Is Digit Ratio (2D:4D) Related to Masculinity and Femininity? Evidence from the BBC Internet Study

Abstract

Research on association between digit ratio (2D:4D; a putative correlate of prenatal sex steroids) and mental masculinity/femininity (Masc/Fem) has reported mixed findings. This may be due to differences in protocols for assessing 2D:4D and Masc/Fem across studies. Here, we consider the relationship between direct self-measured 2D:4D and occupational preference, and self-rated Masc/Fem from participants in a large internet survey (i.e., the BBC internet study). Men and women provided information about interest in occupations and rated themselves on Masc/Fem. There were significant sex differences in 2D:4D and occupational preference. Men reported lower 2D:4Ds and higher interest in “male-type” occupations, while women reported a stronger preference for “female-type” occupations and a higher 2D:4D. Correlations between 2D:4D and a composite score for “male-type” occupations were significantly negative for heterosexual men and women and for bisexual women. A composite score of “female-type” occupations showed only one positive correlation for 2D:4D (female right 2D:4D). Digit ratio was also negatively related to a composite measure of the difference between “male-type” and “female-type” occupations, and for individual occupations, the pattern of negative correlations was confirmed for “male-type” occupations. Self-rated Masc/Fem showed a significant sex difference (women