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Testing the Affiliation Hypothesis of Homoerotic Motivation in Humans: The Effects of Progesterone and Priming

Abstract

The frequency of homoerotic behavior among individuals who do not identify as having an exclusively homosexual sexual orientation suggests that such behavior potentially has adaptive value. Here, we define homoerotic behavior as intimate erotic contact between members of the same sex and affiliation as the motivation to make and maintain social bonds. Among both male and female nonhuman primates, affiliation is one of the main drivers of homoerotic behavior. Correspondingly, in humans, both across cultures and across historical periods, homoerotic behavior appears to play a role in promoting social bonds. However, to date, the affiliation explanation of human homoerotic behavior has not been adequately tested experimentally. We developed a measure of homoerotic motivation with a sample of 244 men and women. Next, we found that, in women (n = 92), homoerotic motivation was positively associated with progesterone, a hormone that has been shown to promote affiliative bonding. Lastly, we explored the effects of affiliative contexts on homoerotic motivation in men (n = 59), finding that men in an affiliative priming condition were more likely to endorse engaging in homoerotic behavior compared to those primed with neutral or sexual concepts, and this effect was more pronounced in men with high progesterone. These findings constitute the first experimental support for the affiliation account of the evolution of homoerotic motivation in humans.

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References

  • Adams, D. B., Gold, A. R., & Burt, A. D. (1978). Rise in female-initiated sexual activity at ovulation and its suppression by oral contraceptives. New England Journal of Medicine, 299, 1145–1150.

    PubMed  Article  Google Scholar 

  • Adams, H. E., Wright, L. W., & Lohr, B. A. (1996). Is homophobia associated with homosexual arousal? Journal of Abnormal Psychology, 105, 440–445.

    PubMed  Article  Google Scholar 

  • Alexander, G. M., Sherwin, B. B., Bancroft, J., & Davidson, D. W. (1990). Testosterone and sexual behavior in oral contraceptive users and nonusers: A prospective study. Hormones and Behavior, 24, 388–402.

    PubMed  Article  Google Scholar 

  • Andersen, M. L., & Tufik, S. (2006). Does male sexual behavior require progesterone? Brain Research Reviews, 51, 136–143.

    PubMed  Article  Google Scholar 

  • Bartz, J. A., Zaki, J., Bolger, N., & Ochsner, K. N. (2011). Social effects of oxytocin in humans: Context and person matter. Trends in Cognitive Sciences, 15, 301–309.

    PubMed  Google Scholar 

  • Bora, E., Yucel, M., & Allen, N. B. (2009). Neurobiology of human affiliative behaviour: Implications for psychiatric disorders. Current Opinion in Psychiatry, 22, 320–325.

    PubMed  Article  Google Scholar 

  • Bowles, S. (2009). Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors? Science, 324, 1293–1298.

    PubMed  Article  Google Scholar 

  • Brown, S. L., Fredrickson, B. L., Wirth, M. M., Poulin, M. J., Meier, E. A., Heaphy, E. D., … Schutheiss, O. C. (2009). Social closeness increases salivary progesterone in humans. Hormones and Behavior, 56, 108–111.

    PubMed Central  PubMed  Article  Google Scholar 

  • Campbell, A. (2008). Attachment, aggression and affiliation: The role of oxytocin in female social behavior. Biological Psychology, 77, 1–10.

    PubMed  Article  Google Scholar 

  • Chivers, M. L., Rieger, G., Latty, E., & Bailey, J. M. (2004). A sex difference in the specificity of sexual arousal. Psychological Science, 15, 736–744.

    PubMed  Article  Google Scholar 

  • Chivers, M. L., Seto, M. C., Lalumiere, M. L., Laan, E., & Grimbos, T. (2010). Agreement of self-reported and genital measures of sexual arousal in men and women: A meta-analysis. Archives of Sexual Behavior, 39, 5–56.

    PubMed Central  PubMed  Article  Google Scholar 

  • Ciani, A. C., Cermelli, P., & Zanzotto, G. (2008). Sexually antagonistic selection in human male homosexuality. PLoS One, 3, e2282.

    Article  Google Scholar 

  • DeWall, C. N., MacDonald, G., Webster, G. D., Masten, C. L., Baumeister, R. F., Powell, C., … Eisenberger, N. I. (2010). Acetaminophen reduces social pain. Psychological Science, 21, 931.

