molecular biology

Dear Readers, This post continues directly from Part 2. Second, the authors assume that, in the absence of phenotypic mutations, the first genotypic mutation would be strictly neutral. That is, the selection coefficient for the first mutation is very, very close to zero. It turns out that this is a critical feature. If the first mutation were slightly positive itself (without considering look-ahead) then it could be selected on its own, and the look-ahead effect makes little difference. On the other hand, if the first mutation is slightly negative (including look-ahead), then it will not be positively selected and, again, the effect makes essentially no difference. It is only in a very restricted range of selection coefficients that any significant influence will be Read More ›

Dear Readers, When The Edge of Evolution  The Edge of Evolution: The Search for the Limits of Darwinism  was first published, some Darwinist reviewers sneered that the problem it focused on — the need for multiple mutations to form some protein features (such as binding sites), where intermediate mutations were deleterious — was a chimera. There were no such things, they essentially said. University of Wisconsin geneticist Sean Carroll, reviewing the book for Science, stressed examples where intermediate mutations were beneficial (I never said there weren’t such cases, and discussed several in the book). In the same vein, University of Chicago evolutionary biologist Jerry Coyne assured readers of The New Republic that “[i]n fact, interactions between proteins, like any complex interaction, were certainly built up step Read More ›

This is the first of five posts in which I reply to Professor Ian Musgrave’s “Open Letter to Dr. Michael Behe” on the Panda’s Thumb blog. Musgrave: Dear Dr. Behe I have recently read your response to Abbie Smith’s article on the HIV-1 protein VPU. Ms Smith showed how Vpu’s recently evolved viroporin activity directly contradicts your statement that HIV has evolved no new biding sites since it entered humans (Edge of Evolution, page 143 and figure 7.4, page 144 ). I was greatly disappointed in your response. I must admit to having a special involvement in this case. Firstly, I drew the illustrations for Ms Smith’s article, and its follow up. But secondly, as a member of my professional Read More ›

Dear Readers, Tonight concludes my response to University of Chicago evolutionary biologist Jerry Coyne, which began earlier this week.  As you know if you’ve been following my blog here, Professor Coyne reviewed my new book Edge of Evolution in The New Republic.  I replied to his response here, and he has responded to my reply at TalkReason.org.  Because it quickly gets awkward to include all of the context here, I’m only quoting the portions of his response that I specifically address here.  Readers who want to see the full back-and-forth should read his posted review and response. Coyne: The reviews by Ken Miller in Nature and Sean Carroll in Science cite several examples of the gradual origin of adaptations via the step-by-step accumulation of point mutations in proteins. Behe: Hardly. Read More ›