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Darwin-L Message Log 8:98 (April 1994)
Academic Discussion on the History and Theory of the Historical Sciences
This is one message from the Archives of Darwin-L (1993–1997), a professional discussion group on the history and theory of the historical sciences.
Note: Additional publications on evolution and the historical sciences by the Darwin-L list owner are available on SSRN.
<8:98>From BENEDICT@VAX.CS.HSCSYR.EDU Wed Apr 27 10:03:56 1994 Date: Wed, 27 Apr 1994 10:59:54 -0500 (EST) From: BENEDICT@VAX.CS.HSCSYR.EDU Subject: Re: Vitamin C To: darwin-l@ukanaix.cc.ukans.edu I think the explanation of why primates might have lost the ability to synthesize vitamen C is a bit backwords. Regardless of cost, if they are getting sufficient vitamen C in their diet, there is no selective pressure to maintain the genes that run that synthetic pathway, and any mutations that destroy it can (but won't necessarily) accumulate. In primates, that's evidently what happened. That being the case, there ought to be "silent genes" (the damaged loci) floating about in primate gene pools. Someone who know what the pathway is probably can tell us what enzymes are disabled in primates as compared to mammals that synthesize vitamen C, and then someone with access to the human gene mapping database can look for those loci and see what's happened to them. Note that this explanation requires no selection. It's just something that happens, but it happens because there is no selection on the loci in question. Paul DeBenedictis SUNY Health Science Center at Syracuse
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