    PubMed  Article  Google Scholar 

  • Diamond, M. (1993). Homosexuality and bisexuality in different populations. Archives of Sexual Behavior, 22, 291–310.

    PubMed  Article  Google Scholar 

  • Diamond, L. M. (2012). The desire disorder in research on sexual orientation in women: Contributions of dynamical systems theory. Archives of Sexual Behavior, 41, 73–83.

    PubMed  Article  Google Scholar 

  • Diamond, L. M., & Wallen, K. (2011). Sexual minority women’s sexual motivation around the time of ovulation. Archives of Sexual Behavior, 40, 237–246.

    PubMed  Article  Google Scholar 

  • Eisenberger, N. I., Jarcho, J. M., Lieberman, M. D., & Naliboff, B. D. (2006). An experimental study of shared sensitivity to physical pain and social rejection. Pain, 126, 132–138.

    PubMed  Article  Google Scholar 

  • Eisenberger, N. I., & Lieberman, M. D. (2004). Why rejection hurts: A common neural alarm system for physical and social pain. Trends in Cognitive Sciences, 8, 294–300.

    PubMed  Article  Google Scholar 

  • Fessler, D. M. T. (2003). No time to eat: An adaptationist account of periovulatory behavioral changes. Quarterly Review of Biology, 78, 3–21.

    PubMed  Article  Google Scholar 

  • Fleischman, D. S., Navarrete, C. D., & Fessler, D. M. T. (2010). Oral contraceptives suppress ovarian hormone production. Psychological Science, 21, 750–752.

    PubMed  Article  Google Scholar 

  • Frye, C. A. (2006). An overview of oral contraceptives: mechanism of action and clinical use. Neurology, 66, S29–S36.

    PubMed  Article  Google Scholar 

  • Gangestad, S. W., & Thornhill, R. (1998). Menstrual cycle variation in women’s preferences for the scent of symmetrical men. Proceedings of the Royal Society B, 265, 927–933.

    PubMed Central  PubMed  Article  Google Scholar 

  • Gavrilets, S., & Rice, W. R. (2006). Genetic models of homosexuality: generating testable predictions. Proceedings of the Royal Society B, 273, 3031–3038.

    PubMed Central  PubMed  Article  Google Scholar 

  • Guida, M., Di Spiezio, S. A., Bramante, S., Sparice, S., Acunzo, G., Tomaselli, G. A., … Nappi, C. (2005). Effects of two types of hormonal contraception–oral versus intravaginal—on the sexual life of women and their partners. Human Reproduction, 20, 1100–1106.

    PubMed  Article  Google Scholar 

  • Haselton, M. G., & Gangestad, S. W. (2006). Conditional expression of women’s desires and men’s mate guarding across the ovulatory cycle. Hormones and Behavior, 49, 509–518.

    PubMed  Article  Google Scholar 

  • Hatcher, R. A., & Namnoum, A. B. (2004). The menstrual cycle. Contraceptive Technology, 18, 63–72.

  • Hill, K., & Hurtado, A. M. (2009). Cooperative breeding in South American hunter-gatherers. Proceedings of the Royal Society B, 276, 3863.

    PubMed Central  PubMed  Article  Google Scholar 

  • Hrdy, S. (2009). Meet the alloparents: Shared child care may be the secret of human evolutionary success. Natural History, 118, 24–29.

    Google Scholar 

  • Iemmola, F., & Camperio, A. C. (2009). New evidence of genetic factors influencing sexual orientation in men: Female fecundity increase in the maternal line. Archives of Sexual Behavior, 38, 393–399.

    PubMed  Article  Google Scholar 

  • Jasienska, G., & Jasienski, M. (2008). Interpopulation, interindividual, intercycle, and intracycle natural variation in progesterone levels: A quantitative assessment and implications for population studies. American Journal of Human Biology, 20, 35–42.

    PubMed  Article  Google Scholar 

  • Kinsey, A. C., Pomeroy, W. B., & Martin, C. E. (1948). Sexual behavior in the human male. Philadelphia: W. B. Saunders.

    Google Scholar 

  • Kirkpatrick, R. C. (2000). The evolution of human homosexual behavior. Current Anthropology, 41, 385–413.

    PubMed  Article  Google Scholar 

  • Kuhle, B., & Radtke, S. (2013). Born both ways: The alloparenting hypothesis for sexual fluidity in women. Evolutionary Psychology, 11, 304–323.

