Mike Gene
Reged: Feb 24 2000
Posts: 5080
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In his book, Finding Darwin’s God, Miller finds himself “amused” at Behe’s argument regarding the eukaryotic flagellum, adding, “A phone call to any biologist who had ever actually studied cilia and flagella would have told Behe that he’s wrong in his contention that the 9+2 structure is the only way to make a working cilium or flagellum.” (p.141).
But I can’t find where Behe ever raised this contention.
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ID Think
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leonard
Reged: Aug 30 2001
Posts: 11540
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July, August, September...
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Seek, and ye shall find.
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Ilíon
Reged: Feb 23 2003
Posts: 4401
Loc: Ohio, USA
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9 + 2 *does* equal 11
and 11 *does* look like two pieces of straw *and* may be represented by two pieces of straw
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Darwin's idea was clever in his day,when people didn’t know much about how things work-GilD
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PvM
Unregistered
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Sounds so far like a strawman. At most I have found a reference which mentions that Behe does not discuss any other flagellum than the 9+2 but that by itself is no help.
As far as I can tell Mike's description
[QUOTE]
Unfortunately, Behe’s argument never rested on the 9+2 flagellar arrangement. Contrary to Miller’s assertion, not once did Behe contend that the 9+2 structure is the only way to make a functioning flagellum. Behe does include an illustration of the 9+2 arrangement, but this is a standard illustration borrowed from a standard biochemistry textbook. That’s hardly justification for portraying Behe’s argument as being dependent on the 9+2 arrangement as the focus of his discussion of irreducible complexity.
[/QUOTE]is correct
Yersinia also seems to agree with Mike
[QUOTE]
Sure. Ken Miller had a similar situation with blood clotting, foolishly taking Behe's diagram as the IC system, rather than Behe's qualifications in the fine print of the text. Then again, a great deal of the popular appeal of the IC argument (such as it is) stems from those very complex-looking diagrams and the impression that the systems must be just so or they don't work at all.
But the actual biology is often, "well, really, a fair number of parts are dispensable in various organisms, and there are lots of variations." Thus quibbling about definitions becomes crucial. This in itself undermines the IC argument, because it is a small step from not-required-but-useful to so-useful-its-required. The variations away from 9+2 show that there are alot of ways to build a functional cilium. 3+0, etc., remain important to keep in mind, to show just how much flexibility biology allows.
[/QUOTE]Although I do see some continued confusion about the 9+2 on webpages
[QUOTE]
To work properly, or at all, each cilium engine requires many diverse components, such as dynein and nexin rods and cross-bridges arranged in a structured 9+2 pattern, ATP for energy,
[/QUOTE]Source
I will see what the paper has to say.
Time to get Behe's book
[QUOTE]
I tried to scan in an illustration from Miller's book (pg 142, ppbk), but my scanner has succumed to entropy. Basically, Behe's cilia argument is that the eukaryotic cilia, consisting of a pair of microtubules surrounded by 9 doublet microtubules. Behe asserts that this "9+2" is the simplest known configuration. But Miller points out that while 9+2 is very common,
[/QUOTE]Quote
Where are my books....
One moment
Okay here we go
Figure 5.1 on page 142 "Finding Darwin's God"
[QUOTE]Because text books say that the "9+2" structure is found in everything from single celled algae to human sperm, a biochemist might easily have assumed that this particular patterns was the only one that worked, hence the conclusion of irreducible complexity. A phone call to any biologist who actually studied cilia and flatelly would have told Behe that he's wrong in his contention that the 9+2 is the only way to make a working cilium or flagellum.
[/QUOTE]Hmmm, no reference to an actual claim by Behe.
Verdict: As far as I can tell Miller was wrong in his assertion that Behe contended that the 9+2 is the only way to make a working cilium of flagellum.
Okay here is the only reference so far in DBB
p.59
[QUOTE]
When a cilium is sliced corssways and the cut end is examined by electron microscope, you see nine rodlike structures around the periphery. The rods are called microtubules. When high quality photograhps are close inspected each of the nine microtubules is seen to actually consist of two fused rings.
[/QUOTE]So Behe does describe the structure of the cilium here and does not seem to mention other configurations.
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Mike Gene
Reged: Feb 24 2000
Posts: 5080
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Miller’s misrepresentation of Behe’s position has been uncritically embraced by some:
[QUOTE] One of the examples of irreducible complexity Behe uses is the cilium - a structure used most often for movement by small cells. Cilia are composed of long chains of microtubules bundled together to make a whip-like structure. I remember studying the cilium in my biochemistry class in college. It is very complex. But to be honest, I don't remember all the details. So, I'll borrow a lot here from Kenneth Miller who is a cellular biologist.(5) Dr. Miller was actually amused at Behe's suggestion that the complexity of the cilium is irreducible (remember, even if it was irreducible it could have evolved). Since the cilium is a complex structure and the 9+2 microtubule structure is found everywhere in nature from algae to human sperm cells, it may easily be assumed that this is the only pattern that worked - hence irreducible complexity. But an appeal to any biologist with a knowledge of cilia would have informed Behe that such is not the case. Sperm from the caddis fly have a 9+7 microtubule arrangement. Some mosquito species have a 9+9+1 arrangement. Eel sperm have a 9+0 arrangement (lacking a central microtubule chain altogether). Finally, the protozoan Diplauxis hatti has a 3+0 arrangement in which many of the supposedly indispensable parts of the 9+2 structure are missing. Some of these cilia work better than others. All the species make do. But it is obvious the 9+2 arrangement isn't irreducibly complex. And the existence of so many simpler versions of cilia demonstrates that Behe's central thesis - that the cilium couldn't have "functional precursors" - is flat wrong.
