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Is heterosexuality the only normal kind of sexual orientation?
With chimps, about a third of all "mounting activity" occurs between males...
If we define heterosexuality as an exclusive attraction to members of the opposite sex, then, no, it is not the only normal kind of sexual orientation. Same-sex attraction, as well as same-sex sexual activity, occurs in every country and every culture on earth, even in countries that punish it by death.
It also occurs throughout the animal kingdom, as is documented in a 700-page book called Biological Exuberance: Animal Homosexuality and Natural Diversity, written by biologist Dr. Bruce Bagemihl, and also in a book called Evolution's Rainbow, written by Dr. Joan Roughgarden, a professor of biological sciences at Stanford University.
When you look at the two animals species most closely related to humans - chimpanzees and bonobos, each of which shares 98.5 percent of its genes with humans - the point becomes even clearer. With chimps, about a third of all "mounting activity" occurs between males; if all chimps were heterosexuality, there would be no mounting activity between males.
With bonobos, the picture is even clearer. Dr. Bagemihl and other experts report that virtually all bonobos who have been observed either in captivity or in the wild are bisexual. In other words, they engage is sexual activity with both males and females.
Bonobos engage is more same-sex sexual behavior than chimps do, and there is another important different between bonobos and chimps: Bonobos are far more peaceful than chimpanzees - quite possibly because of the high rate of same-sex sexual behavior. Far from being "abnormal," same-sex sexual behavior in the animal kingdom might serve an important purpose: keeping the peace, especially between males who might otherwise attack each other.
Think about that. The bonobos, one of our two closest primate relatives, are all blatantly bisexual. When you add to that the universality of same-sex sexual behavior observed among hundreds of animal species and the universality of same-sex sexual behavior in all human cultures, the only honest conclusion you can draw is that heterosexuality is definitely not the only normal form of sexual expression. The claims that some religious fanatics make about sexual orientation - that same-sex attraction is abnormal or even a sign of "sickness" - are completely false.
One of the claims made by people who try to suppress same-sex sexual behavior is that such behavior is "unnatural" because it doesn't promote sexual reproduction. But studies conducted in the U.S., the U.K., and Japan have shown that it is common for both males and females who engage in same-sex sexual behavior to have offspring. In one study conducted in Japan with 655 men who identified themselves as either homosexual or bisexual, 83 percent of them had had children. Just because someone engages in same-sex sexual behavior, that doesn't stop them from producing children.
Over and over, when you look at the actual facts of the matter and set aside religious or societal prejudice, same-sex sexual attraction not only looks normal, it actually looks good.