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Results for behe cassone:
Rod Nibbe, a commenter at In the Pipeline has a blog for his Airedale, Rufus, who sometimes channels his master. Rufus, (or Rod) has blogged on the Kitzmiller ruling, and raises a some interesting points on the ID side. I've blogged before that defenders of the neo-Darwinian synthesis should be wary of the trap of trying to disprove ID. If you believe, as I do, that ID is not falsifiable, then trying to falsify it based on evidence is a fools errand. So rushing in where angels dare to tread...I'm going to try to engage (not disprove) some of the points out there, including Rufus'. I should start by pointing out that Rod presents his arguments at In the Pipeline as playing the Devil's advocate, and I don't know where he actually stands on the intellectual merit of ID. Rufus: ID probably shouldn't be taught in a science curriculum [typo fixed], agreed, but the significant weaknesses of the evolutionary hypothesis ought to be.What weaknesses he's referring to are not outlined or linked in that post. The specified complexity and irreducible complexity arguments strike me as unconvincing, even though I'm not sure that I agree with all of the critiques...but that's for other posts (See here for my take on irreducible complexity, and why the "No they're not IC" argument is misguided). Rufus: Astronomers continue to stress how large and old the universe is; it doesn't strike me as too unlikely that 1) intelligent life is out there, and 2) that it's been mucking around with DNA A LOT longer than humans have. Taken in that light, life on this planet is the result of a progressively more complicated lab experiment. "Wait!" neo-Darwinists shout, "then how do you account for the observed homology in proteins!" Simple, re-use of design. Sound familiar programmers?An aside: There's a minor trap here, that Rod should beware of, in case he runs into other nitpicky profs like me. Homology in biology contexts is the property of being derived from a common ancestor by definition (at least it's supposed to be. Lots of biologists misuse the term). At the molecular level studied by Pearson (the linked researcher), sequence and structural similarity is taken as evidence for homology. Rufus: It also went unmentioned during this brouhaha that Intelligent Design need not mean Optimal Design .The reuse and nonoptimality arguments relate to inferences about the nature of the Designer and the design process. Note that this is not the same as the question of whether knowledge of the nature of the designer is needed to infer design in the first place. Since that ID per se is not falsifiable, we can do the thought experiment of asking what we would ask next if we buy the Design inference. For example, we can ask whether reality as we know it constrains the properties of any design process/Designer that could be invoked as responsible for terrestrial life. Reuse of modules and standardized parts is indeed a feature of designed artefacts, from wagons with standard axle lengths to computer programs using modular code. Nature almost always uses different versions of a module in different organisms; the sequences of proteins with the same biochemical function are different. Actually, there are differences within species, but the differences among species are greater. Some differences in which version of a module is used could be attributed to function, but other differences, such as the mutations in the DNA that don't change the protein sequence are almost certainly neutral. How would we expect different kinds of designers to choose modules? In particular, why would a Designer build, much less use, functionally equivalent versions of the same thing? I can imagine that design might include these differences to mark the DNA of different species, out of pure whimsy, or to experiment with what mutations are actually neutral. But none of those explanations is sufficient to explain the observation that the pattern of differences is consistent with descent with modification from a series of common ancestors. This has been seen so many times that if it is a designed feature of separate creation, then it is hard to see a purpose other than to lay a false trail leading to common descent. There is a lot of debate on the web about what constitutes a nonoptimal design. In the Behe-Cassone debate here at TAMU, Behe made this argument in favor of the inverted design of the vertebrate eye, which is one of the popular examples. I find this unconvincing, for reasons that I might blog later. But here's a different kind of evidence for nonoptimal design. There are many examples of invasive species outcompeting native organisms. In head to head competition, the winning species is by definition better optimized to the environment, whether by evolution or design. As I understand it, the ID site linked by Rufus is arguing that even if we accept these examples, nonoptimal design does not preclude the design inference per se. I agree. It's not falsifiable, remember. But, like the reuse issue, accepting these data places constraints on the hypothetical design process. The generic version of ID argues for separate creation of species, but does not dispute that these creations occurred over a very long time. Either the designer was not aware of the optimal design at the time a species was created, or the designer knew that a nonoptimal design was being used. The first option is inconsistent with an omnipotent designer along the lines of the usual view of God. But that's OK, since ID does not require omnipotence...the designer could be capable of learning from experience. But there's still a problem. At any given interval of geological time, new species would have been created in different genera across different domains and phyla. In human designs, innovations tend to spread across kinds of designed objects by reuse and imitation...there are bigger differences in technology across time than across kinds. Consider the appearance of bronze, iron, steel, aluminum, plastics, carbon composites in different kinds of objects. When more efficient code modules appear for a particular software task, they get incorporated across different kinds of applications that are not related by descent. In biology we see the opposite pattern. As with reuse, the family tree is a better predictor of what nonoptimal forms are found than the creation date. Undoubtedly, the design choices could reflect any number of factors