An analysis of the biological causes of homosexuality

Are People Born Gay? There is a popular belief that people are born either gay or straight.

An analysis of the biological causes of homosexuality

Are People Born Gay? There is a common belief among liberals that people are born either gay or straight. Conservatives tend to believe that sexual orientation is actually sexual preference, which is chosen by the individual.

This page represents a review of the scientific literature on the basis for homosexual orientation. Rich Deem Are people born gay or straight? Much of the current media sources assume the question is a solved scientific problem with all the evidence pointing toward a biological probably genetic basis for a homosexual orientation.

Contrary to this perception, the question has been poorly studied or studied poorlyalthough there is some evidence on both sides of question. In addition, many of the initial studies, which were highly touted by the media as "proof" for a biological basis for homosexuality, have been contradicted by later, more thorough studies.

This evidence falls into four basic categories: Until a few years ago, sexual orientation used to be called sexual preference.

Obviously, the two terms denote significant differences in the the manner by which sexuality develops.

Sodomy and Other "Crimes Against Nature"

A preference is something that is chosen, whereas orientation is merely something that defines us. The differences are potentially important regarding how the law applies to those who are gay. If homosexuality is not chosen, but actually is a biologically-determined characteristic over which we have no choice, then laws should not treat gays and straights differently, since homosexuality would be equivalent to one's race, over which we have no control.

Sexual orientation—brain studies Since sexual attraction begins in the brain, researchers first examined the question of sexual orientation by comparing the anatomy of brains from males and females.

These studies showed that male and female brains showed sexual dimorphism in the pre-optic area of the hypothalamus, where males demonstrated a greater than two-fold difference in cell number and size compared to females. Postmortem examination of the brains of AIDS patients vs. A subsequent study by Byne, et al.

An analysis of the biological causes of homosexuality

There was no statistically significant difference between IHAH3 sizes of male heterosexuals vs. The study also found that there were no differences in the number of neurons in the INAH3 based upon sexual orientation, although researchers found significant differences between males and females, as in other studies.

An analysis of the biological causes of homosexuality

The role of the hypothalamus in sexual orientation was further studied by Swaab, et al. Other researchers had hypothesized that differentiation of the hypothalamus occurred before birth. However, Swaab's study showed that the sexually dimorphic nucleus SDN of more than subjects decreased in volume and cell number in the females only years postnatal.

This finding complicated the findings of the brain studies, since not only chemical and hormonal factors, but also social factors, might have influenced this process. Hormonal influences Since sexual differentiation occurs within the womb, as a result of hormonal influences, it has been hypothesized that homosexuality may result from a differential hormone balance in the wombs of those who eventually exhibit a homosexual orientation.

Since hormonal levels within the womb are not available, proxies for hormonal influences have been used to examine the question of how hormonal influences might impact sexual orientation. These proxies include differences in skeletal size and shape, including the ratio of the long bones of the arms and legs relative to arm span or stature and the hand bones of adults the ratio of the length of the various phalanges.

However, in men, the index finger is usually shorter than the fourth. It has been shown that this greater 2D: It has been hypothesized that the sex difference in the 2D: A study by Williams, et al. It has been hypothesized that women exposed to more androgens in the womb tend to express a homosexual orientation.

However, since these hormone levels were never measured, one is left with the proxy of finger lengths as a substitute. Studies have found that the more older brothers a boy has, the more likely he is to develop a homosexual orientation.

Males who had two or more older brothers were found to have lower 2D:Contrary to media portrayals, a link between genetics and homosexuality is not certain.

Debate Topic: There is a biological cause to homosexuality |

Many initial, poorly designed studies have been contradicted by more recent, better designed ones. Genetics and Homosexuality: Are People Born Gay?

The Biological Basis for Sexual Orientation increased androgens resulted in development of ambiguous external genitalia. A meta-analysis of 18 CAH studies shows that % of those women suffering it seems unlikely that any homosexual genetic trait would persist in a population of .

Summary: The official explanation from the APA says that there is no consensus about what causes homosexuality. But we have observed eight predisposing factors that are common in the backgrounds of men with same-sex attraction.

Medicalizing Sexual Inversion

Final Bio Practice Exam. STUDY. PLAY. All of the following provide some support for a biological explanation for homosexuality except: a. There is a high concordance for homosexuality in monozygotic twin pairs.

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b. Female rats that share the uterus with several brothers are more likely to show male sexual behavior than female rats that . tantra sodomy and homosexuality in satanic ritual - homo-occultism, forced pederasty, tantra, sodomy, anal sex. HOMOSEXUALITY - An Analysis of Biological Theories of Causation Dr.

Tahir I jaz, M.D., Winnipeg, Canada " linkage of their behaviour to biologic causes is politically necessary, since that credo is what cements the homosexual rights groups' self-identification with genetically determined groups, like blacks and women. An .

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