Sexual orientation and the 2nd to 4th finger length ratio: evidence for organising effects of sex hormones or developmental instability?

@article{Rahman2003SexualOA,
  title={Sexual orientation and the 2nd to 4th finger length ratio: evidence for organising effects of sex hormones or developmental instability?},
  author={Qazi Rahman and Glenn D. Wilson},
  journal={Psychoneuroendocrinology},
  year={2003},
  volume={28},
  pages={288-303}
}
  • Q. Rahman, G. Wilson
  • Published 1 April 2003
  • Psychology, Biology, Medicine
  • Psychoneuroendocrinology
Fluctuating asymmetry, second to fourth finger length ratios and human sexual orientation
  • Q. Rahman
  • Psychology, Biology
    Psychoneuroendocrinology
  • 2005
Finger Length Ratio (2D:4D) and Dimensions of Sexual Orientation
TLDR
A continuous neurohormonal sexual differentiation of the brain, most notably for women, that overrides categories and results in varying dimensions of sexual orientation is hypothesized.
Prenatal Influences on Sexual Orientation: Digit Ratio (2D:4D) and Number of Older Siblings
Prenatal androgen levels are suggested to influence sexual orientation in both sexes. The 2D:4D digit ratio has been found to associate with sexual orientation, but published findings have often been
Hand Asymmetry in Heterosexual and Homosexual Men and Women: Relationship to 2D:4D Digit Ratios and Other Sexually Dimorphic Anatomical Traits
TLDR
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.
Sexual orientation and the second to fourth finger length ratio: a meta-analysis in men and women.
TLDR
It is found that heterosexual women had higher (more feminine) left- and right-hand 2D:4D than did lesbians, but there was no difference between heterosexual and gay men.
Sexual Orientation and Fluctuating Asymmetry in Men and Women
TLDR
Although elevated levels of developmental stress appear to be linked to shifts in sexual orientation, the underlying mechanism does not seem to be connected to sex-atypical prenatal hormones.
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