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Author Topic:   Behe's Irreducible Complexity Is Refuted
NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 106 of 223 (91474)
03-09-2004 9:41 PM
Reply to: Message 105 by DNAunion
03-09-2004 7:15 PM


No, I'm not saying that. I am saying that it is IRRELEVANT whether or not loss of function occurs when one of the ossicles is removed because the system is not IC according to Behe's statements.
Is this definition the Hambre gave earliy correct?
quote:
A single system composed of several well-matched, interacting parts that contribute to the basic function of the system, wherein the removal of any one of the parts causes the system to effectively cease functioning. (Darwin's Black Box, 39)
How is the middle ear not IC? What would it have to be like to be IC if you think it is not?

This message is a reply to:
 Message 105 by DNAunion, posted 03-09-2004 7:15 PM DNAunion has replied

Replies to this message:
 Message 107 by DNAunion, posted 03-09-2004 10:48 PM NosyNed has replied
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DNAunion
Inactive Member


Message 107 of 223 (91489)
03-09-2004 10:48 PM
Reply to: Message 106 by NosyNed
03-09-2004 9:41 PM


quote:
No, I'm not saying that. I am saying that it is IRRELEVANT whether or not loss of function occurs when one of the ossicles is removed because the system is not IC according to Behe's statements.
quote:
NosyNed: Is this definition the Hambre gave earliy correct?
----------------------------------------------------------------------
A single system composed of several well-matched, interacting parts that contribute to the basic function of the system, wherein the removal of any one of the parts causes the system to effectively cease functioning. (Darwin's Black Box, 39)
----------------------------------------------------------------------
That definition is correct. But as with many/most concepts, a one-sentence definition doesn't say it all. After all, if that one sentence contained everything Behe wanted to say about IC, he wouldn't have written a book. In his book, Behe goes on to explain things more, such as what he does NOT means by a single system (an integrated system of systems doesn't count) as well as giving a better idea of what he means by parts.
quote:
NosyNed: How is the middle ear not IC?
Okay, looks like you guys are finally settling on the middle ear (and not the whole hearing system) as the system under consideration. Let's stick with that.
In this thread, several functions have been mentioned for the ossicles. But as I pointed out earlier, mere amplification is not what most people have mentioned. So I propose that we all accept transmission of force from the tympanic membrane to the oval window as being the function of the ossicles.
So...
SYSTEM = ossicles
FUNCTION = transmission of force from tympanic membrane to oval window
All agreed?

This message is a reply to:
 Message 106 by NosyNed, posted 03-09-2004 9:41 PM NosyNed has replied

Replies to this message:
 Message 108 by NosyNed, posted 03-10-2004 12:37 AM DNAunion has replied

  
NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 108 of 223 (91498)
03-10-2004 12:37 AM
Reply to: Message 107 by DNAunion
03-09-2004 10:48 PM


No, I don't agree on "the" function. That is being a bit silly. The ossicle perform more than one necessary function. If the hearing would not work without those functions why is one of them 'the' function? Why even worry about it actually?
The ossicles perform amplification, attenuation, transmission and impdedance matching. I suppose if one of them is "the" function it would be transmission. If amplification, attenuation or impdendence matching weren't working some volumes of some frequencies would still be heard. If transmission isn't working there is no hearing (or at least very, very little).
But for now, for the sake of argument, ok, 'the' function is whatever you want it to be.

This message is a reply to:
 Message 107 by DNAunion, posted 03-09-2004 10:48 PM DNAunion has replied

Replies to this message:
 Message 111 by DNAunion, posted 03-10-2004 8:25 AM NosyNed has replied

  
Mammuthus
Member (Idle past 6475 days)
Posts: 3085
From: Munich, Germany
Joined: 08-09-2002


Message 109 of 223 (91510)
03-10-2004 4:09 AM
Reply to: Message 88 by DNAunion
03-09-2004 8:51 AM


