scientific inquiry. Using a nationally representative sample of non-Hispanic white US adults from the Health and Retirement Study and information from 1.7 million single-nucleotide polymorphisms, we compare genetic similarity among married couples to noncoupled pairs in the population. We provide evidence for genetic assortative mating in this population but the strength of this association is substantially smaller than the strength of educational assortative mating in the same sample. Furthermore, genetic similarity explains at most 10% of the assortative mating by education levels. Results are replicated using comparable data from the Framingham Heart Study.
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Martin Monto & Anna Carey
Journal of Sex Research, forthcoming
Abstract:
Popular media have described intimate relationships among contemporary college students as dominated by a pervasive sexual “hookup culture,” implying that students are involved in frequent sexual encounters pursued by both participants without the expectation of a continuing relationship. The hookup culture has been described as “a nationwide phenomenon that has largely replaced traditional dating on college campuses” (Bogle, 2008, p. 5). We tested whether these claims are supported among young adults (18–25) who had completed at least one year of college. Contrasting 1988–1996 waves of the General Social Survey with 2004–2012 waves, we found respondents from the current era did not report more sexual partners since age 18, more frequent sex, or more partners during the past year than respondents from the earlier era. Sexually active respondents from the current era were more likely than those from the earlier era to report sex with a casual date/pickup or friend, and less likely to report sex with a spouse/regular partner. These modest changes are consistent with cultural shifts in the “scripts” and terminology surrounding sexuality. We find no evidence of substantial changes in sexual behavior that would indicate a new or pervasive pattern of non-relational sex among contemporary college students.
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Gender and Sexual Economics: Do Women View Sex as a Female Commodity?
Laurie Rudman & Janell Fetterolf
Psychological Science, forthcoming
Abstract:
In the study reported here, data from implicit and behavioral choice measures did not support sexual economics theory’s (SET’s) central tenet that women view female sexuality as a commodity. Instead, men endorsed sexual exchange more than women did, which supports the idea that SET is a vestige of patriarchy. Further, men’s sexual advice, more than women’s, enforced the sexual double standard (i.e., men encouraged men more than women to have casual sex) — a gender difference that was mediated by hostile sexism, but also by men’s greater implicit investment in sexual economics. That is, men were more likely to suppress female sexuality because they resisted female empowerment and automatically associated sex with money more than women did. It appears that women are not invested in sexual economics, but rather, men are invested in patriarchy, even when it means raising the price of sexual relations.
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Prioritization of Potential Mates’ History of Sexual Fidelity During a Conjoint Ranking Task
Justin Mogilski, Joel Wade & Lisa Welling
Personality and Social Psychology Bulletin, forthcoming
Abstract:
This series of studies is the first to use conjoint analysis to examine how individuals make trade-offs during mate selection when provided information about a partner’s history of sexual infidelity. Across three studies, participants ranked profiles of potential mates, with each profile varying across five attributes: financial stability, physical attractiveness, sexual fidelity, emotional investment, and similarity. They also rated each attribute separately for importance in an ideal mate. Overall, we found that for a long-term mate, participants prioritized a potential partner’s history of sexual fidelity over other attributes when profiles were ranked conjointly. For a short-term mate, sexual fidelity, physical attractiveness, and financial stability were equally important, and each was more important than emotional investment and similarity. These patterns contrast with participants’ self-reported importance ratings of each individual attribute. Our results are interpreted within the context of previous literature examining how making trade-offs affect mate selection.
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Gert Stulp et al.
American Journal of Human Biology, forthcoming
Objectives: Although male height is positively associated with many aspects of mate quality, average height men attain higher reproductive success in US populations. We hypothesize that this is because the advantages associated with taller stature accrue mainly from not being short, rather than from being taller than average. Lower fertility by short men may be a consequence of their and their partner's lower scores on aspects of mate quality. Taller men, although they score higher on mate quality compared to average height men, may have lower fertility because they are more likely to be paired with taller women, who are potentially less fertile.
Methods: We analyzed data from The Integrated Health Interview Series (IHIS) of the United States (N = 165,606). Segmented regression was used to examine patterns across the height continuum.
Results: On all aspects of own and partner quality, shorter men scored lower than both average height and taller men. Height more strongly predicted these aspects when moving from short to average height, than when moving from average to taller heights. Women of a given height who scored lower on mate quality also had shorter partners.
Conclusions: Shorter men faced a double disadvantage with respect to both their own mate quality and that of their spouses. Scores of taller men were only marginally higher than those of average height men, suggesting that being tall is less important than not being short. Although effect sizes were small, our results may partly explain why shorter and taller men have lower fertility than those of average stature.