that are not apparent to human intelligence. But while we may not understand those choices, we can ask whether it seems likely that the choices would leave a chain of evidence that matches descent with modification so well...unless the match to evolutionary theory is a feature, not a bug. A reply to this goes back at least to Dobzhansky However offensive the notion may be to religious feeling and to reason, the anti-evolutionists must again accuse the Creator of cheating. They must insist that He deliberately arranged things exactly as if his method of creation was evolution, intentionally to mislead sincere seekers of truth.Since it does not specify the source of design, this is not a problem for ID, which merely has to adjust to allow designers who lack the bourgeouis morality of the conventional watered-down 20th century benign and merciful Judeo-Christian God that Dobzhansky apparently believed in. ID is compatible with all sorts of other designers, within the constraints discussed above. The subset that require that the designer is deliberately covering the traces of design, include many where the designer is deceiving us about other aspects of reality. Some schemes could be compatible with believing that what we claim from science is not a deception. There could be multiple designers, using different versions to accomodate the intellectual property rules of the Gods, I suppose. Descent with modification would reflect the inability of the makers of vertebrates to use the designs of the makers of cephalopods.
Now for what I've been meaning to blog all weekend... Back on Nov 30, USA Today published an editorial by Cal Thomas and Bob Beckel* with the title: Intelligent design: What do scientists fear?This is a nice example of how when the stupid party and the evil party agree, it's usually on a stupid, evil idea. I had ignored this when PZ Myers asked "Who the heck is Bob Beckel?"...but emails have been circulating now that Case Western's Patricia Princehouse responded by calling for the debate proposed by Beckel and Thomas. Here at TAMU, we've been there, done that. Another debate on ID is described in the Dec 5 New Yorker article on the Dover trial. It's not online, but via Crooked Timber, a Q&A with the author is. Having watched the leadup to the debate here at TAMU, here's my sense of what scientists actually fear about ID...and what we don't fear.
Personally, I think that we biologists have to deal better with our fears. We should talk about ID in communities where it gets in the way of teaching real biology...and we need to stand up for those who will be caught in the resulting political storms when people think that their religion is being attacked (N.b this does not mean we should try to attack people's religions). But that's much easier for me to say as a tenured university professor than it would be for someone with less job security. *Thomas is a noted conservative pundit. Beckel apparently was involved in the Mondale campaign...I've often felt that the strongest evidence for unbalanced coverage on Fox News isn't the folks they put up on the right...it's the lightweights that they put on for the other side, including frequent appearances by Beckel. Unfortunately, it's hard for me to think of the Dem intellectual heavyweights I'd like to see...
Commenting on a Nick Kristof piece that is behind the Times Select wall, Derek Lowe writes: Kristof goes on to talk about the consequences of scientific ignorance, but he makes the kind of mistake one makes after being marinated in the New York Times for years:Commenters argue that in the US, it's only the right that's anti-science, the anti-science folks on the left are an insignificant fringe. I'm with Derek on this one. Seems to me that stupidity crosses party and ideological lines. But then I recently saw the rerun of the Frontline that starts with Tom Harkin pushing alternative quackery onto the NIH...and if you're reading In the Pipeline and agree that pharma does real science, do you think that price controls and opposition to liability caps on pharmaceuticals and vaccines are pro-science, anti-science, or neutral? To be technical, I'm not sure any of these folks is truly anti-science. After all, the dispute with ID, "creation science", megavitamins, HIV denial, vaccine-resisters et al. is about the fact that they either aren't really science or they're bad science...the proponents of all kinds of fringe beliefs want to be taken into the scientific fold. That's not anti-science. That's science envy, and given the success of science in improving the human condition (on balance) it's not surprising. In throwing around the accusation of anti-science, we should be careful to distinguish opposition to science from opposition to things favored by a majority of living scientists. Thus, I would not consider failing to increase the NIH and NSF budgets to be anti-science, even though I'd support more money for both for obvious self-interested reasons. In addition, I don't think opposing the Kyoto accords is anti-science. It may not be based on good science*, but the opposite of good science is bad science, not anti-science. This distinction is needed because there are people out there who I would characterize as genuinely anti-science. There aren't that many...they think it's something we shouldn't be doing at all. The more common form (Luddites) is based on the idea that the negative consequences of Science applied to war and/or pollution/overpopulation outweigh the benefits. To the extent that this is a strain in the US, I think it's more common on the Left...but it goes back to all kinds of "noble savage" mythology. This form is arguably anti-Science only because they're anti-Technology and/or anti-Homo sapiens. The other strain (Post-modernists?) is almost exclusively in academic hothouses, and even there it may be waning. This group sees Science as a social construct tool of oppression that doesn't have special standing in seeking valid knowledge about reality. I thought these were a caricature until seeing one show up at the Darwin v. ID debate. Both sides shouted him down. *The main opposition to Kyoto seems to involve denying either the sign/magnitude of warming, or that it is anthropogenic. But it may be that the scientific position would be to recognize that warming is real, it is almost certainly anthropogenic, and that Kyoto should still be opposed as a symbolic and unimplementable agreement, with side effects. Maybe someday I'll elaborate on this.