http://members.aol.com/darwinpage/jdgreason.htm [/QUOTE]and
[QUOTE] Chapter 5 examines Michael Behe's irreducible complexity (IC). Behe says structures like the eukaryotic cilium could not possibly have evolved, because their radial 9+2 structure is IC, which means that if a single piece is missing, then the system will not work at all. But Behe, a biochemist, must not know too much about cell biology. Culex mosquitoes have a 9+1 structure, which works just fine; Anguilla sperm have 9+0, which works just fine; some protozoa have 6+0; one protozoan has 3+0; and several other organisms have free form structures with no radial arrangement at all! And they all work - just fine!
http://www.amazon.com/exec/obidos/tg/detail/-/0060175931/104-1025363-3062330?v=glance [/QUOTE]
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ID Think
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PvM
Unregistered
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Hi Mike,
You have a point here and I will see if these websites will correct their errors. I only wish that some ID proponents would similarly take their websites to task but I digress.
It is a minor issue whether or not Behe actually believe that the 9+2 was the only one. It may rightfully be infered from his treatment of the cilia but could be phrased better. It's the only one he describes in DBB and in his search for evolutionary patterns he did not raise these obvious candidates for 'intermediates'.
Do we have evidence that Behe was aware of other than 9+2 cilia? I will be doing some research here nevertheless the fact that cilia exist which are different from the one described by Behe and the lack of Behe mentioning them (as far as I can tell from browsing DBB) is relevant as to the ICness of 9+2.
As Yersinia argues "The variations away from 9+2 show that there are alot of ways to build a functional cilium. 3+0, etc., remain important to keep in mind, to show just how much flexibility biology allows."
I will ask Miller how he reached his conclusion and perhaps we can find out what happened.
I am not happy with Miller's description but I see it as a relative minor issue that can be easily corrected.
Certainly the observation that some creationist websites use the 9+2 argument as well is ironic
[QUOTE]
How Do Cilia Move in Concert? 03/12/2001
Cilia, the microscopic hair-like projections on some single-celled organisms such as Paramecium and in the human body such as the lining of the esophagus and digestive tract, have long puzzled biologists with their ability to beat in synchronized wave patterns. In the March 22 issue of the Biological Proceedings of the Royal Society, two Israeli scientists use 3D modelling to simulate how this motion is achieved and find that the viscosity of the surrounding medium influences the motion.
Right now, cilia are moving in picturesque waves along your throat, sweeping your windpipe clean of contaminants as you breathe. Readers of Michael Behe’s Darwin’s Black Box will remember the cilium as one of his examples of irreducible complexity (structures composed of multiple parts that cannot work unless all the parts are present, therefore could not have evolved by a series of mutations acted on by natural selection). Take a look at this paper to gain an appreciation of the magnitude of the problem. After pages of differential equations and diagrams, the scientists call their work a “simplified model” of the “internal engine.” To work properly, or at all, each cilium engine requires many diverse components, such as dynein and nexin rods and cross-bridges arranged in a structured 9+2 pattern, ATP for energy, the proper membrane voltages and calcium levels, the ability to respond to neighboring cells with the proper timing, and other factors not yet understood. Yet we are asked by the scientific establishment to believe that brainless cells figured out these engineering feats without an Engineer.
Update 03/14/2001: Nature has just published a paper on another of Behe’s examples of irreducibly complex systems: the bacterial flagellum. The flagellum is now seen as a reversible helical propeller that allows the bacterium to switch between running and tumbling modes. The complexity just keeps getting more and more mind-boggling.
Next amazing story. • Next headline on: Human Body. • Next headline on: The Cell and Biochemistry.
[/QUOTE]Source
I think I found the paper "A three-dimensional model for ciliary motion based on the internal 9 + 2 structure"
[QUOTE]
Here we present, to our knowledge, the first modelling platform that enables simulations of three-dimensional (3D) motion of multicilia arrays at a detailed level. It consists of three building blocks: (i) geometric equations for tracking the 3D motion of the cilia, (ii) a hydrodynamic description of the ciliary system, and (iii) model equations for the internal bend generating based on the 9 + 2 structure. The model generates seemingly realistic 3D beat patterns and demonstrates metachronal coordination that evolves autonomously as a result of the hydrodynamic coupling between the cilia. We study the effect of the twisting motion within the cilia and propose a conjecture on a possible role of the radial spokes system.
[/QUOTE]Proceedings: Biological Sciences Volume: 268 Number: 1467 Page: 599 -- 607
May be a false alarm after all.
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Mike Gene
Reged: Feb 24 2000
Posts: 5080
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PvM,
I’m not really concerned about getting changes on another website. I was just documenting how this misrepresentation has spread. Yes, it’s a minor point. But what is annoying is that Miller uses this misrepresentation as part of a carefully crafted ad hominem. He begins with “amusement” that leads up to his “A phone call to any biologist” schtick. This subtle ridicule is then picked up and repeated in the two web cites I found (and who knows where else).
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ID Think
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PvM
Unregistered
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Mike: But what is annoying is that Miller uses this misrepresentation as part of a carefully crafted ad hominem. He begins with “amusement” that leads up to his “A phone call to any biologist” schtick. This subtle ridicule is then picked up and repeated in the two web cites I found (and who knows where else).
That annoys me as well. ID arguments back and forth have become way too personal. I am surely not free of blame either.
When I stated " I am not happy with Miller's description " I was refering to his ad hominem introduction to a good argument. Totally uncalled for I agree.
I guess we get to agree occasionally :-)
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Mike Gene
Reged: Feb 24 2000
Posts: 5080
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PvM,
It's nice we can agree on something. I guess that's a good way to terminate this latest round on ARN. See ya next time around.
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ID Think
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