Richard Dawkins on homosexuality:
"Consider human male homosexuality as a more serious example. On the face
of it the existence of a substantial minority of men who prefer sexual relations
with their own sex rather than with the opposite sex constitutes a problem for
any simple Darwinian theory. The rather discursive title of a privately circulated
homosexualist pamphlet, which the author was kind enough to send me,
summarizes the problem: 'Why are there `gays' at all? Why hasn't evolution
eliminated `gayness' millions of years ago?' The author incidentally thinks the
problem so important that it seriously undermines the whole Darwinian view of
life. Trivers (1974), Wilson (1975, 1978) and especially Weinrich (1976) have
considered various versions of the possibility that homosexuals may, at some
time in history, have been functionally equivalent to sterile workers, foregoing
personal reproduction the better to care for other relatives. I do not find this
idea particularly plausible (Ridley & Dawkins, 1981), certainly no more so than
a 'sneaky males hypothesis According to this latter idea, homosexuality
represents an `alternative male tactic' for obtaining matings with females. In a
society with harem defence by dominant males, a male who is known to be
homosexual is more likely to be tolerated by a dominant male than a known
heterosexual male and an otherwise subordinate male may be able, by virtue of
this, to obtain clandestine copulations with females. But I raise the 'sneaky male'
hypothesis not as a plausible possibility so much as a stay of dramatizing how
easy and inconclusive it is to dream up explanations of this kind ...
Homosexuality is, of course, a problem for Darwinians only if there is a genetic
component to the difference between homosexual and heterosexual individuals.
While the evidence is controversial (Weinrich 1976) assume for the sake of
argument that this is the case. Now the question arises, what does it mean to
say there is a genetic component to the difference, in common parlance that
there is a gene (or genes) 'for' homosexuality? It is a fundamental truism, of logic
more than of genetics, that the phenotypic `effect' of a gene is a concept that has
meaning only if the context of environmental influences is specified, environment
being understood to include all the other genes in the genome. A gene 'for' A in
environment X may well turn out to be a gene for B in environment Y. It is
simply meaningless to speak of an absolute, context-free, phenotypic effect of a
given gene. Even if there are genes which, in today's environment produce a
homosexual phenotype, this does not mean that in another environment, say that
of our Pleistocene ancestors, they would have had the same phenotypic effect.
A gene for homosexuality in our modern environment might have been a gene
for something utterly different in the Pleistocene. So, we have the possibility of a
special kind of 'time-lag effect' here. It may be that the phenotype which we are
trying to explain did not even exist in some earlier environment, even though the
gene did then exist." (Dawkins R., "The Extended Phenotype: The Long Reach
of the Gene," [1982], Oxford University Press: Oxford UK, 1983, pp.37-38)