    PubMed  Google Scholar 

  • MacDonald, G., & Leary, M. R. (2005). Why does social exclusion hurt? The relationship between social and physical pain. Psychological Bulletin, 131, 202–223.

    PubMed  Article  Google Scholar 

  • Maner, J. K., Miller, S. L., Schmidt, N. B., & Eckel, L. A. (2010). The endocrinology of exclusion. Psychological Science, 21, 581–588.

    PubMed  Article  Google Scholar 

  • McCullough, M. E., Churchland, P. S., & Mendez, A. J. (2013). Problems with measuring peripheral oxytocin: Can the data on oxytocin and human behavior be trusted? Neuroscience and Biobehavioral Reviews, 37, 1485–1492.

    PubMed  Article  Google Scholar 

  • Mehta, P. H., & Josephs, R. A. (2010). Social endocrinology hormones and social motivation. In D. Dunning (Ed.), Social motivation (pp. 171–189). New York: Psychology Press.

    Google Scholar 

  • Miller, S. L. (2011). Hormones and social affiliation: Menstrual cycle shifts in progesterone underlie women’s attention to signs of social support. Unpublished doctoral dissertation, Florida State University, Tallahassee.

  • Muscarella, F. (1999). The homoerotic behavior that never evolved. Journal of Homosexuality, 37, 1–18.

    PubMed  Article  Google Scholar 

  • Muscarella, F. (2000). The evolution of homoerotic behavior in humans. Journal of Homosexuality, 40, 51–77.

    PubMed  Article  Google Scholar 

  • Muscarella, F. (2006). The evolution of male-male sexual behavior in humans: The alliance theory. Journal of Psychology & Human Sexuality, 18, 275–311.

    Article  Google Scholar 

  • Muscarella, F., Cevallos, A. M., Siler-Knogl, A., & Peterson, L. M. (2005). The alliance theory of homosexual behavior and the perception of social status and reproductive opportunities. Neuroendocrinology Letters, 26, 771–774.

    PubMed  Google Scholar 

  • Navarrete, C. D., Fessler, D. M. T., Fleischman, D. S., & Geyer, J. (2009). Race bias tracks conception risk across the menstrual cycle. Psychological Science, 20, 661–665.

    PubMed  Article  Google Scholar 

  • Poiani, A., & Dixson, A. F. (2010). Animal homosexuality: A biosocial perspective. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Rahman, Q., & Wilson, G. D. (2003). Born gay? The psychobiology of human sexual orientation. Personality and Individual Differences, 34, 1337–1382.

    Article  Google Scholar 

  • Reblin, M., & Uchino, B. N. (2008). Social and emotional support and its implication for health. Current Opinion in Psychiatry, 21, 201–205.

    PubMed Central  PubMed  Article  Google Scholar 

  • Rieger, G., Chivers, M. L., & Bailey, J. M. (2005). Sexual arousal patterns of bisexual men. Psychological Science, 16, 579–584.

    PubMed  Article  Google Scholar 

  • Rind, B., & Yuill, R. (2012). Hebephilia as mental disorder? A historical, cross-cultural, sociological, cross-species, non-clinical empirical, and evolutionary review. Archives of Sexual Behavior, 41, 797–829.

    PubMed  Article  Google Scholar 

  • Ross, M. W., & Wells, A. L. (2000). The modernist fallacy in homosexual selection theories: Homosexual and homosocial exaptation in South Asian society. Psychology, Evolution & Gender, 2, 253–262.

    Article  Google Scholar 

  • Savin-Williams, R. C., & Vrangalova, Z. (2013). Mostly heterosexual as a distinct sexual orientation group: A systematic review of the empirical evidence. Developmental Review, 33, 58–88.

    Article  Google Scholar 

  • Schultheiss, O. C., Dargel, A., & Rohde, W. (2003). Implicit motives and gonadal steroid hormones: Effects of menstrual cycle phase, oral contraceptive use, and relationship status. Hormones and Behavior, 43, 293–301.

    PubMed  Article  Google Scholar 

  • Schultheiss, O. C., Wirth, M. M., & Stanton, S. J. (2004). Effects of affiliation and power motivation arousal on salivary progesterone and testosterone. Hormones and Behavior, 46, 592–599.

    PubMed  Article  Google Scholar 

  • Seeman, T. E. (1996). Social ties and health: The benefits of social integration. Annals of Epidemiology, 6, 442–451.

    PubMed  Article  Google Scholar 

  • Silk, J. B., Alberts, S. C., & Altmann, J. (2003). Social bonds of female baboons enhance infant survival. Science, 302, 1231–1234.

