“How could “genetic” homosexuality maintain itself in the population?”
There is another objection to the notion of a genetically
induced homosexuality. An unreproductive behavior
cannot be “genetic” and also continue to exist in the population. According to mainstream genetics,
genetically enforced homosexuality (exclusively same-sex
sex) would die out of the population in several generations.
Here’s how. A gene is retained in the gene pool when an average of at least one child is born to every
adult having that gene (one child per person). As unlikely
as it sounds, surveys show that of persons classifying
themselves as exclusively homosexual, one in five has a child. At that rate, a homosexual gene, or
genes, could not be replaced.
But most homosexuals may be married (see Chapter Two). Wouldn’t this preserve any homosexual
gene or genes? Not necessarily. A married homosexual is (usually) bisexual. According to surveys, bisexuals
have an average
of 1.25 children each.
On its own, that’s enough to replace the adult gene or genes, but the
average total number of children produced by bisexuals and exclusive homosexuals still comes to less than
one child per person
- 0.9. At that rate, any homosexual gene or genes would still slowly but inevitably breed
out of the population.
http://www.mygenes.co.nz/Ch1.pdf
Interesting. Is this mechanism applicable to other rare genetic diseases as well?