Friday 8 August 2008

Evolution and homosexuality (6)

(Continued)

Logic says that there is an upper limit to the number of people that can live on the planet, whether this is ten billion or a hundred billion I have no idea, or whether this will be reached in a few decades or not for millennia.

But let's assume that one day that limit is reached, and everything that can be invented or discovered has been, societies have organised themselves to maximum efficiency, and everybody can live a happy and peaceful life. At this stage, there is no evolutionary advantage to couples having more than two children (assuming child mortality is eliminated). But some people like having lots of children (fair enough, this urge is far more ancient than the dim knowledge that we have reached some sort of neo-Malthusian equilibrium), so Nature will step in again, to ensure that even though some couples have more than two children, they will not have more than four grandchildren because some of their children will be, er, homosexual.

So there you have it, the subtle evolutionary advantages of homosexuality will always be equal and opposite to the obvious evolutionary disadvantages that gays tend not to have children, no matter whether you are looking at pre-history or the distant future.

Final episode tomorrow, then I'm done.

3 comments:

Jock Coats said...

These have all been very interesting, and I can't wait for the denuement!

My opinion on all this has changed quite a lot over time. I was pretty firmly in the "gay gene" camp, or maybe the gay "camp gene"...:) But, while there is perhaps more and more evidence, it is all circumstantial so far as I can see. I just think that our modern "sexualities" are really socio-cultural constructs and that real human sexuality is inherently more flexible. Left to a state of nature I suspect we would be more the bonobo than the chimpanzee.

That does not mean I don't believe in "nature" rather than "nurture" but there are a whole load more mechanisms for it than just genetic ones. The alleged similarities between the brains of gay men and heterosexual women could just as easily be explained by hormones than genes.

Hormones would even be better regulators of most of the things you've been writing about - more reactive to circumstances (of population etc) than the apparent randomness of a recessive gene striking. Hormones can also change over time and with outside influences - which perhaps explains the fact, we are told, that more than the world's "fair share" of unattached, more altruistic even, men apparently have homoerotic experiences. I myself find that as I get older the delights of women seem to attract me a bit more.

The whole social framework of what sexual expression is valid, and by implication everything else invalid, is buried deep, I believe, in the anglo-saxon protestant psyche. I have a book "English Sexualities" that claims to date the repression of all non-procreative, penetrative, heterosexual, and even, in some places more or less, in one particular position, to around Queen Anne's reign. That there was a particular " germanic" coldness towards any sexual expression other than what was absolutely necessary that came in from northern Europe!

Plus, there are all sorts of issues raised by finding even a gene that could be said to make someone more predisposed to a particular area of the spectrum of sexualities. If an area of that spectrum is deemed unacceptable, or even as not that long ago, an illness, one thing seems sure that mankind will find an argument for eradicating that gene to "prevent" homosexuality.

Anonymous said...

Humans originated in tropical Africa where food is available all year round and hence little foresight or planning is necessary. The main determinant for survival is territorial defence and aggression against other tribes. The mental capacities which are selected by evolution in such an environment are aggression and grabbing what you want when you want it.

However, as tribes moved out of tropical Africa, they entered lands where food supply was seasonal and the climate often hostile. Living in these environments was intellectually challenging and the most intelligent survived. The genes of the tribes who moved out of Africa consequently evolved for greater foresight, forward planning, delayed gratification and greater co-operation and technical organisation - for example in irrigation works and seasonal sowing, harvesting and storage of food in climates with a marked summer/winter or wet/dry season contrasts.

This is the reason for the huge difference in intellectual ability, levels of aggression and civilisation potential between the tropical Africans plus their immediate descendents and all other peoples.

Mark Wadsworth said...

Anon, I have arrived at a similar conclusion.

Maybe we'll end up at the same Re-education Camp?