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From: riddle@ut-sally.UUCP (Prentiss Riddle)
Newsgroups: net.motss,net.bio
Subject: Re: gay genes
Message-ID: <1901@ut-sally.UUCP>
Date: Mon, 13-May-85 14:42:30 EDT
Article-I.D.: ut-sally.1901
Posted: Mon May 13 14:42:30 1985
Date-Received: Wed, 15-May-85 02:20:59 EDT
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Reply-To: riddle@ut-sally.UUCP (Prentiss riddle)
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Leader-Of-The-Pack: "Bob"

> Any gene that caused homosexuality would not survive.  It doesn't
> matter if gay people have children.  They have LESS children, and that
> is all it takes.  Any trait that reduces the likelihood of reproduction
> will disappear exponentially.

Not necessarily.  Remember, the genes found in an individual member of a
species are found to varying degrees among the relatives of that individual
as well.  It is quite possible for there to be traits -- especially
recessive ones -- which cause an individual to be less likely to produce
offspring, but which are beneficial to the individual's kin and therefore
survive into future generations indirectly.

There are several very different examples of this which come to mind.  One
which I can (fuzzily) recall from high school biology is sickle cell anemia,
which is deadly when an individual has two of the genes in question but
highly beneficial (in tropical climates) to those who only have one, as it
reduces susceptibility to malaria.  In this case, the gene has very
different consequences in heterozygous and in homozygous form.

More interesting are species with neuter forms, such as the social insects.
Drone ants don't breed, but they certainly contribute to the survival of
their genes anyway.

And a final example which is known to be highly developed in humans is what
sociobiologists call "altruism."  When, say, a parent bird or mammal dies
protecting its young from a predator, it is destroying its own specific set
of genes but increasing the chances of survival for the portion of its genes
carried by its children.  This can apply to less closely related kin as
well, and in the case of humans certainly does.  (Humans are so altruistic
that they are often willing to die for other humans who are hardly related
at all, or even for an idea or a symbol.)

Could any of this apply to a hypothetical "gay gene"?  Maybe.  The gene
could be linked by chance to other, desirable traits, or it could even be
desirable in and of itself in ways we don't understand.  (Some wild-eyed
speculators have noted the alleged creativity common among gays, and
credited homosexuals as being the "wild cards" among the human race that
give the species much of its ability for innovation.)

Or perhaps the prevalence of homosexuality among humans (10% is much higher
than in many species) is a spin-off of the general "sexiness" of the human
race: we as a species are much more sex-oriented than any of our relatives,
and use sex for all sorts of things other than just reproduction.  If sex
evolved as part of the glue that keeps primates and especially humans
together in social groups, mightn't homosexuality be just another (perhaps
highly beneficial) sort of glue?  Maybe bands of early hominids that weren't
strictly hetero in their sexual attachments functioned better as groups than
those that didn't.

Who knows?  I certainly don't.  But I think that what constitutes a survival
characteristic is far too complex a question for us to rule out the
possibility of a genetic component to homosexuality.

--- Prentiss Riddle ("Aprendiz de todo, maestro de nada.")
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--- riddle@ut-sally.UUCP, riddle@ut-sally.ARPA, riddle%zotz@ut-sally