Re: ..or maybe actin is there after all....
However, knocking out actin makes for some pretty nasty mutants...also major or minor component is rather arbitrary. If knocking out a gene lowers fitness (even if the organism survives) it is still a major component in its pathway.
Cell Struct Funct. 1998 Oct;23(5):273-81. Related Articles, Links
Recovery of flagellar inner-arm dynein and the fertilization tubule in Chlamydomonas ida5 mutant by transformation with actin genes.
Ohara A, Kato-Minoura T, Kamiya R, Hirono M.
Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan.
The ida5 mutant of Chlamydomonas, first isolated as a mutant lacking a subset of axonemal inner-arm dyneins, has recently been shown to lack conventional actin owing to a serious mutation in its gene. It lacks inner-arm dyneins probably because actin is an essential subunit for their assembly. In addition, male gametes of ida5 are unable to produce the fertilization tubule, a structure that contains a core of actin filament bundles. To establish that those observed deficiencies are solely attributable to the loss of actin, and to provide a basis for future studies on the actin function in this organism, we examined in this study whether transformation of this mutant with cloned actin genes can rescue the mutant phenotypes. Cotransformation of the double mutant ida5arg2 with the wild-type actin gene and arginino-succinate lyase gene that suppresses the arg2 mutation yielded several transformants that displayed increased motility. All of them were found to have acquired the introduced actin gene in the genome and the product actin in the flagella, and regained the missing inner-arm dyneins and wild-type motility. In addition, most transformants also became able to grow the fertilization tubule when mating reaction was induced. In addition to the wild-type actin gene, we also used a chimeric actin gene in which the N-terminal 12 amino-acid sequence of Chlamydomonas actin was replaced by that of the greatly divergent Tetrahymena actin. Transformants with this gene also resulted in recovery of inner-arm dynein and 70-80% of the wild-type level of motility. These results established that the lack of inner-arm dynein and the fertilization tubule in ida5 are consequences of its loss of conventional actin. Furthermore, they demonstrate that Chlamydomonas offers an excellent experimental system with which to study the structure-function relationship of actin by means of mutant analysis.

This message is a reply to:
 Message 88 by DNAunion, posted 03-09-2004 8:51 AM DNAunion has replied

Replies to this message:
 Message 112 by DNAunion, posted 03-10-2004 8:38 AM Mammuthus has replied

  
MrHambre
Member (Idle past 1393 days)
Posts: 1495
From: Framingham, MA, USA
Joined: 06-23-2003


Message 110 of 223 (91516)
03-10-2004 7:20 AM
Reply to: Message 106 by NosyNed
03-09-2004 9:41 PM


When Is a Definition Not a Definition?
NosyNed writes:
quote:
A single system composed of several well-matched, interacting parts that contribute to the basic function of the system, wherein the removal of any one of the parts causes the system to effectively cease functioning. (Darwin's Black Box, 39)
How is the middle ear not IC? What would it have to be like to be IC if you think it is not?
Ned, it may fit the definition of 'irreducibly complex' but it doesn't suit Behe's purposes. That's what the problem is.
What Behe and his acolytes are trying to say is that certain molecular machines are essentially different from others, on no other basis than this arguable (to say the least) notion of 'irreducible complexity.' Therefore the blood clotting cascade, say, is less like the (supposedly non-'IC') hemoglobin molecule and more like a mousetrap or a motorcycle. The bacterial flagellum is less like a type-III secretory system and more like an outboard motor. Darwinism basically denies this sort of nonsense, and declares that molecular machines are just like all biological structures: the product of billions of years of variation and selection.
regards,
Esteban Hambre

This message is a reply to:
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DNAunion
Inactive Member


Message 111 of 223 (91526)
03-10-2004 8:25 AM
Reply to: Message 108 by NosyNed
03-10-2004 12:37 AM


quote:
DNAunion: In this thread, several functions have been mentioned for the ossicles. But as I pointed out earlier, mere amplification is not what most people have mentioned. So I propose that we all accept transmission of force from the tympanic membrane to the oval window as being the function of the ossicles.
So...
FUNCTION = transmission of force from tympanic membrane to oval window
All agreed?
quote:
NosyNed: No, I don't agree on "the" function. That is being a bit silly. The ossicle perform more than one necessary function. If the hearing would not work without those functions why is one of them 'the' function? Why even worry about it actually?
See, this is why people need to read Behe’s BOOK instead of just his DEFINITION!
Behe spends some time discussing MINIMAL FUNCTION. Here, that concept can help us nail down what the function of the system under consideration is. What could be lost and yet have the system still retain minimal function? Remember, Behe’s argument rests on what is REQUIRED, not on everything that is there.
If the ossicles didn’t provide any amplification for the signal, would minimal function be retained? Yes. So amplification is NOT the function of the ossicles (it’s an additional, accessory function that is not required from minimal function).
If the ossicles didn’t transmit force from the tympanic membrane to the oval window, would minimal function be retained? No. So transmission of force from the tympanic membrane to the oval window should be considered the function of the ossicles.
quote:
NoseyNed: The ossicles perform amplification, attenuation, transmission and impdedance matching. I suppose if one of them is "the" function it would be transmission. If amplification, attenuation or impdendence matching weren't working some volumes of some frequencies would still be heard. If transmission isn't working there is no hearing (or at least very, very little).
Sounds pretty good to me. Note that amplification would still exist without any contribution in amplification from the ossicles themselves due to the differences in size and mass of the tympanic membrane and the oval window.
quote:
NosyNed: But for now, for the sake of argument, ok, 'the' function is whatever you want it to be.
Sorry, not good enough. That leaves the possibility of "moving the goal post" later. Either you — plural, mind you - actually accept that the function of the ossicles is transmission of force from the tympanic membrane to the oval window (and the debate progresses) or you don’t (and the debate is at a standstill).
[This message has been edited by DNAunion, 03-10-2004]

