Homosexuality is unnatural? Then explain these examples...

One of the canards most frequently repeated by anti-gay conservatives is the notion that "homosexuality is unnatural." But scientists have observed homosexuality in over 1,500 species, and well-described in at least one-third of those. LiveScience has an interesting online presentation titled Gay Animals: Alternate Lifestyles in the Wild which includes a List of Top 10 Ocuurences of Homosexuality in Animals:

1. Black swans
   Homosexual couples account for up to 20 percent of all pairings annually.
2. Giraffes
   According to one study, one in every 20 male giraffes will be found necking with another male at any instant.
3. Bottlenosee dolphins
   The homosexual activities of these mammals include oral sex during which time one dolphin stimulates the other with its snout.
4. Guianan cock-of-the-rock
   Almost 40 percent of the male population of this brightly colored perch engage in a form of homosexuality, with a small percentage never copulating with a female.
5. Walrus
   The older males are typically bi-sexual, mating with females during breeding season and copulating with other males the rest of the year.
6. American bison
   More than 55 percent of mounting in young males is with the same gender.
7. Kob antelope
   Homosexual mounting encompasses almost 9 percent of all sexual activities within these hoofed mammals in the wild.
8. Gray whale
   In slip-and-slide orgies, as many as five males roll around, splashing water, and rubbing their bellies against each other so that their genitals are touching.
9. Japanese macaques
   Female macaques form intense bonds with each other and are serially monogamous, meaning they only have one sexual partner at a time.
10. Bonobo chimpanzees
    Considered the closest living relative to humans, nearly all of these peace-loving apes are bisexual, with about two thirds of the homosexual activities occurring amongst females.

A reader points out this interesting article in USA Today (!) which hypothesizes the following correction running in a newspaper:

Correction: Despite what you might have read, heard or been taught throughout your churchgoing life, homosexuality is, in fact, determined at birth and is not to be condemned by God's followers.

The central thesis of the Op-Ed is that religion risks losing its moral authority by making absolutist claims about the morality of homosexuality which are based on selective textual fidelity. The author, a Baptist minister, points out that years ago the Catholic Church staked its reputation on the notion that Earth was the center of the Solar System and tortured one of humanity's most brilliant minds (Galileo) to get him to conform his understanding of the Universe to their view. The Church was spectacularly wrong then, so it is not surprising that clearly thinking people should expect the chruch to be right about homosexuality now.