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 letters-policy announcement (“We wish to provide readers with an opportunity to constructively address a difference of opinion with authors of recent papers. Readers are encouraged to point out potential flaws or discrepancies or to comment on exceptional studies published in the journal. Replication and refutation are cornerstones of scientific progress, and we welcome your comments.”) (http://tinyurl.com/mpf4sp) My letter received a brusque rejection. Below I reproduce the letter for anyone interested in my reaction to the paper. (By the way, it’s not just me. Other scientists whose work is targeted sometimes get the run around on letters to the editor, too. For an amusing / astounding example, see http://tinyurl.com/n5dbdz.) Call me paranoid, but it seems to me that some top-notch journals are real anxious to be rid of the idea of irreducible complexity. Recall that last year Genetics published a paper purportedly refuting the difficulty of getting multiple required mutations by showing it’s quick and easy in a computer—if one of the mutations is neutral (rather than harmful) and first spreads in the population (http://tinyurl.com/mxjwdy). Not long before that, PNAS published a paper supposedly refuting irreducible complexity by postulating that the entire flagellum could evolve from a single remarkable prodigy-gene (http://tinyurl.com/l6kjh4). Not long before that, Science published a paper allegedly refuting irreducible complexity by showing that if an investigator altered a couple amino acid residues in a steroid hormone receptor, the receptor would bind steroids more weakly than the unmutated form (http://tinyurl.com/kjq4e4 and http://tinyurl.com/lqav6p). (That one also made the New York Times!) (http://tinyurl.com/q6w3qq) For my responses, see here (http://tinyurl.com/meeqfs), here (http://tinyurl.com/3vzxet), here (http://tinyurl.com/ln7a6k), and here (http://www.discovery.org/a/3415). So, arguably picayune, question-begging, and just plain wrong results disputing IC find their way into front-line journals with surprising frequency. Meanwhile, in actual laboratory evolution experiments, genes are broken right and left as bacteria try to outgrow each other (http://tinyurl.com/lxvge5). Well, at least it’s nice to know that my work gives some authors a hook on which to hang results that otherwise would be publishable only in journals with impact factors of -3 or less. But if these are the best “refutations” that leading journals such as PNAS and Science can produce in more than a decade, then the concept of irreducible complexity is in very fine shape indeed. ************* To the editor: Reducible versus irreducible systems and Darwinian versus non-Darwinian processes The recent paper by Clements et al (1) illustrates the need for more care to avoid non sequiturs in evolutionary narratives. The authors intend to show that Darwinian processes can account for a reducibly complex molecular machine. Yet, even if successful, that would not show that such processes could account for irreducibly complex machines, which Clements et al (1) cite as the chief difficulty for Darwinism raised by intelligent design proponents like myself. Irreducibly complex molecular systems, such as the bacterial flagellum or intracellular transport system, plainly cannot sustain their primary function if a critical mechanical part is removed. (2-4) Like a mousetrap without a spring, they would be broken. Here the authors first postulate (they do not demonstrate) an amino acid transporter that fortuitously also transports proteins inefficiently. (1) They subsequently attempt to show how the efficiency might be improved. A scenario for increasing the efficiency of a pre-existing, reducible function, however, says little about developing a novel, irreducible function. Even as evidence for the applicability of Darwinian processes just to reducibly complex molecular machines, the data are greatly overinterpreted. A Darwinian pathway is not merely one that proceeds by “numerous, successive, slight modifications” (1) but, crucially, one where mutations are random with respect to any goal, including the future development of the organism. If some mutations arise non-randomly, the process is simply not Darwinian. Yet the authors say nothing about random mutation. Their chief data are sequence similarities between bacterial and mitochondrial proteins. However, the presumably homologous proteins have different functions, and bind non-homologous proteins. What is the likelihood that, say, a Tim44-like precursor would forsake its complex of bacterial proteins to join a complex of other proteins? Is such an event reasonably likely or prohibitively improbable? Clements et al (1) do not provide even crude estimates, let alone rigorous calculations or experiments, and thus provide no support for a formally Darwinian process. Their only relevant data in this regard is their demonstration that a singly-mutated bacterial TimB can substitute for Tim14 in mitochondrial transport. While that is certainly an interesting result, rescuing a pre-existing, functioning system in the laboratory is not at all the same thing as building a novel system step-by-random-step in nature. Biologists have long been wary of attempts to fill in our lack of knowledge of the history of life with imaginative reconstructions that go far beyond the evidence. As I have discussed (5), extensive laboratory evolution studies over decades offer little support for the plausibility of such felicitous scenarios as Clements et al (1) propose. The authors may well be overlooking formidable difficulties that nature itself would encounter. References

