I agree this doesn’t make sense. If that is indeed Behe’s claim then he seems to be saying that all populations are in continous fitness decline. He could be trying to throw a bone to creationistic ideas like Sanford’s “genetic entropy” or something. I wonder how he squares that with this acceptance of common descent going back almost 4 billion years. Oh wait, God did it of course, silly me!
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More from the Cell paper:
The legend:
Figure 5. The apoB and LYST Protein Sequences
The distribution of fixed nonsynonymous polar bear mutations (blue arrows) compared to the brown bear, using the giant panda sequence as an outgroup. (A) Mutations predicted to affect protein structure based on apoB alignments across 20 vertebrate species, using the SIFT algorithm (Sim et al., 2012), are indicated with hollow circles on arrows. The gray curve shows the cubic smoothing spline of the amino acid conservation scores; higher scores indicate higher conservation across 20 vertebrate species. The x axis shows the amino acid position from the N-terminal, the five domains are based on the human apoB sequence (Prassl and Laggner, 2009).
(B) The same representation as in (A), but for the LYST protein sequence. The domains are based on InterPro.
(C) Mapping of polar bear-specific substitutions and Chediak-Higashi syndrome
causing variants on the protein structure of LYST N-terminal domain.
Note the natures of the various missense mutations, their predicted effects, and other details. Compare with Behe’s assertions.
Maybe Behe elaborates more on these things later in the book (@NLENTS, any chance that you might weigh in?) . But for now, I would say that Ch. 1 is a pretty poor effort.
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In context, the answer was not in fact genetic drift. Sorry. The answer was that the alleles were not less fit.
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Not actually true. The ratio between population size and selection coefficient is important, and below a certain ratio, deleterious alleles have the same fixation probability as neutral alleles. But this is still an irrelevant digression.
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He does not revisit the polar bears, except to make reference to the point he (thinks he) made. @Art - thanks so much for this and, if it’s okay with you, I will quote you in one of the articles I’m writing about this book. I already did name you and quote your Panda’s Thumb article on tURF-13 in my essay for Skeptic. 
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His position is a little more nuanced (but no less coherent) than that. He claims the “devolution” (whatever the hell that means) operates by damaging proteins and can act to diversify at the level of species and maybe genus, so yes, the whole “accumulation of deleterious mutations” bit. But he then also claims that higher level diversification at the level of family and higher (a “change in kind” as the IDers like to call it) requires an influx of new genetic information (which would then get gradually degraded as the new family settles into genera and species). You’re probably waiting with baited breath to hear what evidence he provides for such a bold claim. After having read all three of his books, I am, too.
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Does Behe call those deleterious mutations? Because a damaged protein can be beneficial in the right environment, and I think, by “devolution” he refers to beneficial loss of function, for example loss of eyes in cave fish. If he thinks beneficial loss of function is deleterious, then he’s exceedingly confused.
You’re quite right and Behe does thread the needle better than I just did. He makes the point, correctly, that reduction in the activity of a gene or protein can actually bring fitness gains, so “deleterious” is the wrong word and that’s my mistake, not his. However, he claims that “breaking things” is all that unguided mutations can ever do and that’s where he ignores all the evidence to the contrary. I still take issue with his use of the word “devolution” because I don’t think it actually makes any sense biologically. Evolution does not mean increasing complexity or gains of function or any of that. It just means change, which can mean simplifying and streamlining just as often as getting more complex (if not more so). There really isn’t an opposite of evolution. “Devolve” may make sense in other contexts, but in biology, I don’t think it does. He could be using it tongue-in-cheek, but he uses it over and over in a very specific way and never indicates that he’s anything but serious. To think of evolution as a march toward progress and perfection, toward ever increasing complexity is to misunderstand it a very fundamental level.
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It does play directly to the beliefs of Creationists who make up the large majority of his target audience. Behe isn’t dumb. He knows where the easy money is and what to say to get his slice of the pie.
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That’s what I thought.
It seems an odd position for Behe to take, since it would require millions or billions of directed mutations for all the adaptations that don’t involve “breaking things”. It used to be that he only required divine (sorry, unknown intelligent) intervention for a few IC systems, probably in the low hundreds. It does play well to creationists who like the idea of a creation cursed since the Fall.
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Oh well. I will look forward to learning of the other instances Behe highlights.
Sounds great. Always happy to help out.
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The way I understand it (he doesn’t cover this in his books), he doesn’t take a hard position on how the designer does this, I’m guessing because there’s no evidence. He allows for the frequent “influx” of all the new genetic information over and over, the ongoing miracles kind of thing. Or, it could all be pre-loaded way back and then unfolds in the fullness of time, the perfect pool shot kind of thing. In his discussion of the lemurs of Madagascar, he specifically allows for the pre-loading idea.
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Genetic Drift - - is about sampling error (each generation “samples” the prior generation) than about the nature of the sample:
“Genetic drift (also known as allelic drift or the Sewall Wright effect )[1] is the change in the frequency of an existing gene variant (allele) in a population due to random sampling of organisms.[2] The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces. A population’s allele frequency is the fraction of the copies of one gene that share a particular form.[3] Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation.[4] It can also cause initially rare alleles to become much more frequent and even fixed.”
We are all eager to see Behe finally discuss when God stopped guiding mutations… and how you know that God has stopped guiding mutations for animals in a laboratory, or who are under close observation in the natural state!
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Is a perfect pool shot really pre-loading? Seems a deceptive use of the term. He once had another definition of that, such that all the information (actual genes) was present in the genome of the universal common ancestor, just mostly dormant, and sorted out into all the species we see today and activated where needed. I believe it was pointed out that constant intervention would have been required to prevent the decay of all those dormant genes, which may have caused him to junk that idea.
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Devolution doesn’t make sense. It’s a bit like saying that you drive to work and then dedrive home afterwards. If a species is changing in any direction it is evolution (and you could probably throw stabilizing selection in there too).
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I would be interested in this as well.
I have had the same complaint about that phrase. I certainly think this more recent use of the term pre-loaded (the “setting” of the Universe at the moment of creation) makes more sense than the idea that, say, a single cell organism has all the genetic content of future species.
PS
The exact phrase is not so important; as long as we know what is intended by any alternative suggested.
It also has the advantage that there’s no conceivable way to detect it, as operationally it’s indistinguishable from completely natural evolution. It has the disadvantage that it ignores quantum randomness. You can’t make a perfect pool shot if the balls have only a probability distribution of locations and you can’t know both their positions and velocities at the same time.
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It makes perfect sense to a young earth creationist.God created everything in absolute perfection and it all devoved from there.