Here are some powerpoint files from Vincent Cassone's debate with Michael Behe last week. Cassone Presentation (ppt) (4.6 Mb) Cassone Response Figures (ppt) (2.6 Mb) The second powerpoint includes information about the Wedge Strategy of the antievolution crowd, referred to in Prof. Cassone's post below
Thanks to V. Cassone for posting on his debate experience. It is heartening that he reached students on the fence, and I agree that the ID crowd must be engaged. Based on Dr. Cassone's response to my earlier post, I think we are dealing with a semantic issue regarding IC. That's OK, as academics we should not promote anti-semanticism. I argue that biological systems have IC as defined by Behe, which I take to mean that there is a core of components where removing any of more than one of them causes loss of function. This is not exactly what he has written, but it is based on his reply to the many well-known examples of redundancy...redundancy within systems only pushes the problem back a step to the remaining complexity in cells that have lost the redundant components. If this were untrue, then molecular genetics would not have gotten off the ground at all. Although some components of the replisome are dispensible, there is more than one that was found by screens for ts lethals. Some knockout mutations have phenotypes that are the same as other knockout mutations in the same "system". We base our genetic analysis of pathways on this. Behe's IC as defined is utterly trivial. The problem, of course, is that Behe wants the unwary to take his definition of IC and reinterpret the definition to mean that an IC system is one where coevolution of the parts is impossible. That is a non sequitur, and is one of the many sleazy rhetorical tricks involved in the ID movement. I don't see any compelling reasons to expect to find IC in this stealth sense from the flagella, the clotting cascade, the visual system, or anything else.
On February 15, 2005, I debated Dr. Michael Behe concerning the question whether Intelligent Design is Necessary for Biological Complexity. Frankly, I think I afforded myself well, but I doubt I convinced the hardcore creationists. Most of the reasons for this is that my arguments were primarily biological, and these people clearly do not know any biology. I cannot say if I "beat" Dr. Behe; others will have to determine that. However, I received more than 80 congratulatory e-mails indicating that I had made my case well. I received at least 10 e-mails from students saying that they were uncertain about the issue going in, but that my arguments convinced them that, at the very least, Behe's arguments held no water. Now, I will take issue with Dr. Hu's criticism that there are irreducibly complex systems in biology. There is no evidence for irreducible complexity at the level of genetic sequences and little evidence for irreducible complexity when using Behe's non-biologicalconcepts for "parts". I am surprised that Dr. Hu would think there is irreducible complexity in bacterial systems. I'm not a microbiologist, and I don't play one on television, but if there were irreducible complexity, suppressor screens should not work. They do. Further, manipulation of E. coli genes, Dr. Hu's organism of choice, encoding components of the flagellum consistently result in less than optimal function, but function nonetheless. This in and of itself nullifies Behe's argument that irreducibly complex systems do not work at all (not just work poorly) if a "part" is removed. Remove MotA, and you still have a functional flagellum (References available upon request) The bacterial flagellum is Behe's best example. Even this example has no validity. So, to put it succinctly, Behe's arguments are hogwash. I was just being polite at the debate. Finally, one really needs to address the motives of the ID and IC people. I encourage everyone to read the Wedge Strategy (http://www.antievolution.org/features/wedge.html). When I read this document, my skin begins to crawl, and I am struck by the notion that the Ayatollah Khomeini was really a moderate compared to these people. I am also aware of the fact that my acceptance of debating Dr. Behe plays into the Discovery Institute's hands. They just want a bona fide scientist to be on the same stage as their champion, so that they can say later that scientists take their ridiculous schemes (not theories) seriously. Still, the time has passed that ignoring this threat to scientific research and education is a valid approach. Now, we must all engage them. Keep vigilant. This will get worse before it gets better- Vincent Cassone
I've asked Vinnie Cassone to be a guest blogger so he can tell us what it was like to debate Behe...and so he can respond to my critiques.
