>> similar effect with homosexuals tending to contribute to tribal fitness thus enhancing reproductive fitness of the tribe.
If they want to reproduce, don't they have to search outside their tribe for a sperm/egg donor and possibly surrogate? So at least 50% or more of their reproductive health comes from outside the tribe?
I'm talking about behaviors and you are talking about desires. These are very different contexts.
Attempts to characterize behavior show homosexuals more commonly staying with parents and supporting relatives. The usual explanation for this is that they are not interested or able to compete in the usual mating and paring rituals. It isn't that they want to reproduce so much as they want to contribute to the tribe and in doing so result in the reproductive capacity of the entire tribe being increased.
If they want to reproduce, don't they have to search outside their tribe for a sperm/egg donor and possibly surrogate? So at least 50% or more of their reproductive health comes from outside the tribe?