DEPARTMENT OF ANTHROPOLOGY- HUMAN BEHAVIOR RESEARCH | face and body

Second to fourth digit ratio, testosterone and perceived male dominance

Nick Neave*, Sarah Laing*, Bernhard Fink**
& John T. Manning***

*Human Cognitive Neuroscience Unit, School of Psychology and Sport Sciences, Northumbria University, Newcastle upon Tyne, UK
**Ludwig-Boltzmann-Institute for Urban Ethology, Vienna, Austria
***University of Central Lancashire, Department of Psychology, UK

Previous studies have shown that male faces with extreme features associated with testosterone are perceived as dominant and masculine. Women have been reported to prefer more masculinized male faces as they may consider testosterone markers to be an 'honest' indication of good health, and such considerations may underlie their aesthetic preferences. However, pronounced testosterone facial markers are also associated with dominance, and several negative personality traits. This suggests that female aesthetic preferences may be an adaptive compromise between positive attributes associated with higher than average testosterone, and negative attributes associated with more extreme masculinization. This current study attempts to clarify the role of hormone markers in female perceptions of dominance, masculinity and attractiveness, in male facial images. Recent evidence suggests that the relative length of the 2nd to 4th finger (2D : 4D ratio) is a pointer to prenatal testosterone levels and may thus serve as a window to the prenatal hormonal environment. We measured 2D : 4D in a sample of male college students and took salivary samples to analyse circulating levels of testosterone. Women rated facial images of these males for dominance, masculinity and attractiveness. Our results show that male 2D : 4D was significantly negatively related to perceived dominance and masculinity but not attractiveness. Circulating testosterone levels were not related to dominance, masculinity or attractiveness. These findings suggest that: (i) high prenatal levels of testosterone serve to 'organize' male facial features to subsequently reflect dominance and masculine characteristics presumably activated during puberty; and (ii) attractiveness is not directly related to testosterone levels. We conclude that facial dominance and masculinity reflect a male's perceived status rather than his physical attraction to women.

The original paper has appeared in Proceedings of the Royal Society of London B: Biological Sciences, 270, 2167-2172, and is entitled:

Selected references & further reading:

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MANNING, J.T. (2002). Digit ratio: a pointer to fertility, behaviour and health. New Jersey: Rutgers University Press.
BBC News on digit ratio & heart attack (Audio) | BBC News on digit ratio & sexual orientation (Audio)

MANNING, J. T., BARON-COHEN, S., WHEELWRIGHT, S. & SANDERS, G. (2001). The 2nd to 4th digit ratio and autism. Developental Medicine & Child Neurology, 43(3), 160-164.

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UNIVERSITY OF VIENNA