The natural bell curve variation that occurs in biology and sociology everywhere, explains the variable spectrum of expression. LeVay's research suggested that the hypothalamus of gay men is different from straight men. Daryl Bema social psychologist at Cornell Universityhas theorized that the influence of biological factors on sexual orientation may be mediated by experiences in childhood. Archived from the original PDF on More research is needed in order to understand the requirements and timing of the development of the oSDN and how prenatal programming effects the expression of mate choice in adulthood.
Genes, Brain and Behavior.
Excess of counterclockwise scalp hair-whorl rotation in homosexual men.
A later analysis by Hu et al. Their results suggested that "genes predisposing to homosexuality may confer a mating advantage in heterosexuals, which could help explain the evolution and maintenance of homosexuality in the population". Some researchers state that solid scientific support for this is lacking. In other words, every identical twin of a homosexual subject was also homosexual, while this was not the case for non-identical twins. He obtained brains from 41 deceased hospital patients. According to Dean Hamer and Michael Bailey, genetic aspects are only one of the multiple causes of homosexuality. From Wikipedia, the free encyclopedia.
Furthermore, the SCN of homosexual males is extremely large both the volume and the number of neurons are twice as many as in heterosexual males. A number of twin studies have attempted to compare the relative importance of genetics and environment in the determination of sexual orientation. They conjure up the specter of the surgical or chemical "rewiring" of gay people, or of abortions of fetal homosexuals who have been hunted down in the womb. Sexual orientation and science Biology of gender Behavioural genetics. Sexual orientations Asexual Bisexual Heterosexual Homosexual.