One of the (very) discussed scientific theories in an attempt toexplain homosexuality and heterosexuality is based on in utero testosterone levels. Explained by the Belgian biologist Jacques Balthazart from several studies, this postulate presumes that it iswhether or not a embryonic testosterone surge which would subsequently determine sexual attraction towards individuals of the same or opposite sex.
And a new study seems to join this theory. She suggests that the length of some fingers relative to each other would provide information about straight or homosexuality. Exposure to testosterone in the womb would indeed affect the difference in length between index and ring fingers. The index and ring fingers of most women would be similar in size, while the index and ring fingers would show a noticeable difference in most men, due to the occurrence of the testosterone spike in utero, at a key moment in embryonic life.
Conducted by the University of Essex (United Kingdom) and published in the journal Archives Of Sexual Behavior, the study was conducted with identical twins (18 pairs of twins and 14 pairs of twins), one of whom is homosexual. By comparing the difference in size between index and ring finger, scientists found that on average, lesbians had more “typical” male hands than their heterosexual twin sisters. The same goes for the gay twin, but with a non-significant difference with the heterosexual brother.
“Since identical twins, who share 100% of their genes, can differ in their sexual orientation, factors other than genetics must be taken into account. Research suggests that our sexuality is determined in the womb and depends on the amount of male hormone we are exposed to or the way our bodies respond to this hormone, with people exposed to higher levels of testosterone being more likely to be bisexual or gay. Due to the link between hormone levels and the difference in finger lengths, looking at someone’s hands could provide a clue about their sexuality.”Said Dr. Tuesday Watts, co-author of the study.
Note that correlation is not causation, and it is therefore still premature to assert with certainty someone’s sexual orientation in view of the difference in length between index and ring finger.
Source: Edinburg News
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