I was just talking to one of my colleagues, and while we agreed that it was important for Vinnie to stand up and debate Behe, there were some things we didn't think were effective in his presentation. So...saying up front that he did an important thing last night...what would I have done differently than Vinnie if I had been on the stage instead of him? My take on ID1 is different, and includes a combination of what Pete Dunkelberg has written over at Talkdesign.org; an extended version of the insights of the "skyscraper guy" last night, and some odds and ends. Here's what I would have tried to do:
IC exists in Biology Behe defines IC as: Irreducible complexity is just a fancy phrase I use to mean a single system which is composed of several interacting parts, and where the removal of any one of the parts causes the system to cease functioning.If you choose the definitions of part, system, and function appropriately, almost everything is IC. I can't think of any gene product that doesn't act in at least one multistep pathway or complex. If we knock out any of the 5 genes in the trp operon, E. coli can't make any tryptophan. By Behe's definition the trp biosynthetic pathway is IC. The same argument applies to everything I can think of in biochemistry, and many proteins are needed for more than just making tryptophan. There are many, like the clotting factors in mice, where knocking out a component is lethal. There are lots of lethal loss of function mutations, so it could be argued that every one of these represents a part in an IC system. Behe's choice of complex systems like the flagellum and the clotting cascade are either misguided, or if you give him more credit than I do, insidiously crafted to lure his critics into battle on the wrong ground. ID critics focus on the requirement that breaking any part kill the system, but Behe doesn't really mean this. When pressed he retreats to the idea that there is an IC core that satisfies the requirement for depending on multiple parts. In other words, if the ID critique of DEM has any validity, finding redundancy of the same kind or extra bits doesn't help...the most primitive flagellum that acts as a flagellum is still very complex2. IC can arise through variation and selection So far it's sounding like the above is all in favor of ID: IC is not just in a few systems, it's everywhere, and the ability to take away some parts does not eliminate the complexity problem. Does this mean I think ID is needed3 to explain complexity? Absolutely not. Although there are many, many, cases where knocking out a part kills a function, it is important to remember that breaking parts is not the same as going backward in evolutionary time. This is where the "skyscraper guy" made an important point. Once a species acquires a complex, essential system, it can be elaborated and may be duplicated in its descendants, but it is rare for an essential system to be become nonessential and then to be lost. However, whether or not a system is essential depends on circumstances...complex systems can degenerate (but see this cool post from Carl Zimmer; "degeneration" isn't always the right way to think of loss) and different systems can reevolve to fulfill a lost function as organisms move into different niches - the fins of cetaceans (whales and dolphins) come to mind. In any case, it is not at all surprising that complex systems, once evolved, need most of their parts to work. The question is not whether complexity exists, its whether non-ID mechanisms are adequate to build the systems. The core IC argument requires not only that plausible precursors to any complex system not only fail at their current functions, but also at whatever their former functions were along the way. Nature doesn't care whether evolution is direct or indirect. Selection only operates on the resultant fitness. This has been covered in gory detail for many, many examples by others. Last night Mike Manson gave a good description of how this applies to the bacterial flagellum; parts are related to proteins that do other things. The flagellum itself does not need to rotate to contribute to a role in adhesion and biofilm formation, and there are many non-motor driven projections from cells. At the deepest level, proteins function by folding into 3-D structures with the ability to bind things and change shape. We know that random variation on common structures can provide the ability to bind lots of different ligands because we can select variant peptides that bind to lots of different things. In vitro evolution of RNA molecules, starting from randomized sequences, can yield new binding activities...and intermediates can be identified and characterized. There are technical blocks to recapitulating the variety and efficiency of real biological molecules, but these are not surprising when you consider the almost incomprehensively massive differences in scale and time. For a sense of this, consider the fact that the time it took for the Colorado River to carve out the Grand Canyon is thought to be on the order of <50 M years by noncreationists (not surprisingly, the Institute for Creation Research disagrees). This is on the order of 1-2% of the age of oldest dated cyanobacterial stromolites. Life has had a big head start. What these artificial baby step selection experiments show us only reinforces what Darwin himself spells out in the very first chapter of The Origin of Species The great power of this principle of selection is not hypothetical. It is certain that several of our eminent breeders have, even within a single lifetime, modified to a large extent their breeds of cattle and sheep. In order fully to realise what they have done it is almost necessary to read several of the many treatises devoted to this subject, and