[ExI] sex - was Re: The smart-stupid dimension

[SR Ballard]

> Genes don't care if we have fun or not, they only care about getting passed
> onto the next generation. So it's not surprising that genes would endow
> their gene delivery vehicles (us) with a revulsion at the very thought of
> mixing our genes with a very close relative because that would increased the
> likelihood the resulting offspring would not live long enough to reach
> reproductive age.

Well, what are we counting as "very close relatives"? As far as first
and second cousins go, there are more than a handful cultures which
practice marriage with first cousin, and very many more with second
cousins. While I believe it was not common in England at the time, Mr.
& Mrs. Darwin were first cousins and got married, though they had to
jump through some hoops to do so.

The grossness/repulsion factor also seems to be related to
socialization. Perhaps uncommon, but there seems to be some kind of
attraction between biologically related people who did not grow up
knowing each other (the theory of Genetic Sexual Attraction).

However, I don't want to overstate my point. People have an
unconscious preference towards those with dissimilar immunity genes,
the evidence backs this up. Interestingly, there is some evidence that
women who take the Pill actually experience the opposite: attraction
to makes that are genetically more similar.
http://rspb.royalsocietypublishing.org/content/275/1652/2715


> If someone is unrelated to me my genes would say it's OK
> to mix my genes with her if she looked healthy, but my genes don't want
> competition so they would be prudish about 2 people unrelated to each other
> and unrelated to me having sex and producing offspring.  My genes don't want
> me to have sex with a close relative but they encourage me to be altruistic
> to them because, being relatives, we have many genes in common.

I think it would be more true to say that my genes don't want
competition, but they do want to spread. So I want to take as many
partners as I can, but I don't want my partner(s) to take others.

So in light of that, prudishness and the institution of marriage may
be the solution to the above intentions, as fighting over sexual
partners would cause a lot of social conflicts. By limiting Men/Women
to X number of partners, with social and perhaps legal sanctions if
they don't comply, society reduces the time loss and destruction
caused by these kinds of fights.