Limits of Evolution

Dear Readers, An interesting paper appeared several months ago in an issue of the journal Genetics, “Waiting for Two Mutations: With Applications to Regulatory Sequence Evolution and the Limits of Darwinian Evolution” (Durrett, R & Schmidt, D. 2008. Genetics 180: 1501-1509). This is the fifth of five posts that discusses it. Cited references appear in this post. The final conceptual error that Durrett and Schmidt commit is the gratuitous multiplication of probabilistic resources. In their original paper they calculated that the appearance of a particular double mutation in humans would have an expected time of appearance of 216 million years, if one were considering a one kilobase region of the genome. Since the evolution of humans from other primates took much less time Read More ›

An interesting paper appeared several months ago in an issue of the journal Genetics, “Waiting for Two Mutations: With Applications to Regulatory Sequence Evolution and the Limits of Darwinian Evolution” (Durrett, R & Schmidt, D. 2008. Genetics 180: 1501-1509). This is the fourth of five posts that discusses it. Cited references will appear in the last post.  Now I’d like to turn to a couple of other points in Durrett and Schmidt’s reply which aren’t mistakes with their model, but which do reflect conceptual errors. As I quote in a previous post, they state in their reply, “This conclusion is simply wrong since it assumes that there is only one individual in the population with the first mutation.” I have shown previously that, Read More ›

Dear Readers, An interesting paper appeared several months ago in an issue of the journal Genetics, “Waiting for Two Mutations: With Applications to Regulatory Sequence Evolution and the Limits of Darwinian Evolution” (Durrett, R & Schmidt, D. 2008. Genetics 180: 1501-1509). This is the third of five posts that discusses it. Cited references will appear in the last post. The third problem also concerns the biology of the system. I’m at a bit of a loss here, because the problem is not hard to see, and yet in their reply they stoutly deny the mistake. In fact, they confidently assert it is I who am mistaken. I had written in my letter, ‘‘… their model is incomplete on its own terms because it Read More ›

Dear Readers,  An interesting paper appeared several months ago in an issue of the journal Genetics, “Waiting for Two Mutations: With Applications to Regulatory Sequence Evolution and the Limits of Darwinian Evolution” (Durrett, R & Schmidt, D. 2008. Genetics 180: 1501-1509). This is the second of five posts that discusses it. Cited references will appear in the last post.  Interesting as it is, there are some pretty serious problems in the way they applied their model to my arguments, some of which they owned up to in their reply, and some of which they didn’t. When the problems are fixed, however, the resulting number is remarkably close to the empirical value of 1 in 10^20. I will go through the difficulties in turn. Read More ›

Dear Readers,  An interesting paper appeared several months ago in an issue of the journal Genetics, “Waiting for Two Mutations: With Applications to Regulatory Sequence Evolution and the Limits of Darwinian Evolution” (Durrett, R & Schmidt, D. 2008. Genetics 180: 1501-1509). This is the first of five posts that discusses it. Cited references will appear in the last post.  As the title implies, it concerns the time one would have to wait for Darwinian processes to produce some helpful biological feature (here, regulatory sequences in DNA) if two mutations are required instead of just one. It is a theoretical paper, which uses models, math, and computer simulations to reach conclusions, rather than empirical data from field or lab experiments, as The Edge does. The authors Read More ›

Dear Readers, In a long book review in The New Republic, University of Chicago evolutionary biologist Jerry Coyne calls Brown University cell biologist Ken Miller a creationist. No surprise there — “creationist” has a lot of negative emotional resonance in many intellectual circles, so it makes a fellow’s rhetorical task a lot easier if he can tag his intellectual opponent with the label. (Kind of like calling someone a “communist” back in the 1950s.) No need for the hapless “creationist” to be a Biblical literalist, or to believe in a young earth, or to be politically or socially conservative, or have any other attribute the general public thinks of when they hear the “C” word. For Coyne, one just has to think that Read More ›

Dear Readers, An interesting paper appeared recently in the New England Journal of Medicine. (1) The workers there discovered some new mutations which confer some resistance to malaria on human blood cells in the lab. (Their usefulness in nature has not yet been nailed down.) The relevance to my analysis in The Edge of Evolution is that, like other mutations that help with malaria, these mutations, too, are ones which degrade the function of a normally very useful protein, called pyruvate kinase. As the workers note: “[H]eterozygosity for partial or complete loss-of-function alleles . . . may have little negative effect on overall fitness (including transmission of mutant alleles), while providing a modest but significant protective effect against malaria. Although speculative, this situation Read More ›

Dear Readers, California State University emeritus Professor Mark Perakh (author of Unintelligent Design) and I recently taped an episode of the program “Voice of Reason”,http://www.cn8.tv/channel/article.asp?lArticleID=5 195&lChannelID=603 with the venerable Philadelphia newsman Larry Kane. We discussed intelligent design, The Edge of Evolution, and other topics for thirty minutes. The show will air Sunday March 2nd at 9:30 p.m. on CN8, the Comcast Network.

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, Usually I use this space to address reviews of The Edge of Evolution that have appeared in print in journals, newspapers, or magazines. The reason is that usually print media recruit leading figures in evolutionary biology to write a review, and so those reviews represent the thoughts of some of the best minds in the field. Examining their thoughts, then, can quickly give us a good understanding of whether there are ready answers to the challenges and arguments posed by The Edge. After all, if reviews by the likes of Richard Dawkins or Jerry Coyne fail to engage the arguments of the book, and instead rely mainly on bluster and non sequiturs, then that’s solid evidence that no good replies exist. Read More ›