Facial Structure Predicts Sexual Orientation in Both Men and Women
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Biological models have typically framed sexual orientation in terms of effects of variation in fetal androgen signaling on sexual differentiation, although other biological models exist. Despite marked sex differences in facial structure, the relationship between sexual orientation and facial structure is understudied. A total of 52 lesbian women, 134 heterosexual women, 77 gay men, and 127 heterosexual men were recruited at a Canadian campus and various Canadian Pride and sexuality events. We found that facial structure differed depending on sexual orientation; substantial variation in sexual orientation was predicted using facial metrics computed by a facial modelling program from photographs of White faces. At the univariate level, lesbian and heterosexual women differed in 17 facial features (out of 63) and four were unique multivariate predictors in logistic regression. Gay and heterosexual men differed in 11 facial features at the univariate level, of which three were unique multivariate predictors. Some, but not all, of the facial metrics differed between the sexes. Lesbian women had noses that were more turned up (also more turned up in heterosexual men), mouths that were more puckered, smaller foreheads, and marginally more masculine face shapes (also in heterosexual men) than heterosexual women. Gay men had more convex cheeks, shorter noses (also in heterosexual women), and foreheads that were more tilted back relative to heterosexual men. Principal components analysis and discriminant functions analysis generally corroborated these results. The mechanisms underlying variation in craniofacial structure—both related and unrelated to sexual differentiation—may thus be important in understanding the development of sexual orientation.
KeywordsSexual orientation Sexuality Faces Facial structure Sexual differentiation
The first two authors contributed equally to this work. Thank you to K. Walczyk, L. Jamieson, K. Zeller, C. Davis, K. Spin, J. Bramley, S. Norgaard, and A. DesRoches for assistance with the collection of the original database. Thank you to D. Molnar for assistance with statistical analyses. Thank you to the three anonymous reviewers and the Editor for insightful comments related to this article. This research was supported by Social Sciences and Humanities Research Council grants to A. F. Bogaert [335-737-042] and to C. M. McCormick [334-222-005].
- Carré, J. M., & McCormick, C. M. (2008). In your face: Facial metrics predict aggressive behaviour in the laboratory and in varsity and professional hockey players. Proceedings of the Royal Society B: Biological Sciences, 275, 2651–2656. doi: 10.1098/rspb.2008.0873.PubMedCentralPubMedCrossRefGoogle Scholar
- Cohen, J., Cohen, P., West, S. G., & Aiken, L. S. (2003). Applied multiple regression/correlation analysis for the behavioral sciences (3rd ed.). Mahwah, NJ: Erlbaum.Google Scholar
- Enlow, D. H. (1982). Handbook of facial growth (2nd ed.). Philadelphia: W.B. Saunders.Google Scholar
- Jelenkovic, A., Poveda, A., Susanne, C., & Rebato, E. (2010). Common genetic and environmental factors among craniofacial traits in Belgian nuclear families: Comparing skeletal and soft-tissue related phenotypes. Journal of Comparative Human Biology, 61, 191–203. doi: 10.1016/j.jchb.2009.10.003.PubMedCrossRefGoogle Scholar
- LeVay, S. (2010). Gay, straight, and the reason why: The science of sexual orientation. New York: Oxford University Press.Google Scholar
- Meindl, K., Windhager, S., Wallner, B., & Schaefer, K. (2012). Second-to-fourth digit ratio and facial shape in boys: The lower the digit ratio, the more robust the face. Proceedings of the Royal Society B: Biological Sciences, 279, 2457–2463. doi: 10.1098/rspb.2011.2351.PubMedCentralPubMedCrossRefGoogle Scholar
- Singular Inversions. (2010). FaceGen Modeller, Version 3.5. http://www.facegen.com
- Tabachnick, B. G., & Fidell, L. S. (2007). Using multivariate statistics (5th ed.). Boston, MA: Pearson Education.Google Scholar