I shouldn't assume that should I?
Anyhow not only are homosexuals a minority today, but they do also have a harder time getting children (adoption, or cloning if you want to go sci-fi, are not that easy compared to natural procreation), if it was a matter of passing on one's values, if it was a social trend so to speak, then they would still be a minority, since they don't get the same chance to further their beliefs.
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