1. Clements A, et al. (2009) The reducible complexity of a mitochondrial molecular machine. Proc Natl Acad Sci USA doi/10.1073/pnas.0908264106.
2. Behe, MJ (1996) Darwin’s Black Box :The Biochemical Challenge to Evolution (Free Press, New York).
3. Behe MJ (2000) Self-organization and irreducibly complex systems: A reply to Shanks and Joplin. Phil Sci 67:155-162.
4. Behe MJ (2001) Reply to my critics: A response to reviews of Darwin’s Black Box: the biochemical challenge to evolution. Biol Phil 16:685-709.
5. Behe, MJ (2007) The Edge of Evolution: the Search for the Limits of Darwinism (Free Press, New York).

*************

The editor-in-chief of Bloggingheads TV, Robert Wright, has re-instated my interview with linguist John McWhorter (http://bloggingheads.tv/diavlogs/22075) on that website. Wright was away last week when the brouhaha occurred, and it’s good to see that a steady editorial hand is back in charge.

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, Frans de Waal, David Frum, Richard Wrangham, Francis Fukuyama, Robert Kagan, and Michael Kinsley.

Here is one of our recent shows, a dialogue between Paul Nelson, of the Discovery Institute, and Ron Numbers, of Wisconsin-Madison:

http://bloggingheads.tv/diavlogs/21107

I’m hoping that you might be interested in participating, as well.  First-time participants often report how refreshingly unconstrained they find the format—how it lets them present their views with a depth and subtlety not possible on TV or radio. We’d love to have you join us.

If you’re available, please let me know, and we can see about arranging a taping. Thank you for your time.

**************

He seemed like such a nice fellow, so after a couple days I emailed him back to say, sure, I’d be glad to. The editor responded, okay, sometime next week, your discussion partner will be John McWhorter of the Manhattan Institute. I had never heard of McWhorter before, so googled his name, and saw that he’s a linguist who often writes on race matters. I didn’t know what to expect because I know some conservatives (which he seemed to be from his bio) don’t like ID one bit.

Everything was arranged for the taping Tuesday afternoon. When the interview started, I was surprised and delighted to learn that McWhorter was actually a fan of mine. He said (I’m paraphrasing here) he loved The Edge of Evolution and wanted the book to become better known. He said that this was one of the few times that he initiated an interview at Bloggingheads. He said he was familiar with criticisms of the book and found them unpersuasive. He said that Darwinism just didn’t seem to him to be able to cut the mustard in explaining life, and he had yet to read a good, detailed explanation for a large evolutionary change. He also said that he had never believed in God, but that EOE got him thinking. In return I summarized my arguments from EOE, talked about protein structure, addressed his objections that intelligent design is “boring” and a scientific dead-end, and so on. At the end of the taping I thought, gee, those folks at Bloggingheads TV are a real nice bunch.

The next day I emailed the Bloggingheads editor to ask when the show would go on. He answered right back that at that very moment it had been activated, and thanks for participating. I clicked the link, and there was the show. I thought I looked older on screen than I am (my beard isn’t really that white), but emailed some friends to let them know the interview was up anyway. That evening I got an email from one of them saying that he couldn’t find the interview — it had been yanked.

Let me emphasize this, dear readers. Here we are living in the land of the free and the home of the brave. And yet a web site puts up an interview with an (ahem…) somewhat controversial figure, pulls it back down within hours, erases it, sends it down the memory hole. Why might that be? There would seem to be two possibilities: 1) maybe we aren’t quite as free as we think, or 2) maybe not quite as brave.

I bet on possibility #2. Because of the magic of the internet, it turns out that shortly after the show’s posting the comments section of the site was overrun by “bitterly virulent” (in the words of one principal in this saga) cyber bullies, some murmuring darkly about a grim future for Bloggingheads. After I found out the video was removed I emailed John McWhorter and the editor to ask for an explanation, and John emailed back that he himself requested the video to be pulled because people thought he was too easy on me, which was supposedly contrary to that old Bloggingheads spirit. I find that quite implausible (other shows on the site feature discussions between people who agree on many things). Rather, I suspect the folks at the website weren’t expecting the vitriolic reaction, began to worry about their good names and future employment prospects, pictured themselves banished to a virtual leper colony, panicked, and folded.

Well, mobs, including internet mobs, are scary things, and it’s understandable to panic when they unexpectedly show up at your door. But if you’re going to set up a website to air discussions about contentious issues of the day, you should have a whole lot more guts than displayed by Bloggingheads TV.

For those who want to watch for themselves the interview that made grown men tremble, it can be seen at http://tinyurl.com/lqonmn.

Below is a time-lapse picture of my Bloggingheads interview. I’m the guy on the right.

