> And I think Eric's version of the same argument doesn't even
> work in its own terms; what possible instincts might an Iron Age man have
> developed that would encourage him to reduce the size of his family when
> his access to food increased?
>
What? Remind me - where did I write or infer something like this?
You're correct to complain about my first posts. But I still think you're missing something. For a hint, I refer you to my post about adaptive / maladaptive behaviour. It's not worked out fully but I guess it is here that you're going wrong.
I'll come clean - I like this thread because it's getting me to think on my feet. I have to examine things I accept as true very carefully in order to attempt to explain them coherently (not always successful, this, but still).
So let me ask- what, exactly, is it you understand Neo-Darwinism, or sociobiology (different things, you pick the ground you want to fight on) to be saying that is refuted by the demographic shift? If we sort this out, things should be easy.
To get ahead of myself here, you said in your original post:
> 2) Is this not [i.e. the shift] a very severe problem for most sociobiological theories, or
> > for any theories which rely on "the desire to propagate genes" as being a
> > major determinant of human behaviour? At the very least, it is an anomaly
> > to be explained away, that those members of society who might be thought
> to
> > be best placed to have large families, tend not to.
>
There's one problem for a start. Sociobiology does not claim the desire to propagate genes is a major determinant of human behaviour. Sociobiology in fact explicitly concedes the overwhelming dominance of cultural factors in human behaviour. And considered in the proper language, NOTHING 'desires to propagate genes' ... rather it is that genes that are most effective at copying themselves (nowadays through their phenotypic effects, i.e. the bodies they're contained within) will spread through a population (by definition - they're the most effective at copying themselves, they'll be more of them). But there isn't any law that says genes MUST be effective at copying themselves (only that, by definition, genes that do so will be prevalent). For example, a mutation may give rise to a gene that kills off its bearer before breeding age (I'll leave out the complications involved in actual transmission, e.g. whether it's dominant / recessive, etc). That gene will pass out of the population very quickly. Is this an 'anomoly' because things are 'trying to perpetuate their genes'? No. Not if you take out the misleading popular science intentionality stuff.
In the same way, a maladaptive CULTURAL (not genetic) feature would have similar effects - but that doesn't make the theory wrong (Wilson says something about maladaptive cultural features in humans - specifically that they can last a long time because humans are ecologically dominant and thus not quickly brought low by their mistakes - I'll see if I can find it later).
Anyway I'm starting to get repetitive - but can you see what I'm getting at here? Can you see why your question is fundamentally misconceived?
Thanks.
Eric