Biodemographic and Physical Correlates of Sexual Orientation in Men

@article{Schwartz2010BiodemographicAP,
  title={Biodemographic and Physical Correlates of Sexual Orientation in Men},
  author={Gene Schwartz and Rachael M. Kim and Alana B. Kolundzija and Gerulf Rieger and Alan R. Sanders},
  journal={Archives of Sexual Behavior},
  year={2010},
  volume={39},
  pages={93-109}
}
To better understand sexual orientation from an evolutionary perspective, we investigated whether, compared to heterosexual men, the fewer direct descendants of homosexual men could be counterbalanced by a larger number of other close biological relatives. We also investigated the extent to which three patterns generally studied separately––handedness, number of biological older brothers, and hair-whorl rotation pattern––correlated with each other, and for evidence of replication of previous… 

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References

SHOWING 1-10 OF 126 REFERENCES
Development and familiality of sexual orientation in females
TLDR
The possibility of using developmental criteria to differentiate between inherited and cultural sources of variation in female sexual orientation is discussed, with a focus on sisters, daughters, nieces, and female cousins through a paternal uncle.
Evidence of familial nature of male homosexuality.
TLDR
There is a significant familial component to male homosexuality, with heterosexual index men having about as many homosexual brothers as would be predicted given national prevalence figures for homosexuality, but homosexual index men had about four times as many gay brothers, although in both cases most brothers were heterosexual.
How Many Gay Men Owe Their Sexual Orientation to Fraternal Birth Order?
TLDR
This work derived generalized forms of two epidemiological statistics, the attributable fraction and the population attributable fraction, which quantify the relationship between a condition and prior exposure to an agent that can cause it and showed that roughly 1 gay man in 7 owes his sexual orientation to the fraternal birth order effect.
A twin registry study of male and female sexual orientation
Monozygotic (MZ), same‐sex dizygotic (DZ), and opposite‐sex (OS) twins from the Minnesota Twin Registry responded to a sexual orientation survey. Using the relative frequencies of heterosexuals,
Heritable factors influence sexual orientation in women.
TLDR
Heritabilities were significant using a wide range of assumptions about both the base rate of homosexuality in the population and ascertainment bias and self-reported history of childhood gender nonconformity.
Birth Order, Sibling Sex Ratio, Handedness, and Sexual Orientation of Male and Female Participants in a BBC Internet Research Project
TLDR
The results yielded some evidence confirming prior findings that non-right-handedness is associated with homosexuality in men and women, that older brothers increase the odds of homosexuals in men, and that the effect of older brothers on sexual orientation is limited to right-handed men.
Familiality of female and male homosexuality
TLDR
Results were most consistent with the possibility that similar familial factors influence male and female sexual orientation, but further work is needed using large samples and more careful methods before the degree of cofamiliality ofmale and female homosexuality can be resolved definitively.
Family Size in White Gay and Heterosexual Men
TLDR
The main outcome measure was the number of each man’s uncles and aunts, first cousins, siblings, nephews and nieces, and his own children, and increased fecundity in the relatives of gay men was found.
A Family History Study of Male Sexual Orientation Using Three Independent Samples
TLDR
The results differed significantly with those of some prior studies, but they do not exclude the possibility of moderate X-linkage for male sexual orientation, and the importance of familial factors for male homosexuality.
Sexual orientation and handedness in men and women: a meta-analysis.
TLDR
The results support the notion that sexual orientation in some men and women has an early neurodevelopmental basis, but the factors responsible for the handedness-sexual orientation association require elucidation.
...
1
2
3
4
5
...