Very interesting and thanks for the eloquent information.
So eye colour is a bad example, true. But what about to be left handed? Could this be caused by the same circumstances? Or did they find a genetic marker for this feature?
And don't be 'surprised'.
I never stated homosexuality to be a 'wanted feature' by nature but a natural state. I guess the feature - if wanted - would be the end of our species.
Not that this would be a problem for the planet. Maybe your explanation is a security feature? The unwanted police behaviour may be triggered by overpopulation?
The mother may live in very cramped surroundings, in a climate of war and fight for resources and she breeds a child uninterested in reproduction to regulate the overpopulation?
In any case it is nothing to blame the gay persons for and we should accept and consider their sexual orientation as completely equaly righted - including marriage and child adoption.