In regards to the evolutionary purpose of homosexuality, I read an interesting theory, I believe by Robert Wright. Bisexuals tend to have sex earlier and have more partners. The head-start gives them an evolutionary edge. It is possible that the biological inclination towards bisexuality can also result in pure homosexuality under certain conditions.
Oh my what pure unconstrained bilge.
How do you come up with these fantastic chocolate covered Whoppers Beastie?
You see, the problem with evolutionary theory, and Darwinism proper, isn't the theory itself as an explanation for the development of life, but precisely what we have above, the attempt to use it as an direct causal explanation for
everything, including whatever it is we wish to indulge in ourselves behaviorally or whatever behavior in others we wish to justify socially, morally, and politically.
Biological determinism is another wonderful tool for the cultural Left because it employs the mechanisms of evolution to put an end to philosophical thought (and actual debate) and the idea that their are any number of problems within the human condition that cannot be, and should not be, answered by science.
Everything is just accepted as it is because it is. All is a function of evolution (at least, those things we want to affirm and support), and nothing within the realm of human behavior is anything but a derivative
epiphenomena of evolutionary development.
Case closed. All argument ended. All moral, ethical, and religious questions answered.
In the name of Dawkins, Sagan, and the Holy genome, amen.