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Arielle Kuperberg & Joseph Padgett
Journal of Sex Research, forthcoming
Abstract:
This study examined 13,976 dates and 12,068 hookup encounters at 22 colleges in the United States reported by students surveyed between 2005 and 2011 in the Online College Social Life Survey (OCSLS) to determine differences between dates and hookups in partner meeting context and sex during the encounter. Students most often met date and hookup partners through institutional settings or bars and parties, with approximately two-thirds of partners met in these venues. Those who had fewer potential partners on campus (women) were less likely to find partners in campus locations and less likely to find male sexual or dating partners but more likely to date women. Men and women engaging in same-sex encounters had higher rates of meeting partners through Internet sources. Hookups were associated with partners met in bars, parties, nightclubs, and college dormitories, and were twice as likely as dates to include sex. Students were more likely to go on dates with partners met on the Internet, which we theorize is a result of low levels of trust associated with that context. Patterns found are related to the association of meeting contexts with hookup scripts, risk and trust, and local partnering markets.
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Negative frequency-dependent preferences and variation in male facial hair
Zinnia Janif, Robert Brooks & Barnaby Dixson
Biology Letters, April 2014
Abstract:
Negative frequency-dependent sexual selection maintains striking polymorphisms in secondary sexual traits in several animal species. Here, we test whether frequency of beardedness modulates perceived attractiveness of men's facial hair, a secondary sexual trait subject to considerable cultural variation. We first showed participants a suite of faces, within which we manipulated the frequency of beard thicknesses and then measured preferences for four standard levels of beardedness. Women and men judged heavy stubble and full beards more attractive when presented in treatments where beards were rare than when they were common, with intermediate preferences when intermediate frequencies of beardedness were presented. Likewise, clean-shaven faces were least attractive when clean-shaven faces were most common and more attractive when rare. This pattern in preferences is consistent with negative frequency-dependent selection.
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Menstrual cycle phase alters women's sexual preferences for composers of more complex music
Benjamin Charlton
Proceedings of the Royal Society: Biological Sciences, 7 June 2014
Abstract:
Over 140 years ago Charles Darwin first argued that birdsong and human music, having no clear survival benefit, were obvious candidates for sexual selection. Whereas the first contention is now universally accepted, his theory that music is a product of sexual selection through mate choice has largely been neglected. Here, I provide the first, to my knowledge, empirical support for the sexual selection hypothesis of music evolution by showing that women have sexual preferences during peak conception times for men that are able to create more complex music. Two-alternative forced-choice experiments revealed that woman only preferred composers of more complex music as short-term sexual partners when conception risk was highest. No preferences were displayed when women chose which composer they would prefer as a long-term partner in a committed relationship, and control experiments failed to reveal an effect of conception risk on women's preferences for visual artists. These results suggest that women may acquire genetic benefits for offspring by selecting musicians able to create more complex music as sexual partners, and provide compelling support for Darwin's assertion ‘that musical notes and rhythm were first acquired by the male or female progenitors of mankind for the sake of charming the opposite sex’.
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Estimating the Sex-Specific Effects of Genes on Facial Attractiveness and Sexual Dimorphism
Dorian Mitchem et al.
Behavior Genetics, May 2014, Pages 270-281
Abstract:
Human facial attractiveness and facial sexual dimorphism (masculinity–femininity) are important facets of mate choice and are hypothesized to honestly advertise genetic quality. However, it is unclear whether genes influencing facial attractiveness and masculinity–femininity have similar, opposing, or independent effects across sex, and the heritability of these phenotypes is poorly characterized. To investigate these issues, we assessed facial attractiveness and facial masculinity–femininity in the largest genetically informative sample (n = 1,580 same- and opposite-sex twin pairs and siblings) to assess these questions to date. The heritability was ~0.50–0.70 for attractiveness and ~0.40–0.50 for facial masculinity–femininity, indicating that, despite ostensible selection on genes influencing these traits, substantial genetic variation persists in both. Importantly, we found evidence for intralocus sexual conflict, whereby alleles that increase masculinity in males have the same effect in females. Additionally, genetic influences on attractiveness were shared across the sexes, suggesting that attractive fathers tend to have attractive daughters and attractive mothers tend to have attractive sons.
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Individual differences in preferences for cues to intelligence in the face
F.R. Moore, M.J. Law Smith & D.I. Perrett
Intelligence, May–June 2014, Pages 19–25
Abstract:
We tested for individual differences in women's preferences for cues to intelligence in male faces in accordance with hormonal status (i.e. menstrual cycle phase and use of hormonal contraceptives), relationship status and context, and self-rated intelligence. There were no effects of hormonal or relationship status (Studies 1 and 2) on preferences. There was, however, a positive relationship between self-rated intelligence and preferences for cues to intelligence in the face in the context of a long-term relationship, suggesting context-specific assortment (Study 3). In Study 4, self-rated partner intelligence correlated with preferences for facial cues to intelligence. We discuss these results in the context of intelligence as a fitness indicator and suggest that future research must control for assortative mating for cognitive traits in order to better understand intelligence in mate choice.
