Facial Structure Predicts Sexual Orientation in Both Men and Women

Abstract

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.

Perception of Sexual Orientation from Facial Structure: A Study with Artificial Face Models

“…The aim of the first experiment was to test whether people were able to discriminate between two artificial faces which differed only in the relevant metrics identified by Skorska et al (2015) as predictors of sexual orientation in both men and women, and also in both Black and White faces. The research conformed to the American Psychological Association's Ethical Principles of Psychologists and Code of Conduct.…”

“…First, FaceGen generated randomly 25 ''neutral'' faces of European males (these neutralfaceswerenotusedasstimuli).Inasecondstep,fromevery neutral face, a''gay''and a''heterosexual''version were created by manipulating the following parameters that corresponded to the three predictors (gay men vs. heterosexual men) identified in the multivariate analysis of Skorska et al (2015): Cheeks-concave/ convex, Nose-short/long, and Forehead-tilt forward/back. The parameters were manipulated in ±2 standardized units (within a total range of 20 units).…”

“…Lastly, Skorska, Geniole, Vrysen, McCormick, and Bogaert (2015) carried out an extensive study in Canada with 129 homosexual and 261 heterosexual persons of both sexes. A facial photograph was taken from each individual, which served as input in a facial modeling program (Singular Inversions, 2010).…”

“…A question that emerges from Skorska et al's (2015) work is whether the main anatomical traits statistically associated to sexual orientation could influence the perception of a person's sexual orientation by lay people. This question could be answered by means of the experimental manipulation of such traits using artificial faces as stimuli.…”

“…However, the relation between facial structure and sexual orientation has been scarcely examined. Recently, an extensive morphometric study on a large sample of Canadian people (Skorska, Geniole, Vrysen, McCormick, & Bogaert, 2015) identified three (in men) and four (in women) facial features as unique multivariate predictors of sexual orientation in each sex group. The present study tested the perceptual validity of these facial traits with two experiments based on realistic artificial 3D face models created by manipulating the key parameters and presented to Spanish participants.…”