To say that homosexuality is "unnatural" may lead to a big debate as biologists and researchers have found out that homosexuality is quite common in the animal kingdom, especially among herding animals. The dwarf chimpanzee is the most famous homosexual animal as that the entire species is bisexual.

The issue of homosexuality in animals has always been controversial as it asserts the points to the naturalness of homosexuality in humans. Others would then find it nonsensical to use animal behavior to justify morality in humans.

The correct usage of the term homosexual as applied to animals is the exhibition of all sexual behavior: genital stimulation, sexual display behavior, copulation and mating games between animals of the same sex.

Moving further, animals often form long-term same-sex relationships just like humans.  There are species where heterosexual pair-bonds don't normally form for long.  Good examples are bottlenose dolphins, which are not known to form heterosexual pair bonds, but which do in fact form homosexual pair bonds that often stay very long.

Homosexuality is a social phenomenon and is most widespread among animals with a complex herd life. It is common for lions to form homosexual acts as male lions often bond together with their brothers to lead the pride. To ensure loyalty, they strengthen the bonds by often having sex with each other.

According to Peter Boeckman of University of Oslo, animals have sex because they have the desire to, just like humans. He added that for some animals, homosexual behavior is rare. Some have sex with the same sex only a part of their lives, making the human pattern of bisexuality appear in animals.  

A good example is the male walruses that often form homosexual pair bonds and have sex with each other outside of the breeding season, but will return to a heterosexual pattern when the breeding season come back. Other animals, such as the dwarf chimpanzee, practice homosexuality throughout their lives. He also observed that 1,500 animal species practice homosexuality.

Gay rights opponents would try to explain away the naturalness of animal homosexuality by claiming that homosexuality in animals is the result of a shortage or unavailability of heterosexual mates. They neglect the fact that homosexual behavior occur even more frequently among balanced populations than skewed ones.

Another hypothesis formed in the claim that the same sex partner is unable to identify a member of the opposite sex. Again, they haven't observed that there are obvious differences between sexes in most animals: body color, shape or sizes. They also neglect the fact that bisexual animals, it has only one set of courtship rituals when courting homosexual versus heterosexual partners. This would not happen if the problem were a case of mistaken identity.

This just proves that there is a wide range of homosexual behaviors in the animal kingdom, and that Same sex partners engage into different ways of sexual expression. Is this fact enough to establish away the thought of criminalizing something that is natural? The fact is that: humans are animals as well.