Author Simon LeVay has studied neuroscience and written many books. One of his books is 'Gay, Straight, and the Reason Why: The Science of Sexual Orientation." LeVay researched what makes people gay, and he found that nature is the cause, rather than the nurture of society. He researches deeply into the characteristics of every sexual orientation, and says that there is probably not just gay, but that there are many kinds of homosexuality. I myself haven't read it, but I got an email about it. My reader says that LeVay has spoken at many PFLAG (Parents, Families&Friends of Lesbians and Gays) chapters through the years. He has also done a lot of research on the differences in the hypothalamus' (hypothalami?) of gay men and straight men. It's worth a look at, as people continue to argue about the gay 'life-style choice' and the equality of gay rights and marriage. Thank you reader for the information!!!