Edge of Evolution
Michael Behe's new book "Edge of Evolution" is out and a review in the journal Science has been written by Sean Carrol. DaveScot at uncommondescent has started a thread to fisk this review (making it a rebuttal of a rebuttal, in essence).
From the review:
DaveScot fisks:Here’s one glaring mistake in the author’s review (my emphasis):
In Darwin’s Black Box, he posited that genes for modern complex biochemical systems, such as blood clotting, might have been “designed billions of years ago and have been passed down to the present but not ‘turned on’”. This is known to be genetically impossible because genes that aren’t used will degenerate, but there it was in print.
It’s easily possible. Error checking to insure data integrity to any arbitrary reliability standard is de rigueur in computer memory systems. In my experience most things that human designers have come up with in electronic information processing has antecedents in biological information systems. I therefore anticipate things we’ve invented on our own to have parallels in organic systems and mechanisms for insuring any required level of data integrity is no exception.
Neither DaveScot nor Carrol is really right here. While it is not easily possible, it is neither impossible. Carrol should really have said that there is no evidence that unused genetic information will be retained over long time spans . The interesting bit here is that Carrol has made made the sort of argument that IDers commonly (and usually excusively) make - a negative one. IDers tend to claim that evolution can't do this and that. Even though DaveScot thinks there is evidence lacking that natural processes can account for the diversity of life we see today, he has no problem appealing to processes that there is no evidence for. Interesting... His appeal to error checking the way humans do it is interesting as well, given that in living organisms, "the error checking mechanisms" could change as well. And if they do, then unused genetic information would presumably change with it.
Like DaveScot, I have an anticipation as well: whenever there is any sort of parallell between living beings and humanly designed things, IDers will claim that this is evidence for ID.
2 Comments:
Sean Carroll: "This is known to be genetically impossible because genes that aren’t used will degenerate..."
Genetic mutations occur in genes that are used and in genes that are not used. Natural selection operates only on the genes that are used. In genes that are not used, there is no corresponding phenotype, thus there is nothing which selects them out.
Unless there are other mechanisms for retaining genetic material. I don't know how this would be done. One could, perhaps, picture a system whereby a cell dies whenever it looses one of two interdependent genes. Something akin to a postsegregational killing (PSK) system springs to mind as a possibility (PSK systems typically consist of the products of two genes usually termed toxin and antidote). In such a system, the only phenotype displayed by the genes is their ability to kill the host when they disappear.
IF IDers would want to resort to such a system, they of course have to explain why current genes don't appear to work in such a manner. But then IDers are free to add ad hoc after ad hoc into infinity.
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