Finger lengths, 2D:4D ratios, and their relation to gender-related personality traits and the Big Five.Biol Psychol. 2006 Jan; 71(1):116-21.BP
Finger lengths and the ratio of index finger to ring finger length (2D:4D) may be markers of gonadal hormone exposure. The current study investigated possible associations between absolute finger lengths, 2D:4D ratios, and gender-related personality traits in over 2000 participants. Regression analyses showed no associations between men's 2D:4D ratios and gender-related personality traits and weak associations between women's 2D:4D ratios and gender-related occupational preferences. Men's absolute finger lengths were weakly associated with self-ascribed masculinity, and women's absolute finger lengths were weakly associated with masculine occupational preferences. Big Five personality traits were assessed in a subsample of over 1000 participants. Analyses showed a weak positive association between 2D:4D and extraversion and a weak negative association between 2D:4D and openness to experience. Absolute finger lengths showed a weak negative association with agreeableness and a tendency to be associated with women's but not men's openness. Overall, associations between finger-length measures and personality were weak and inconsistent.