Comparative Study of Digit Ratios (2D:4D and Other) and Novel Measures of Relative Finger Length: Testing Magnitude and Consistency of Sex Differences across Samples

  title={Comparative Study of Digit Ratios (2D:4D and Other) and Novel Measures of Relative Finger Length: Testing Magnitude and Consistency of Sex Differences across Samples},
  author={Martin Voracek},
  journal={Perceptual and Motor Skills},
  pages={83 - 93}
  • M. Voracek
  • Published 1 February 2009
  • Psychology, Biology
  • Perceptual and Motor Skills
Digit ratios, such as the frequently studied second-to-fourth digit ratio (2D:4D), are already sexually differentiated in utero, postnatally fairly stable, and thus commonly held as possible markers for prenatal androgen levels. Based on six independent samples, totaling 381 male and 420 female subjects from different age bands, this study investigated the magnitude and cross-sample consistency of sex differences in all six possible digit ratios (2D:3D, 2D:4D, 2D:5D, 3D:4D, 3D:5D, 4D:5D) and in… 
No association between two candidate markers of prenatal sex hormones: digit ratios (2D:4D and other) and finger-ridge counts.
Some doubt is cast on the validity of retrospective pointers to prenatal androgen levels based on the associations of 2D:4D with finger-ridge counts, one such further under-researched marker.
High 3D:5D ratio: A possible correlate of externalizing and internalizing problems: An exploratory study
The 3D:5D ratio can be considered a correlate of externalizing and internalizing problems in children from the general population.
Sexual Dimorphism of Digit Ratio (2D:4D) in Madhya Pradesh
It is suggested that the 2D:4D ratio is a constant feature among different age groups in different population, which will prove useful to determine sex when more reliable means of sex estimation are not available during medicolegal examination.
Alternative Digit Ratios and Their Relationship to Prostate Cancer.
Digit ratios in two lacertid lizards: sexual dimorphism and morphological and physiological correlates
Comparing digit ratios of two Podarcis lizards among sexes, colour morphs and species concludes that digit ratios in lizards deserve attention, because they exhibit sexual dimorphism and correlate with ecologically relevant morphological and performance variables.
Mixed Sex Effects on the Second‐to‐Fourth Digit Ratio of Túngara Frogs (Engystomops pustulosus) and Cane Toads (Rhinella marina)
Evidence for sexual dimorphism of the 2D:4D scaling relationship on the front feet of túngara frogs is found, with female frogs having a larger ratio than males resulting from a relatively longer second digit on females, and further research is needed to evaluate the effect of androgens on 2D-4D in animals other than placental mammals.
Scientometric Analysis and Bibliography of Digit Ratio (2D:4D) Research, 1998–2008
Comparative citation analyses show that 2D:4D research presently is commensurate in size and importance to evolutionary psychological jealousy research, but has grown faster than the latter field.


Digit Ratios (2D:4D and other) and Relative Thumb Length: A Test of Developmental Stability
These findings mirror those reported for the second-to-fourth digit ratio (2D:4D), a likely biomarker for the organizational (permanent) effects of prenatal androgens on the human brain and body, and appear to be developmentally unstable.
Finger, Sex, and Side Differences in Fingertip Size and Lack of Association with Image-Based Digit Ratio (2D:4D) Measurements
Fingertip size was unrelated to image-based 2D:4D measurements, suggesting that fingertip size and the extent of finger and sex differences therein are unlikely to explain discrepant 2D-4D values obtained from image- based versus direct measurements.
Hand Asymmetry in Heterosexual and Homosexual Men and Women: Relationship to 2D:4D Digit Ratios and Other Sexually Dimorphic Anatomical Traits
The present evidence actually suggests that homosexuals have lower FA than heterosexuals, raising the question of whether the positive fitness components associated with low FA may contribute to selection that maintains homosexuality in a population.
A new means of measuring index/ring finger (2D:4D) ratio and its association with gender and hand preference
It is concluded that the tubes technique provides an effective and easy-to-use means of measuring finger length, which can be administered in a classroom setting and shows an association with gender.
Relative Lengths of Fingers and Toes in Human Males and Females
For both homosexual females and homosexual males, nearly all of the length ratios for fingers were intermediate to those for heterosexual females and heterosexual males; that is, the ratios of homosexual females were masculinized and those of homosexual males were hypomasculinized, but few of these differences were significant.
The development of sex differences in digital formula from infancy in the Fels Longitudinal Study
This is the first study using long-term serial data to evaluate the validity of finger length ratios as markers and finds that sex differences in the fingers of children are highly correlated with adult finger length ratio.
The use of digit ratios as markers for perinatal androgen action
  • M. McIntyre
  • Medicine, Biology
    Reproductive biology and endocrinology : RB&E
  • 2006
Current evidence for the relationship between digit ratios and prenatal androgen action is evaluated, opportunities for future validation tests are described, and the potential advantages and disadvantages of digit ratio measures are compared with more established methods for studying the effects of prenatal androgens.