Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!ginosko!uunet!mcvax!ukc!etive!epistemi!edai!cam From: cam@edai.ed.ac.uk (Chris Malcolm cam@uk.ac.ed.edai 031 667 1011 x2550) Newsgroups: comp.ai Subject: Re: Inheritance of IQ Message-ID: <470@edai.ed.ac.uk> Date: 19 Jul 89 11:52:40 GMT References: <5453@pt.cs.cmu.edu> <2061@cbnewsh.ATT.COM> <5480@pt.cs.cmu.edu> <458@edai.ed.ac.uk> <602@visdc.UUCP> Reply-To: cam@edai (Chris Malcolm) Organization: University of Edinburgh, Edinburgh Lines: 38 In article <602@visdc.UUCP> jiii@visdc.UUCP (John E Van Deusen III) writes: >In article <458@edai.ed.ac.uk> cam@edai (Chris Malcolm) writes: >> >> On the face of it, suggesting that Chinese and Anglo-Saxons inherit >> exactly the same quality and type of brains (for example) seems as >> silly as suggesting that they inherit exactly the same physique, skin, >> and digestions. > >While it is fairly clear that natural selection could tend to favor >darker skin in equatorial latitudes, intelligence would seem to be >an advantageous survival characteristic under almost any set of >circumstances. There is only one species of Homo sapiens, and the >genetic differences between races are really minuscule. If intelligence was always adavantageous, then there wouldn't be so many successful stupid animals around, such as beetles, sharks, and crocodiles. The cost of running a human brain is pretty severe - I seem to remember about 20% of the average energy expenditure. The point, however, is not simply whether intelligence is or is not in general advantageous, but just _how_ advantageous it was in the various different evolutionary histories through which the various races have passed, and which have produced the obvious differences, such as skin colour (a sunlight adaptation), or different proportions of musle/tendon lengths in the legs (running adaptations), or alcohol detoxification systems (an adaptation to boozing), etc.. I'd be surprised, for example, if these different histories hadn't produced differences in eyesight, smell, and of course, intelligence; and not just in their average values, but in the shape of the distribution curve. It does seem clear that the differences in intelligence between races are dwarfed by the range of individual variation, and the variation due to environmental variation, but I don't think we have good enough data yet, or even the measuring tools, to say that it is minuscule. -- Chris Malcolm cam@uk.ac.ed.edai 031 667 1011 x2550 Department of Artificial Intelligence, Edinburgh University 5 Forrest Hill, Edinburgh, EH1 2QL, UK