to inspect the animals. Breeders habitually speak of an animal's organisation as something plastic, which they can model almost as they please.Note that the breeders of Darwin's time, however intelligent, were not designing breeds. They knew nothing of genes and genetics. They were just biasing the random walk of variation among the progeny of their existing stocks, just as E. coli uses a biased random walk to swim up a chemical gradient without having a way to measure directional differences in solute concentrations. Given billions of years of time and billions of organisms, the variation Nature had to work with would include not just the allelic variation available to Darwin's breeders but also a slow but continuous input of newly changed protein sequences from mutations, mating, horizontal gene transfer, and recombination. What we see in every genome sequence is consistent with this. What kind of evidence do we need? Despite all this, it is a commonplace of creationist and ID critiques of DEM that there is no compelling evidence for evolution by gradual selection on variation. Behe writes: None of the papers [in Journal of Molecular Evolution] discussed detailed models for intermediates [emph. added] in the development of complex biomolecular structures. In the past ten years JME has published over a thousand papers. Of these, about one hundred discussed the chemical synthesis of molecules thought to be necessary for the origin of life, about 50 proposed mathematical models to improve sequence analysis, and about 800 were analyses of sequences. There were ZERO papers discussing detailed models for intermediates in the development of complex biomolecular structures. This is not a peculiarity of JME. No papers are to be found that discuss detailed models for intermediates in the development of complex biomolecular structures in the Proceedings of the National Academy of Science, Nature, Science, the Journal of Molecular Biology or, to my knowledge, any science journal whatsoever.By demanding omniscience and time travel, Behe rationalizes ignoring a fairly vast literature on molecular evolution. Most of those 800 papers on sequence analysis undoubtedly include evolutionary inferences about the changes made between intermediates. Five years before Behe made this claim, Nature published a very cool paper by Steve Benner's lab on resurrecting protein sequences from extinct evolutionary intermediates in the artiodactyls (ancestors of hooved mammals like cows, sheep, and goats)...but this doesn't count for Behe either. Behe and others criticize speculation about evolution of complex structures as "Just-So Stories", and they are correct that any particular proposal for a pathway is highly speculative. But these speculations are thought experiments to examine the question of what is possible, not necessarily what actually happened. They are meant as examples from possible evolutionary history space, which is large. For a pair of proteins that each differ by 50 amino acid substitutions from a common ancestor, there are at least 50! = approx 3 x 1064 substitution pathways for the how they arose. These are not equiprobable, but there is no shortage of plausible mechanisms. Thankfully, no one is writing papers evaluating these pathways one at a time. IDers and other creationists are obsessed with the idea that all intermediates must be identified before there is support for a model. This is especially strange coming from a fellow biochemist like Behe. The detailed structures of the transition states for many enzyme reactions are not fully known, but no one argues that supernatural explanations are needed to explain the reactions (I hope). In fact, it is insane to only believe things that can be specified at this level of detail. No one does asks me if I got to work via teleportation when all they see is me at my desk and my car in the parking lot. Can they completely rule out the possibility that I was teleported to my desk? No...they lack detailed intermediates. Is this a useful way of thinking? As any amateur philosopher knows, no one can disprove ID. Scientists do not reject ID based on being able to disprove it, we reject it based on parsimony. Darwinian mechanisms, genetic drift, and endosymbiosis were all incorporated into mainstream biology because they all affect what we look for in our data, and help us to interpret what we find. We do not find ID to be useful for improving our investigations of the living things. How will ID inform what we look for in biology? What experiments should I do based on the ID worldview? Nine years after Darwin's Black Box, I still don't see where ID science is supposed to be going. The burden of proof should not be on biologists to disprove ID; it should be on ID to show how it is useful. 1Abbreviations used: ID = Intelligent Design; IC = Irreducible Complexity; DEM = Darwinian Evolutionary Mechanisms (variation+selection+time) 2These arguments do address the question of whether ID is needed more recently - i.e. in the past 100 M years or so - well before the appearance of humans. Is there anyone who wants special creation for E. coli and Thermoplasma but not for humans and other primates. 3The issue is not whether or not ID can be disproven. Most theists believe a designer is involved in both the complex and the simple. The question is whether or not adding a designer is necessary to account for what we observe.
The Battalion is the local student newspaper here at TAMU. Here is their coverage of last night's debate. It's fixed now, but earlier there was a misplaced photo/caption that I found amusing: 
The crash shown is actually from the lead story on the front page. --update 3/22/05-- alas, the original screencap has been lost. This photo was under a headline about the debate.
