Crucially, recent studies have not found a genetic link based on sexual selection for physical traits based on symmetry. For example, Koehler et al. (2002) established that there was no difference in preference for the symmetry of male faces by females nearing conception compared to those females taking contraceptives. Similarly, Rhodes et al. (2001) found that, although there might be a link between facial symmetry and perceived health, there was no correlation between facial symmetry and actual health. So, although symmetrical faces may be attractive there have been no studies that support a link between facial symmetry and real health (Valentine et al. 2004; Rhodes 2006: 214).
In his contribution to the Antiquity debate over the viability of Kohn and Mithen's 'Sexy Handaxe Theory' (1999), Hodgson (2009: 195-8) asserts that 'symmetry is not connected with health and thus cannot have served as a sign of genetic worth'. Because I find his interpretation of the current literature on symmetry and its relationship to health and attractiveness to be flawed, I cannot accept Hodgson's argument.
Facial symmetry could play a role in "gaydar," a new study suggests. Researchers at Albright College in Reading, Pa examined how perceptions of a person's sexual orientation are influenced by facial symmetry and proportions. Self-identified heterosexuals had facial features that were slightly more symmetrical than homosexuals. And the more likely raters perceived someone as heterosexual, the more symmetrical that person's features were.
Although adult facial attractiveness ratings are replicable, even cross-culturally (see reviews and discussions in Jones & Hill, 1993, and Langlois & Roggman, 1990), there has been considerable controversy around attempts to identify in research the facial features that actually cause faces to be judged attractive or unattractive.
It has been argued that the degree of symmetry in a face may reveal the ability to canalize development in the face of stress, that is, the ability to resist parasites during development (Watson & Thornhill, 1994).
New methods reveal that averageness, or a lack of distinctness, makes someone more appealing while facial symmetry doesn't automatically make a knockout, as most people believe. Features that make a man look manly or a woman feminine can trump both averageness and symmetry, but only sometimes. And studies of faces in motion support the idea that femininity and masculinity are important to attractiveness.