Tuesday 15 May 2012

Demographic change just IS natural selection in action

*

When discussing examples of natural selection which are empirically observable within human experience,

http://charltonteaching.blogspot.co.uk/2012/03/evolutionary-philosophy-versus-specific.html

...I forgot to mention one very relevant example: global demographic change.

*

It is a neglected fact that global demographic change, which has been extremely rapid for the past couple of hundred years, and is apparently accelerating, is simply natural selection in action.

That is, demographic change just is (nearly always) a matter of differential change between populations with heritable differences, significantly due to these heritable differences.

*

All that is required for natural selection to be operating is some causal relationship between the heritable differences and the demographic change, and Bingo! that is the process of natural selection; algorithmic, doing its stuff.

And there has been a heck of a lot of this going-on within living memory.

For instance, European populations have gone from about a quarter of the people in the world to less than half of this.

What's more, of the now existing European population, more than half the women are too old to bear children; so there is a lot more natural selection yet in store.

*

Is there a causal relationship? Yes of course there is. The differential population changes in the human gene pool are (mostly) due to differential fertility; and fertility is causally related to IQ and personality amongst other heritable attributes; and IQ and personality differ both within- and between- populations. 

*

How come this very obvious fact is missed? Missed despite massive and rapid demographic changes - so massive and rapid that they are visible on a year by year basis to anyone who is awake and in possession of a normal perceptual apparatus?

Well, as usual when obvious facts are missed or mislabeled, the root of the problem is Leftism in its modern form of political correctness.

Demographers (as mainstream academic Leftists) do not believe, exclude a priori, any possibility of different human populations being heritably different in ways that would affect reproductive success.

Demographers regard all humans as interchangeable units - or, more accurately, they regard all human differences as due to culture, hence superficial, hence (in principle, it is assumed) malleable - hence of no significant biological relevance.

Demographers are, as a species, merely economists-with-a-twist, merely number-crunchers, non-biological, blank-slaters: but with the difference that the dependent variable of interest is not 'goods' (such as wealth, productivity, production or whatever) but (in effect) reproductive success.

*

With demographic change as a clear and certain example of natural selection in the world of our own experience, we yet again we see the bizarre fashion in which the dominant Leftist intellectual culture combines a dogmatic belief in the only-indirectly-inferred reality of human macro-evolution (e.g. the evolutionary origin of the human species purely by contingent, historical and local selection pressures operating on undirected genetic variation); combines this relatively speculative knowledge with an implacable hostility to the blatantly obvious and undeniable (to any honest person) reality of adaptive micro-evolution within the human species.

http://charltonteaching.blogspot.co.uk/2012/03/evolutionary-philosophy-versus-specific.html

*

Adaptive evolution within the human species just IS global demographic change (amongst other things).

*

To think of it a different way, the human species, considered as a total gene pool, is different now than it was when I was born: not just bigger, but with significantly different balance of gene frequencies. In principle, such change might be due to random drift or natural selection. A few moments thought will reveal that it was the latter - some alleles have increased in frequency, and others decreased, (substantially) because of their impact upon reproductive success.

*

No comments: