Let's see here. There are voluminous accounts of animals engaging in homosexual acts and also partnering homosexually for extended periods of time. Humans are animals (great apes, actually) who have been documented as having homosexual relationships in modern times and also pre-modern times. So, if it is documented that animals naturally engage in homosexual activity, then it is natural for humans (who are animals) to engage in homosexual activity. It's faulty reasoning to separate humans from animals and thereby make humans seem like something outside of nature. Now, as to whether or not its "okay"... that's decided in a larger social context. According to some religions homosexuality is amoral and so, for some social groups, these behaviors are not "okay". Other animals, lacking in religion, don't have a problem with homosexuality. The stigma against homosexuality is also a temporally limited social view. In ancient Athens homosexual relationships between older men and young men were considered natural and healthy, for example. Keep in mind that Athens harbored some of the greatest minds in history, so homosexuality must not be terribly abnormal. I suppose the point of this rambling answer is to say that homosexuality occurs in nature, we are part of the natural world, therefore it occurs in us, though, as with SOOO many things, it is, for a time, considered amoral by the powers that be, which does NOT mean that it is wrong in the absolute sense. So, there you go.