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Amazing how natural selection mastered the physics of the flagellum


Propulsion with a Rotating Elastic Nanorod

Manoel Manghi,1 Xaver Schlagberger,2 and Roland R. Netz2
1Laboratoire de Physique Th´eorique, IRSAMC, Universit´e Paul Sabatier, 31062 Toulouse, France
2Physik Department, Technical University Munich, 85748 Garching, Germany

(Dated: February 9, 2006)

ABSTRACT: The dynamics of a rotating elastic filament is investigated using Stokesian simulations. The filament, straight and tilted with respect to its rotation axis for small driving torques, undergoes at a critical torque a strongly discontinuous shape bifurcation to a helical state. It induces a substantial forward propulsion whatever the sense of rotation: a nanomechanical force-rectification device is established.

Hi Dr. Dembski, Thanks for the link. I will give it some thought. anteater
There is probably not a single contemporary shark species that existed 400 hundred million years ago. Shark ancestors yes, but the same species no. The same can be said for hundreds of other species as well, includlng ourselves. I still maintain that we are the youngest mammal on this planet and in my opinion the last one to ever appear. The presence of Homo sapiens has yet to be documented as having existed before 100,000 years ago. Furthermore, at his first appearance he is indistinguishable from his present morphology. How do all you Darwimpian, chance happy mystics like them indisputable heresies? I hope they give you simultanoeus cramps and constipation. Get out the Exlax and purge yourselves. What a bunch of losers. I love it so! John Davison
What about sharks? They are supposed to be ancient. avocationist
The only thing that natural selection ever did or still does today is to doggedly maintain the status quo. Even at that it typically eventually fails which is why 99.999% of all creatures that ever lived became extinct. The so called living fossils are extremely few and are invariably small creatures with an enormous reproductive potential which allows at least some of their reproductive products to escape the accumulation of lethal genes. The best example is Ostrea virginica, the edible oyster which has remained extant for hundreds of millions of years. To be big is evolutionary bad news and Homo sapiens is definitely on the big size. John Davison
anteater asked: "Sorry to play devil’s advocate, but can’t a GA be thought of as “simulation” of how a landscape can be traversed?" But if the landscape is flat (as in the case of certain IC systems), the GA will only simulate a random walk at best. It's not just a blind watchmaker, but a blind driver driving a flat landscape.... The tautology offered as "proof" by Darwinists is that the landscape is not flat for high complexity IC systems (such a lock-and-key systems). The offer there assertions as "proof", but they are only assertions, not soundly reasoned deductions nor empirical demonstrations. For example, take a self-replicating autocatalytic process such as the Ghadiri peptide and find Darwinian mechanisms which will form it into a biological Turing machine. Talk Origins practically suggests just that in one of their articles on abiogenesis. Anyone familiar with the real details knows this is nonsense. For a landscape to exist the replicator must be amenable to selection, and then a selective pressure must actually exist. In regards to high complexity IC systems, Darwinist merely assert such requirements are satisfied, they never actually demonstrate that they are! A more appropriate model would be a flat landscape with a random walk which never happens upon IC systems. scordova
Miller is not nearly as stubborn as I am and what he thinks means absolutely nothing anyway. He is a Darwimp. John Davison
Donald, Miller is still pushing the notion that homology of components and co-option solve the puzzle of Irreducible Complexity. He's stubborn that way. Scott
The notion that any basic cell structure evolved incrementally is absurd. As a matter of fact the idea that any biological structure evolved incrementally is equally absurd. Please provide a single example. The feathers of Archaeopteryx are indistinguishable from those of a modern pigeon and always were. Incremental evolution is just one more unfounded feature of the Darwinian fairy tale. All evolution was saltational and without intermediate graduated stages. How much longer must this madness persist? John Davison
Sal writes:
Yes indeed it’s amazing what natural selection can do, how it somehow calculated fluid flow mechanics, solved problems in material science, created software to govern the assembly, etc. Truly amazing what Natural Selection can do, and Ken Miller owns some ocean front property in Arizona.
I seem to recall a quote from Miller a few years back, the gist of which was that before we (IDPs) eliminate evolution as an explanation for the flagellum, at least give Miller et.al. a chance to figure out how it works. Miller apparently thought that once science figured out how it worked, figuring out how it evolved would easily follow. Wrong! It turns out that the more we discover about how these nano-biological machines work, the LESS we see how evolution could have produced the system. More knowledge of the operation of these systems has revealed even more layers of complexity that in turn create even more barriers to an evolutionary explanation. Does anyone recall the actual Miller quote on this? DonaldM
Anteater: look here -- http://www.4truth.net/site/apps/nl/content3.asp?c=hiKXLbPNLrF&b=784461&ct=1742245. --WmAD William Dembski
scordova, Sorry to play devil's advocate, but can't a GA be thought of as "simulation" of how a landscape can be traversed? Thus, it doesn't matter if the GA itself was designed, because it simulates how NS/RM may occur (although I think that the analogy is not very strong). Where I see the input of intelligence is the constraining of these GAs. anteater
Yes indeed it's amazing what natural selection can do, how it somehow calculated fluid flow mechanics, solved problems in material science, created software to govern the assembly, etc. Truly amazing what Natural Selection can do, and Ken Miller owns some ocean front property in Arizona. :-) Engineering at the nano-scale is a colossal task. Just ask the chip makers like Intel or semi-conductor capital equipment makers like Applied Materials. It's understandable why a world class nano scientist like Cees Decker is sympathetic to ID. If Unintelligent Natural Selection is the engineer of these nano wonders, why is it that it's practically useless in the engineering of nano-scale systems. Salvador Cordova PS Just to tie up a loose end, occasionally Genetic Algorithms (GAs) are used to help engineer nano systems, but well, those GA's have to be programmed by an intelligent beings, otherwise the evolutionary algorithm is absolutely useless. GA's are sometimes used to explore optimal engineering solutions when there are a large set of possibilities, but it requires an intelligent programmer to have the foresight to design the algorithm. In otherwords, the selection is anything but natural. Furthemore, GAs are incapable of solving a large space of problems in nano-engineering which only an intelligence can solve. Thus even if Natural Selection played a role in the engineering of a flagellum, it could only be a minor role at best. Intelligence is the more important ingredient, and there are some parts of the flagellum that would not be solvable by genetic algorithms. For example, a GA can't solve what your computer passwords are (thankfully!). Things that are not solvable by GA would include lock-and-key or login/password type IC systems. We should then expect when such lock-and-key or login/password type systems are found in biology, Darwinian pathways will not be able to solve them. Such a line of reasoning is not an argument from ignorance, it is a proof by contradiction. Darwinian mechanisms can not have been the cause of large scale biological innovation. scordova

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