What do gay horses eat?

I don't remember, but apparently there really are gay horses. And gay giraffes, sheep, dolphins, pigs, birds... some 450 species exhibit gay behavior. This article in Seed details some theories why. It also contains the following paragraph.

Giraffes have all-male orgies. So do bottlenose dolphins, killer whales, gray whales, and West Indian manatees. Japanese macaques, on the other hand, are ardent lesbians; the females enthusiastically mount each other. Bonobos, one of our closest primate relatives, are similar, except that their lesbian sexual encounters occur every two hours. Male bonobos engage in “penis fencing,” which leads, surprisingly enough, to ejaculation. They also give each other genital massages.

Yeah, you're gonna go read that right now, aren't you.