Facial masculinity does not appear to be a condition-dependent male ornament and does not reflect MHC heterozygosity in humans.
Recent studies have called into question the idea that facial masculinity is a condition-dependent male ornament that indicates immunocompetence in humans. We add to this growing body of research by calculating an objective measure of facial masculinity/femininity using 3D images in a large sample (n = 1,233) of people of European ancestry. We show that facial masculinity is positively correlated with adult height in both males and females. However, facial masculinity scales with growth similarly in males and females, suggesting that facial masculinity is not exclusively a male ornament, as male ornaments are typically more sensitive to growth in males compared with females. Additionally, we measured immunocompetence via heterozygosity at the major histocompatibility complex (MHC), a widely-used genetic marker of immunity. We show that, while height is positively correlated with MHC heterozygosity, facial masculinity is not. Thus, facial masculinity does not reflect immunocompetence measured by MHC heterozygosity in humans. Overall, we find no support for the idea that facial masculinity is a condition-dependent male ornament that has evolved to indicate immunocompetence.
['Zaidi|Arslan A|AA|0000-0002-2155-8367', 'White|Julie D|JD|0000-0002-2235-4817', 'Mattern|Brooke C|BC|', 'Liebowitz|Corey R|CR|', 'Puts|David A|DA|', 'Claes|Peter|P|', 'Shriver|Mark D|MD|']
D000293:Adolescent D000328:Adult D001504:Beauty D002755:Choice Behavior D005145:Face D005260:Female D006579:Heterozygote D006801:Humans D007121:Immunocompetence D008285:Major Histocompatibility Complex D008297:Male D057228:Masculinity D010829:Physiological Phenomena D012727:Sex Characteristics D012725:Sexual Behavior D055815:Young Adult
facial masculinity MHC heterozygosity human evolution immunocompetence handicap hypothesis sexual selection