Irreducible Complexity

I never thought it would happen but, in my estimation, Richard Lenski has acquired a challenger for the title of “Best Experimental Evolutionary Scientist.” Lenski, of course, is the well-known fellow who has been growing E. coli in his lab at Michigan State for 50,000 generations in order to follow its evolutionary progress. His rival is Joseph Thornton of the University of Oregon who, by inferring the sequences of ancient proteins and then constructing (he calls it “resurrecting”) their genes in his lab, is able to characterize the properties of the ancestral proteins and discern how they may have evolved into more modern versions with different properties. I have written appreciatively about both Lenski and Thornton before, whose work indicates Read More ›

An intriguing ‘hypothesis’ paper entitled “How a neutral evolutionary ratchet can build cellular complexity” (1), where the authors speculate about a possible solution to a possible problem, recently appeared in the journal IUBMB Life. It is an expanded version of a short essay called “Irremediable Complexity?” (2) published last year in Science. The authors of the manuscripts include the prominent evolutionary biologist W. Ford Doolittle. The gist of the paper is this. The authors think that over evolutionary time, neutral processes would tend to “complexify” the cell. They call that theoretical process “constructive neutral evolution” (CNE). In an amusing analogy they liken cells in this respect to human institutions: Organisms, like human institutions, will become ever more ”bureaucratic,” in the sense Read More ›

The science writer Carl Zimmer posted an invited replyhttp://tinyurl.com/yhpm3t7 on his blog from Joseph Thornton of the University of Oregon to my recent comments about Thornton’s work. This is the last of four posts addressing it. References appear at the bottom of this post. At the end of his post Thornton waxes wroth. Behe’s argument has no scientific merit.  It is based on a misunderstanding of the fundamental processes of molecular evolution and a failure to appreciate the nature of probability itself.  There is no scientific controversy about whether natural processes can drive the evolution of complex proteins.  The work of my research group should not be misintepreted by those who would like to pretend that there is. Well, now. I’ll Read More ›

The science writer Carl Zimmer posted an invited replyhttp://tinyurl.com/yhpm3t7 on his blog from Joseph Thornton of the University of Oregon to my recent comments about Thornton’s work. This is the second of several posts addressing it. References will appear in the last post. Now to Professor Thornton’s reply. He writes at length but makes just two substantive points: 1) that neutral mutations occur and can serendipitously help a protein evolve some function (“[Behe] ignores the key role of genetic drift in evolution”); and 2) that just because a protein may not be able to evolve a particular function one way does not mean that it, or some other kind of protein, can’t evolve the function another way (“nothing in our results Read More ›

Dear Readers, Recently a paper appeared online in the journal Proceedings of the National Academy of Sciences, entitled “The reducible complexity of a mitochondrial molecular machine” (http://tinyurl.com/mhoh7w). As you might expect, I was very interested in reading what the authors had to say. Unfortunately, as is all too common on this topic, the claims made in the paper far surpassed the data, and distinctions between such basic ideas as “reducible” versus “irreducible” and “Darwinian” versus “non-Darwinian” were pretty much ignored. Since PNASpublishes letters to the editor on its website, I wrote in. Alas, it seems that polite comments by a person whose work is the clear target of the paper are not as welcome as one might suppose from reading the journal’s Read More ›

Dear readers, I’ve just been through the weirdest book-related experience I’ve had since a Canadian university professor with a loaded rat trap chased me around after a talk I gave a dozen years ago, threatening to spring it on me. Last week I got the following email bearing the title “Invitation to Appear on Bloggingheads TV” from a senior editor at that site: ************* Hi, Michael– I’d like to invite you to appear on Bloggingheads.tv, a web site that hosts video dialogues between journalists, bloggers, and scholars. We have a partnership with the New York Times by which they feature excerpts from some of our shows on their site. Past guests include prominent thinkers such as Paul Krugman, Paul Ehrlich, Read More ›

Dear Readers,At the end of his first post squabbling with Discovery Institute’s Casey Luskin, Brown University Professor Kenneth Miller refers to some great new work by UC San Diego Professor and member of the National Academy of Science, Russell Doolittle. Doolittle, of course, has worked on the blood clotting cascade for about fifty years! (I discussed some of his work in Chapter 4 of Darwin’s Black Box.) In a new paper Doolittle and co-workers analyze DNA sequence data from a primitive vertebrate, the lamprey, thinking that it might have a simpler clotting cascade than higher vertebrates. (1) It is difficult work, because the sequences of lamprey proteins — even ones that are indeed homologous to the proteins of other vertebrates — are significantly Read More ›

Dear Readers, Kenneth R. Miller, a professor of biology at Brown University, has written a new book Only a Theory: Evolution and the Battle for America’s Soul, in which he defends Darwinism, attacks intelligent design, and makes a case for theistic evolution (defined as something like “God used Darwinian evolution to make life”). In all this, it’s pretty much a re-run of his previous book published over a decade ago,Finding Darwin’s God: A Scientist’s Search for Common Ground between God and Evolution. So if you read that book, you’ll have a very good idea of what 90% of the new book concerns. For people who think that a mousetrap is not irreducibly complex because parts of it can be used as Read More ›

Dear Readers, An interesting paper has just appeared in the Proceedings of the National Academy of Sciences, “Historical contingency and the evolution of a key innovation in an experimental population of Escherichia coli.” (1) It is the “inaugural article” of Richard Lenski, who was recently elected to the National Academy. Lenski, of course, is well known for conducting the longest, most detailed “lab evolution” experiment in history, growing the bacterium E. coli continuously for about twenty years in his Michigan State lab. For the fast-growing bug, that’s over 40,000 generations! I discuss Lenski’s fascinating work in Chapter 7 of The Edge of Evolution, pointing out that all of the beneficial mutations identified from the studies so far seem to have been degradative ones, where functioning genes are knocked out or Read More ›

This is the fifth of five posts in which I reply to Dr. Ian Musgrave’s “Open Letter to Dr. Michael Behe” on the Panda’s Thumb blog. Finally, Dr. Musgrave objects to my placing viral protein – cellular protein interactions in a separate category from cellular protein-cellular protein interactions. In Chapter 8 of The Edge of Evolution I had written: Another, more important point to note is that I’m considering just cellular proteins binding to other cellular proteins, not to foreign proteins. Foreign proteins injected into a cell by an invading virus or bacterium make up a different category. The foreign proteins of pathogens almost always are intended to cripple a cell in any way possible. Since there are so many more ways Read More ›