Pro to the question "Is Sexual Orientation Determined at Birth?"
"We will now briefly examine the various objections to homosexuality and give Buddhist rebuttals to them. The most common Christian and Muslim objection to homosexuality is that it is unnatural and "goes against the order of nature". There seems to be little evidence for this. Miriam Rothschild, the eminent biologist who played a crucial role in the fight to decriminalize homosexuality in Britain, pointed out at the time that homosexual behaviour has been observed in almost every known species of animal. Secondly, it could be argued that while the biological function of sex is reproduction, most sexual activity today is not for reproduction, but for recreation and emotional fulfillment, and that this too is a legitimate function of sex. This being so, while homosexuality is unnatural in that it cannot leads to reproduction, it is quite natural for the homosexual in that for her or him it provides physical and emotional fulfillment. Indeed, for him or her, heterosexual behaviour is unnatural."
"Homosexuality and Theravada Buddhism," Buddhanet Magazine online (accessed on May 5, 2006)