What is the reason for homosexuality in humans?
Now, first off, I am not a homophobe, or a Bible-thumper. In fact, I have several gay friends.
I'm trying to find if there is a biological basis for human homosexuality. Animal homosexuality has been proven to occur when members of the opposite sex are unavailable during the short mating seasons, so animals satisfy themselves with simulated mating at least. Although we still don't know if animals are also capable of non-mating "emotional" bonding.
In humans, several theories have been proposed. One says there is difference in brain structure, but that has not been proven I think. Second one says it is a result of social upbringing, dysfunctional families, etc. Third one says it is capable of being passed down through the genes. Fourth one says it's nature's way of eliminating weak individuals.
Humans don't need the urging of a mating season to have sex, so the unavailability of members of the opposite sex cannot be a reason. It does not serve a reproductive purpose. Emotional bonds are often formed by individuals of the same gender, but it does not lead to sexual relationships.
Please be as open and candid as you feel comfortable. This is an open discussion.