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← Did Charles Darwin get it wrong?

wice's Avatar Jump to comment 26 by wice

Comment #456269 by crookedshoes

thanks, i already knew that, i just thought that you used it as an example of a real problem for neo-darwinian synthesis (unlike the one mentioned by Peter Forbes at the end of the article, which, i think, is not a real problem).

what i think would be a real problem (it came across my mind when i read your comment about the cavefish) is this: suppose, that e.g. we find a blind species (which is blind because this gene is "switched off"), that had enough time to evolve since the switching off of its ancestor's gene, so it would be extremely unlikely, that the gene didn't change, yet, the gene is intact.

of course, it still wouldn't necessarily discredit natural selection. for example, it could mean, that we don't entirely understand the "switching off" of a gene, so maybe this "switched off" gene is still part of an other gene pathway, and is only "switched off" for that particular pathway, that produces the eyes. i'm not sure whether it's technically possible, but testing several artificially modified versions of the gene in that species could show, that the gene (in its conserved state) is necessary for other functions of the animal.

also, even if testing every possible versions of the gene would show, that it doesn't affect anything else, it would still be possible, that some repair mechanisms make this specific gene very hard to mutate.

Fri, 29 Jan 2010 18:31:00 UTC | #436752