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Jeffrey Hall, Chong Xing & Seth Brooks
Communication Research, forthcoming
Abstract:
This article reports two studies on the accuracy of flirting detection. In Study 1, 52 pairs (n = 104) of opposite-sex heterosexual strangers interacted for 10 to 12 minutes, then self-reported flirting and perceived partner flirting. The results indicated that interactions where flirting did not occur were more accurately perceived than interactions where flirting occurred. In Study 2, twenty-six 1-minute video clips drawn from Study 1 were randomly assigned to one of eight experimental conditions that varied flirting base rate and the traditional sexual script. Participant observers (n = 261) attempted to determine if flirting occurred. The results indicated that base rate affected accuracy; flirting was more accurately detected in clips where flirting did not occur than in clips where flirting occurred. Study 2 also indicated that female targets’ flirting was more accurately judged than male targets’ flirting. Findings are discussed in relation to theory and courtship context.
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Simone Kühn & Jürgen Gallinat
JAMA Psychiatry, forthcoming
Objective: To determine whether frequent pornography consumption is associated with the frontostriatal network.
Design, Setting, and Participants: Sixty-four healthy male adults with a broad range of pornography consumption at the Max Planck Institute for Human Development in Berlin, Germany, reported hours of pornography consumption per week. Pornography consumption was associated with neural structure, task-related activation, and functional resting-state connectivity.
Results: We found a significant negative association between reported pornography hours per week and gray matter volume in the right caudate (P < .001, corrected for multiple comparisons) as well as with functional activity during a sexual cue–reactivity paradigm in the left putamen (P < .001). Functional connectivity of the right caudate to the left dorsolateral prefrontal cortex was negatively associated with hours of pornography consumption.
Conclusions and Relevance: The negative association of self-reported pornography consumption with the right striatum (caudate) volume, left striatum (putamen) activation during cue reactivity, and lower functional connectivity of the right caudate to the left dorsolateral prefrontal cortex could reflect change in neural plasticity as a consequence of an intense stimulation of the reward system, together with a lower top-down modulation of prefrontal cortical areas. Alternatively, it could be a precondition that makes pornography consumption more rewarding.
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Alec Beall & Mark Schaller
Personality and Individual Differences, October 2014, Pages 112–117
Abstract:
Drawing on life-history theory, it is predicted that individuals’ attitudinal orientation toward unrestricted short-term mating behavior, as well as their ability to engage in such behavior, are inversely related to nurturant emotional responses (tenderness) to infants. To test these hypotheses, participants (N = 305) completed measures assessing individual differences in short-term mating orientation, self-perceived physical attractiveness, dispositional tendency to experience tenderness, and their affective responses to photographs of human infants. Results revealed that (when controlling for other relevant individual difference variables) men’s short-term mating orientation and self-perceived attractiveness were inversely associated with dispositional tenderness. Also, among men only, short-term mating orientation and self-perceived attractiveness predicted less intense tenderness responses to infants.
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Social dialect and men’s voice pitch influence women’s mate preferences
Jillian O’Connor et al.
Evolution and Human Behavior, forthcoming
Abstract:
Low male voice pitch may communicate potential benefits for offspring in the form of heritable health and/or dominance, whereas access to resources may be indicated by correlates of socioeconomic status, such as sociolinguistic features. Here, we examine if voice pitch and social dialect influence women’s perceptions of men’s socioeconomic status and attractiveness. In Study 1, women perceived lower pitched male voices as higher in socioeconomic status than higher pitched male voices. In Study 2, women independently perceived lower pitched voices and higher status sociolinguistic dialects as higher in socioeconomic status and attractiveness. We also found a significant interaction wherein women preferred lower pitched men’s voices more often when dialects were lower in sociolinguistic status than when they were higher in sociolinguistic status. Women also perceived lower pitched voices as higher in socioeconomic status more often when dialects were higher in sociolinguistic status than when lower in sociolinguistic status. Finally, women’s own self-rated socioeconomic status was positively related to their preferences for voices with higher status sociolinguistic dialects, but not to their preferences for voice pitch. Hence, women’s preferences for traits associated with potentially biologically heritable benefits, such as low voice pitch, are moderated by the presence of traits associated with resource accrual, such as social dialect markers. However, women’s preferences for language markers of resource accrual may be functionally independent from preferences for potential biological indicators of heritable benefits, such as voice pitch.
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Conformity to the Opinions of Other People Lasts for No More Than 3 Days
Yi Huang, Keith Kendrick & Rongjun Yu
Psychological Science, forthcoming
Abstract:
When people are faced with opinions different from their own, they often revise their own opinions to match those held by other people. This is known as the social-conformity effect. Although the immediate impact of social influence on people’s decision making is well established, it is unclear whether this reflects a transient capitulation to public opinion or a more enduring change in privately held views. In an experiment using a facial-attractiveness rating task, we asked participants to rate each face; after providing their rating, they were informed of the rating given by a peer group. They then rerated the same faces after 1, 3, or 7 days or 3 months. Results show that individuals’ initial judgments are altered by the differing opinions of other people for no more than 3 days. Our findings suggest that because the social-conformity effect lasts several days, it reflects a short-term change in privately held views rather than a transient public compliance.