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From: dmark@cs.Buffalo.EDU (David Mark)
Newsgroups: comp.ai
Subject: Re: Genetics and IQ
Message-ID: <9159@cs.Buffalo.EDU>
Date: 10 Aug 89 02:07:48 GMT
References: <3229@cadre.dsl.PITTSBURGH.EDU> <4537@uhccux.uhcc.hawaii.edu>
Reply-To: dmark@sunybcs.UUCP (David Mark)
Organization: SUNY/Buffalo Geography
Lines: 31

In article <4537@uhccux.uhcc.hawaii.edu> lee@uhccux.uhcc.hawaii.edu (Greg Lee) writes:
>From article <3229@cadre.dsl.PITTSBURGH.EDU>, by geb@cadre.dsl.PITTSBURGH.EDU (Gordon E. Banks):
>
>" ... If problem X is such a serious problem that its solution promotes
>" survival of the individual, then intelligence will be selected for.
>" Obviously this occurs, otherwise, we'd all still be Chimps, no?  Why do you
>" think we became intelligent in the first place?
>
>A uniformitarian argument:  intelligence was once selected for,
>therefore it is the presumption that it is now being selected for.  Ok.

Greg, I thought you were going to point out that intelligence may have
been selected for directly up until, say 50,000 years ago, but has not been
selected for since our culture became sufficiently complex.  The third
possibility is:

>But what if special intelligence never was selected for?  It may have
>been manual dexterity that was the advantage, and intelligence got a
>free ride on the extra control mechanisms needed for dexterity.  

There is a very strong inverse correlation between mean number of children
per family and mean family income.  This is certainly the case in the US and 
Canada, and I imagine pretty much the rule in the "developed" countries at
least.  So, we can say that human poverty is being very strongly selected
for at present.  :-)  And, since there is probably at least a mild positive
correlation between intellectual ability and income, that means there
probably is currently selective pressure on human intelligence in the
DOWNWARD direction.   :-) * 2

David Mark
dmark@cs.buffalo.edu