Earlier tonight, the Behe-Cassone ID debate was held. The post below gives a reconstruction of some of what was said. Here's the post-game analysis. As with any post-game analysis, it should be noted that it is a lot easier to kibitz from the sidelines than to perform under pressure during the game. That said, here we go: My take-home messages :
I would have thought that nine years after the publication of Darwin's Black Box, he could spend some time on something other than the bacterial flagellum and the clotting cascade. If I was playing Devil's advocate for ID, I bet could come up with more and better examples. He clearly wants to use the clotting cascade to beat up Russ Doolittle, but his repetition of "Russ Doolittle doesn't know" seemed really lame and became grating by the end of the evening. Of course, it is not at all surprising that he didn't present evidence for design...his argument reduces to: No evidence short of omniscience is good enough for me. One wonders if he would have voted to acquit OJ Simpson, since there is no detailed rigorous record of everything that happened between the time OJ was last seen and when the bodies of Nicole Brown Simpson and Ronald Goldman were found. That said, he did what I expected and pounced on at least two openings given him by Cassone. First, the mousetrap evolution argument. This was a batting practice fastball - Cassone should have known better than to try to sneak this one by Behe. Second, the argument of poor design...his response was not only reasonable, it was well-tuned to the audience; they had just had a discussion of "Job and the Problem of Evil" the day before - so a little blind spot is going to bother them about God's abilities? Cassone Cassone's presentation was based on a talk he gave to the Biology Dept. on ID, and I didn't really like it then for similar reasons. What I might have done differently will be saved for a different post. As mentioned above, the mousetrap evolution part of his talk was a bad idea - not only was it predictable that Behe would have seen it before, but also the nature of the rebuttal was predictable: mousetraps are products of design. Talking about mousetraps, Mt. Rushmore, watches, or cars and trucks is to fight on Behe's home turf. The section on diploids had many of us scratching our heads. The payoff was a letdown, and similarly, the redundancy argument invites the question Behe raised: so where did the first ones come from? The answer isn't in redundancy within visual systems - it's in bacterial rhodopsin and a zillion signal transduction systems that have nothing to do with vision. Cassone was stronger in his rebuttal, where he engaged Behe's specific cases and led him to repeat Russ Doolittle over and over. Cassone was also strong on the compatibility and complementarity of religion and science.
Just got back from the Behe-Cassone debate sponsored by the TAMU Veritas Forum at Rudder Auditorium. This is a reconstruction from my notes. Editorial comments will be inserted but I'll try to mostly recount what happened (very sketchily) and reserve analysis for another post. The debate was moderated by former Dean, successful Chemical Engineer, and investment manager Dr. Ide Trotter. Trotter did a fine job, starting with laying out the ground rules with respect to what was not up for debate, including:
Both speakers used Powerpoint for their ~35 min opening statements. Behe's opening statement: Behe spoke first. His talk closely followed his recent NYT op-ed. He laid out five parts to his talk:
Design can be deduced from physical structures - This was the Mt. Rushmore argument. Biological systems appear to be designed - quotations from various scientists, including ID opponents, using words like design and machine. Cites Crick/Dawkins/Paley/Alberts/Issue of Cell containing lots of titles. States that use of the term machine is meant literally. So far, it's the NYT piece. There are structural obstacles to gradual evolution - Quotes Darwin : If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case.(Origin of Species)Emphasizes "my theory would absolutely break down". Introduces the idea of IC (irreducible complexity) via the famous mousetrap analogy. Uses the flagellum as an example and quotes DeRosier as saying how it looks more like a human design than anything else in biology. Points out not only that it's easy to break and has lots of components, but also that getting all the components together should be hard for DEM. Darwinian explanation rely on "undisciplined imagination"- Then he makes the claim that there are no studies showing a mechanism for evolution by mutation/selection [in detail, rigorous...lots of qualifiers are implicit] Cites F. Harold from The Way of the Cell "We should reject, as a matter of principle, the substitution of intelligent design for the dialogue of chance and necessity; but we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical system, only a variety of wishful speculations."[emph by Behe...this is also quoted here]Behe objects that Franklin does not spell out the principle, and shows a slide with the Ghostbusters logo. The principle is to exclude the supernatural. Brings up the clotting cascade, and points out an error made by Russ Doolittle in a Boston Review article in 1997. Doolittle mischaracterized a 1996 paper on double knockout mice lacking two proteins in the clotting cascade. Behe introduces a theme for the evening: if Russ Doolittle, the world's expert, makes mistakes about the clotting cascade, then there is no evidence that it arose by DEM. There is strong evidence for Design and little for Darwinian evolutionary mechanisms-this is more of a conclusion than an argument. Cassone's opening statement Cassone's title: "Irreducible Complexity?!? My Dear Dr. Behe, Living Organisms Are Redundantly Complex with Interchangeable Molecular Parts, which, if Designed at All, are Designed with a Distinct Lack of Intelligence!! Rather, the more Parsimonious Explanation is that They Have Evolved By a Combination of Mutation, Selection, Genetic Drift and an Immense Expanse of Billions of Years of Good-Old-Fashioned Time"Shorter version: Biological complex systems are multiply redundant and suboptimally designed. Major questions addressed by biology/evolution
