People choose to be gay. They are making an immoral choice, which government should discourage. Sexual preference is biologically determined. Government should protect gay people from discrimination because homosexuality is an unalterable aspect of their identity. These two answers have something in common: With both of them, the science conveniently supports the moral decision. Perhaps sexual preference can be changed — and people have the right to engage in gay sex and have homosexual relationships if they choose to do so.

The relationship between biology and sexual orientation is a subject of research. While scientists do not know the exact cause of sexual orientation , they theorize that it is caused by a complex interplay of genetic , hormonal , and environmental influences. Biological theories for explaining the causes of sexual orientation are favored by scientists. The influence of hormones on the developing foetus has been the most influential causal hypothesis of the development of sexual orientation. The presence of the Y-chromosome in males prompts the development of testes, which release testosterone, the primary androgen receptor-activating hormone, to masculinize the fetus and fetal brain. This masculinising effect pushes males towards male typical brain structures, and most of the time, attraction to females.

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All rights reserved. The differences between heterosexual and homosexual people are as much the subject of fascinating science as they are a source of social debate. And in many cases, the former can help to inform the latter. A new study adds new weight to this evidence by using brain-scanning technology to look at the differences between the brains of gay and straight people.