    PubMed  Article  Google Scholar 

  • Silk, J. B., Beehner, J. C., Bergman, T. J., Crockford, C., Engh, A. L., Moscovice, L. R., … Wittig, R. M. (2010). Strong and consistent social bonds enhance the longevity of female baboons. Current Biology, 20, 1359–1361.

    PubMed  Article  Google Scholar 

  • Spector, I. P., Carey, M. P., & Steinberg, L. (1996). The Sexual Desire Inventory: Development, factor structure, and evidence of reliability. Journal of Sex and Marital Therapy, 22, 175–190.

    PubMed  Article  Google Scholar 

  • Sugiyama, L. S. (2004). Illness, injury, and disability among Shiwiar forager-horticulturalists: Implications of health-risk buffering for the evolution of human life history. American Journal of Physical Anthropology, 123, 371–389.

    PubMed  Article  Google Scholar 

  • Symons, D. (1979). The evolution of human sexuality. New York: Oxford University Press.

    Google Scholar 

  • Van Honk, J., Montoya, E. R., Bos, P. A., van Vugt, M., & Terburg, D. (2012). New evidence on testosterone and cooperation. Nature, 485, E4–E5.

    PubMed  Article  Google Scholar 

  • Van Vugt, M. (2009). Despotism, democracy, and the evolutionary dynamics of leadership and followership. American Psychologist, 64, 54–56.

    Article  Google Scholar 

  • Van Vugt, M., & Park, J. H. (2010). The tribal instinct hypothesis: Evolution and the social psychology of intergroup relations. Visions in Conflict, 1, 20.

    Google Scholar 

  • VanderLaan, D. P., Forrester, D. L., Petterson, L. J., & Vasey, P. L. (2012). Offspring production among the extended relatives of Samoan men and fa’afafine. PLoS One, 7, e36088.

    PubMed Central  PubMed  Article  Google Scholar 

  • Vasey, P. L. (1995). Homosexual behavior in primates: A review of evidence and theory. International Journal of Primatology, 16, 173–204.

    Article  Google Scholar 

  • Wallen, K., & Parsons, W. A. (1997). Sexual behavior in same-sexed nonhuman primates: Is it relevant to understanding human homosexuality? Annual Review of Sex Research, 8, 195–223.

    PubMed  Google Scholar 

  • Wallwiener, M., Wallwiener, L. M., Seeger, H., Mueck, A. O., Zipfel, S., Bitzer, J., & Wallwiener, C. W. (2010). Effects of sex hormones in oral contraceptives on the female sexual function score: A study in German female medical students. Contraception, 82, 155–159.

    PubMed  Article  Google Scholar 

  • Wilcox, A. J., Dunson, D. B., Weinberg, C. R., Trussell, J., & Baird, D. D. (2001). Likelihood of conception with a single act of intercourse: Providing benchmark rates for assessment of post-coital contraceptives. Contraception, 63, 211–215.

    PubMed  Article  Google Scholar 

  • Wirth, M. M., Meier, E. A., Fredrickson, B. L., & Schultheiss, O. C. (2007). Relationship between salivary cortisol and progesterone levels in humans. Biological Psychology, 74, 104–107.

    PubMed  Article  Google Scholar 

  • Wirth, M. M., & Schultheiss, O. C. (2006). Effects of affiliation arousal (hope of closeness) and affiliation stress (fear of rejection) on progesterone and cortisol. Hormones and Behavior, 50, 786–795.

    PubMed  Article  Google Scholar 

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Acknowledgments

The authors would like to thank Lianna Burton, Thomas Butler, Brian Fredrickson, Jennifer Gabrysh, Danielle Kaplan, Aspen Lewis, and Vera Wegricht for collecting data. This research was supported by a UCLA Council on Research grant to the second author.

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Correspondence to Diana S. Fleischman.

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Fleischman, D.S., Fessler, D.M.T. & Cholakians, A.E. Testing the Affiliation Hypothesis of Homoerotic Motivation in Humans: The Effects of Progesterone and Priming. Arch Sex Behav 44, 1395–1404 (2015). https://doi.org/10.1007/s10508-014-0436-6

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  • DOI: https://doi.org/10.1007/s10508-014-0436-6

Keywords

  • Homosexual behavior
  • Homoerotic behavior
  • Affiliation
  • Progesterone
  • Priming