Venus flytraps and sundews by analogy to mousetraps. Related, missing parts to change mechanism but keep function. What are parts? Importance of DNA as hereditary material. Brings in Mendel, dominant and recessive traits [where is he going with this?]. Systems in diploid organisms are not IC because there are at least two copies of any autosomal gene. Extended discussion of visual systems [his area of expertise]. Redundancy of components rhodopsins, transducins, channels. Similar proteins in many other light-sensing systems. Design failure - rods and cones placed to require blind spot...design not intelligent. Behe's rebuttal: Problems with Behe's ppt for the rebuttal (he has a sluggish remote - not his computer). The bad design argument is an argument from ignorance. May be reasons; in the case of retina, arrangement improves blood supply. Redundancy of an IC system does not address how the first one got there. Mousetraps vs rat traps with two springs - removing one hampers, but the basic mechanism is IC. "Could not possibly" is too weak a standard. Cottage industry of mousetrap design analysis since his book. Mousetraps may have evolved, but involved ID. Cassone's rebuttal: His slides work. Seems he was saving some stuff knowing he got to go last: Although KO mice might need the whole clotting cascade, other vertebrates don't. Flagellar mutants that still work, so not IC. Archael flagella are simpler. Although ID claims to not be about religion, it's proponents openly use it as a wedge strategy to counter materialism. DEM/materialistic science is not incompatible with the American way. Many conventional biologists (ID skeptics) go to church too. Most religions don't question DEM. highlights from the Q&A: Questions were often long-winded, and I took a short break during the questions. Here are some of the ones I found memorable, if not also interesting...but I didn't take thorough notes here. Borrowed parts - borrowing parts from a friend's truck still involves intelligence and not common descent. Social scientist asks long-winded and stereotypical question about whether or not science is about objective truth. Behe says yes. Further discussion thankfully cut off by Trotter. Are there IC systems in biology that nevertheless evolved from non-IC components. Analogy: concrete w/o steel rebar allows short skyscrapers. Rebar makes them stronger and allows taller skyscrapers. Rebar is now an essential component, but it wasn't before. We refer to the questioner as the "skyscraper guy". Cassone says no. In response to various questions, Behe brings up Doolittle a lot. Cassone points out that Mike Manson is in the audience; Trotter invites Mike to comment on the flagellar motor. Mike gives a very good explanation of how this allegedly IC structure is composed of parts that are related to proteins and domains known to function in other systems and for other functions. Points out adhesion function of flagella even if nonmotile. Mike points out that the skyscraper guy had a good question. Behe responds with Russ Doolittle and how even though clotting factors are related to serine proteases, the proteins still have to work together. Mike says that Russ Doolittle isn't here to defend himself, but he is, so he'd be happy to continue with discussion of the flagella. A biology teacher asks whether in light of the lack of evidence for macroevolution, would proof of ID affect research in biology. Cassone: yes. A young woman asks Cassone if he would prefer to live in a world of ID or a world of DEM. Cassone calls being designed boring and chooses DEM. Jim Erickson asks Behe a version of a point I blogged in December: the IC examples are all ancient systems, and Behe grants that once you have an IC system, it can be elaborated by microevolution, duplication, divergence, selection. So what has design contributed in the last 250 million years? Behe answers that we don't know. There could be IC differences between humans and other primates. An anthropologist asks about whether vestigial organs are designed. Behe says conventional evolution can account for loss of function and degeneration. A strange question arguing that Darwinism damaged the history of Genetics for 50 years, based on the time lag between Mendel and the rediscovery of Mendel. Behe disagrees with the questioner, who exclaims "50 years!!" The experimental verifiability question is raised. Cassone mentions computer evolution studies by Lenski. Behe disses Lenski's E. coli work...pointing out that long lab evolution work is only losing complex systems, not gaining them. Out of time, Trotter thanked the speakers and the audience. I'm sure I missed some things, but I think I got the general content.
