Animals exhibiting homosexual behavior have been raising the eye brows of some people nowadays. With the recent event of Canada's gay-penguin controversy and China's zoo giving a same-sex penguin couple a chance to raise their own child splashed across every newspaper, it seems like gay animals are making their own statement in the world today.

But amidst the spot light that is focused on gay animals, scientists have an explanation as to why animals are behaving so. Back in 2009, first author of a study that dove into animals' same-sex behaviors, Nathan Bailey explained that behaviors such as courtship, mounting, or parenting are traits that are shaped by natural selection.

But aside from natural selection, selective forces, which are those that place a sudden or gradual stress on a population, are contributing to the behavior of the animals. These forces are things like weather, temperature, and geographic features, but more so are factors of social circumstances.

With homosexual behavior being explained, what are other animals that have exhibited this behavior?

Here are five animals that you would never think of being gay.