To the editor:

 In his article “On the Origin of the Immune System” (Science, May 1, 2009) John Travis makes the same mistake as did the judge in the 2005 Dover trial — badly confusing the notions of intelligent design, common descent, and evolution. Citing the courtroom theatrics of the lawyers who piled a stack of textbooks and articles in front of me, Travis quotes me as remarking “They’re wonderful articles. … They simply just don’t address the question I pose.” Unfortunately, Travis seems uninterested in what that question might be. Instead he cheers, “Score one for evolution.”

 Although some news reporters, lawyers, and parents are confused on the topic, “intelligent design” is not the opposite of “evolution.” As some biologists before Darwin theorized, organisms might have descended with modification and be related by common descent, but the process might have been guided by some form of intelligence or teleological driving force in nature. Darwin’s chief contribution was not the simple idea of common descent, but the hypothesis that evolution is driven completely by ateleological mechanisms, prominently including random variation and natural selection. Intelligent design has no proper argument with the bare idea of common descent; rather, it disputes the sufficiency of ateleological mechanisms to explain all facets of biology. Those who fail to grasp such distinctions are like people who can’t distinguish between the ideas of Darwin and, say, Lamarck.

 In the courtroom scenario Travis recounts, I was testifying that science has not shown that a Darwinian mechanism could account for the immune system. Travis’s article itself confirms that is still true. He cites some biologists who think the adaptive immune system arose in a “big bang”; he quotes other scientists who assert, “There was never a big bang of immunology.” He discusses vertebrate immunologists who think they know what the selective advantage of the system is; he quotes invertebrate immunologists who feel otherwise. So are we to think that its history is uncertain and even its selective advantage is unknown, yet the mechanism by which the adaptive immune system arose is settled?

In my court testimony I cited the then-new article by Klein and Nikolaidis, “The descent of the antibody-based immune system by gradual evolution” (Proc. Natl. Acad. Sci. USA 102:169-174, 2005), which first disputed the big bang hypothesis. In it the authors candidly remark, “Here, we sketch out some of the changes that the emergence of the AIS entailed and speculate how they may have come about.” Valuable as it might be to science, however, speculation is not data, let alone an experimental result. Students are poorly served when they are not taught to distinguish among them.

Michael J. Behe

To the editor:

In their recent article “Bacterial flagellar diversity and evolution: seek simplicity and distrust it?” Snyder et al. (2009) [1] attribute to me a view of irreducible complexity concerning the flagellum that I do not hold. They write “One advocate of ID, Behe, has argued that the bacterial flagellum shows the property of ‘irreducible complexity’, that is, that it cannot function if even a single one of its components is missing”. That isn’t quite right. Rather, I argued that necessary structural and functional components cannot be missing. In Darwin’s Black Box I wrote, “The bacterial flagellum uses a paddling mechanism. Therefore it must meet the same requirements as other such swimming systems. Because the bacterial flagellum is necessarily composed of at least three parts—a paddle, a rotor, and a motor—it is irreducibly complex.” [2] A particular auxiliary component of the flagellar system, such as, say, a chaperone protein, may or may not be needed for the system to work under particular circumstances. However, if it is missing a necessary mechanical part, it simply cannot work.

That shouldn’t be controversial. In fact Snyder et al (2009) avail themselves of the same reasoning when they write about a hook-basal-body complex recently discovered in Buchnera aphidicola, which “lacks … the gene for flagellin”. [1] They conclude it “must have some role other than motility.” Well, why must it have some role other than motility? Because, of course, it is missing the paddle, and therefore can’t work as a paddling propulsion system. In other words, in my sense of the term, it is irreducibly complex.

Snyder et al (2009) think Buchnera’s derived structure “illuminates flagellar evolution by providing an example of what a simpler precursor of today’s flagellum might have looked like – a precursor dedicated solely to protein export rather than motility”. [1] I think that simplicity should be distrusted. The activity of a protein export system has no obvious connection to the activity of a rotary motor propulsion system. Thus the difficulty of accounting for the propulsive function of the flagellum and its irreducible complexity remains unaddressed. In regard to the flagellum’s evolution, Snyder et al’s (2009) advice to distrust simplicity is sound and should be followed consistently. [1]

Michael J. Behe

Professor of Biological Sciences

Lehigh University

Bethlehem, PA 18015

References

1. Snyder, L.A., Loman, N.J., Futterer, K., and Pallen, M.J. (2009) Bacterial flagellar diversity and evolution: seek simplicity and distrust it?  Trends Microbiol. 17, 1-5.

2. Behe, M.J. (1996) Darwin’s Black Box: the Biochemical Challenge to Evolution. The Free Press, New York, p. 72.