In preparation for tomorrow night's Behe-Cassone smackdown, here's a link to a recent opinion piece in the NYT - Behe on the four pillars of ID (link is to reprinting in the Houston Chronicle; the NYT site has it in the paid archives now). PZ Myers at Pharyngula provides a thorough fisking, and also notes that Bruce Alberts objects to the way Behe uses his statements in the piece linked above: That I was unaware of the complexity of living things as a student should not be surprising. In fact, the majestic chemistry of life should be astounding to everyone. But these facts should not be misrepresented as support for the idea that life's molecular complexity is a result of "intelligent design." To the contrary, modern scientific views of the molecular organization of life are entirely consistent with spontaneous variation and natural selection driving a powerful evolutionary process. Behe argues: The first claim is uncontroversial: We can often recognize the effects of design in nature. For example, unintelligent physical forces like plate tectonics and erosion seem quite sufficient to account for the origin of the Rocky Mountains. Yet they are not enough to explain Mount Rushmore.  PZ Myers points out that this is uninformative; here's why. That we can sometimes, or even often recognize design is certainly true (I'm not sure what Behe means by "in Nature"...is Mt. Rushmore in Nature?). However, it does not follow that anything we think is designed was, in fact, designed. Consider the image on the right. It looks like a profile carved into a mountainside, not unlike Mt. Rushmore. However, New Englanders will recognize this as the Old Man in the Mountain, a natural rock formation that used to be in Franconia Notch State Park in New Hampshire. As identifiers of design, we are subject to both false positives and false negatives. False negatives occur whenever an artful garden fools a visitor into believing that it's a natural setting. False positives occur when we attribute intelligent action to things, like the Old Man in the Mountain, that occur through other mechanisms. Most biologists believe the ID crowd is reporting nothing but false positives. They think we're ignoring true positives. This leads us to Behe's second claim: Which leads to the second claim of the intelligent design argument: The physical marks of design are visible in aspects of biology. This is uncontroversial, too.This is an example of petitio principii aka begging the question or circular reasoning. If one accepts that the physical marks of design are present in biology, then it follows that design is present in biology. QED. So to claim that this is uncontroversial is an extremely clumsy sleight of hand. Don't fall for it. These two "uncontroversial" statements set up the rest of Behe's argument. By claiming that the goal of Darwinism and of ID are to explain design, he concludes that there must be... design. In fact, the controversy between ID and evolutionary biology is in explaining the origins of 1) species and 2) complex systems. Behe's claim to fame is based on promoting the idea that some systems are too complex to have arisen from less complex systems. Design is invoked to explain the existence of systems that are improbable on the basis of random events. But this is a false dichotomy. Darwinian models do not claim that complexity arises from a random walk alone. Selection is needed as a driving force. Behe also claims that: there are no research studies indicating that Darwinian processes can make molecular machines of the complexity we find in the cellSlipperiness abounds again. In fact the literature is rife with research indicating that Darwinian processes can and do account for complex systems. There are no research studies that specify how things happened in sufficient gory detail to satisfy Behe and the ID crowd...a level of detail that is far beyond what most professional biologists bother to worry about. Should we be concerned by the gaps in our understanding? Of course. At many levels we are...that's what a lot of research is about. But we're not concerned with our inability to fully account for the complete genome sequence of every intermediate between the period before the formation of eukaryotes and any modern organism, any more than we're worry about gravitation being wrong when there are deviations in the orbits of celestial bodies...those deviations+what we know about gravitation suggest the existence of masses that we have not yet observed, not angels pushing the stars around. Similarly, the modern evolutionary synthesis gives us ideas about how to narrow the gaps in our understanding...genomic DNA sequences are a gold mine of information about evolutionary history, and scientists are testing hypotheses about how complex systems evolved from simpler ones...one of my favorite areas is how we have started to reconstruct possible ancient proteins, in the same way that we can reconstruct ancient human artefacts based on our best guesses of what they were like. I have yet to see how ID inspires any useful research activity.
Tomorrow night, the head of our Biology Dept. will be debating ID proponent Michael Behe. DEBATE: Is Intelligent Design Necessary for a Full Explanation of the Molecular Structure of Life? 7:00 pm, Rudder Auditorium [Debate with Q&A] Dr. Michael Behe & Dr. Vincent Cassone Behe, of course, is known as one of the leading proponents of the idea of irreducible complexity. His research over the years has been largely on structural transitions in DNA. If it's the same MJ Behe (I think it is), he worked on hemoglobin gelation with Walter Englander in the 1970s. He's currently a Prof. of Biochemistry at Lehigh Univ. Cassone is an expert on the circadian clocks. He's Professor and Head of the Biology Department here at Texas A&M. The debate is sponsored by the Veritas Forum, a Christian group on campus. I'll try to blog the debate - I'm not sure if I will be able to live-blog (depends on network connections).
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