This message is a reply to:
 Message 108 by NosyNed, posted 03-10-2004 12:37 AM NosyNed has replied

Replies to this message:
 Message 114 by NosyNed, posted 03-10-2004 10:06 AM DNAunion has not replied

  
DNAunion
Inactive Member


Message 112 of 223 (91528)
03-10-2004 8:38 AM
Reply to: Message 109 by Mammuthus
03-10-2004 4:09 AM


Re: ..or maybe actin is there after all....
quote:
However, knocking out actin makes for some pretty nasty mutants...also major or minor component is rather arbitrary. If knocking out a gene lowers fitness (even if the organism survives) it is still a major component in its pathway.
No, it's not. Lowered fitness indicates a reduction in system function, NOT loss of minimal function. If minimal function is retained, the system is still operational and the "missing part" is not a required part.
quote:
[abstract] The ida5 mutant of Chlamydomonas, first isolated as a mutant lacking a subset of axonemal inner-arm dyneins, has recently been shown to lack conventional actin owing to a serious mutation in its gene. It lacks inner-arm dyneins probably because actin is an essential subunit for their assembly.
The first sentence indicates that ONLY A SUBSET of the axonemal inner-arm dyneins is lacking: NOT ALL OF THEM. Some inner-arm dyneins were present even when actin was not. (The second sentence is less clear).
Furthermore, the following from the abstract indicates that minimal function was retained in the absence of actin since the reintroduction of actin merely increased motility (i.e., they had motility in the absence of actin, but adding actin increased it).
quote:
[abstract] "Cotransformation of the double mutant ida5arg2 with the wild-type actin gene and arginino-succinate lyase gene that suppresses the arg2 mutation yielded several transformants that displayed increased motility."
[This message has been edited by DNAunion, 03-10-2004]

This message is a reply to:
 Message 109 by Mammuthus, posted 03-10-2004 4:09 AM Mammuthus has replied

Replies to this message:
 Message 113 by Mammuthus, posted 03-10-2004 9:04 AM DNAunion has replied

  
Mammuthus
Member (Idle past 6475 days)
Posts: 3085
From: Munich, Germany
Joined: 08-09-2002


Message 113 of 223 (91530)
03-10-2004 9:04 AM
Reply to: Message 112 by DNAunion
03-10-2004 8:38 AM


Re: ..or maybe actin is there after all....
quote:
No, it's not. Lowered fitness indicates a reduction in system function, NOT loss of minimal function. If minimal function is retained, the system is still operational and the "missing part" is not a required part.
Then you clearly must not consider any of the various muscular dystrophies as a result of mutations in various parts of the dystrophin, utrophin etc. complex to be particularly important either though they almost universally severely impair motility of those afflicted and ultimately result in death. In any case, the lowered fitness of the actin mutants would remove those individuals from the population if not sustained by the artificial environment of the lab..thus it is still a critical function. They would not have been observed as mutants were it not for the impaired function. If you chose to view only those mutants that completely ablate a function as critical then this is a fairly esoteric view of mutation.
In any case, your original point was that using textbooks you could not find references of any significant involvement of actin in cilia or flagella and this is clearly wrong.

This message is a reply to:
 Message 112 by DNAunion, posted 03-10-2004 8:38 AM DNAunion has replied

Replies to this message:
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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 114 of 223 (91537)
03-10-2004 10:06 AM
Reply to: Message 111 by DNAunion
03-10-2004 8:25 AM


Ok it is transmission. With an ossicle removed the hearing remaining by bone conduction is so very minimal that the individual is deaf.
added by edit
I don't think there would be any amplification with an ossicle removed. The middle ear is air filled. I'd bet that there would be effectively no vibration transmitted through the air to the fluid of the middle ear.
[This message has been edited by NosyNed, 03-10-2004]

This message is a reply to:
 Message 111 by DNAunion, posted 03-10-2004 8:25 AM DNAunion has not replied

  
Loudmouth
Inactive Member


Message 115 of 223 (91550)
03-10-2004 11:07 AM


DNAUnion,
Since I started the thread, I will take the initiative and lay it out for you.
IC system: Mammalian middle ear ossicles (stapes, malleus, and incus).
Function: Transfer soundwaves from the outer tympanum to the oval window of the inner ear.
Argument for system being IC: Removal of just one unit (ossicle) will abolish the function of the whole system, sound waves will not transfer from the outer tympanum to the oval window of the inner ear.
You claim that Behe excludes macroscopic IC systems. I would like a reference for this. Again, this is Behe's definition of IC from this page:
In 1996, the Free Press published a book by Lehigh University biochemist and intelligent design advocate Michael Behe called Darwin's Black Box: The Biochemical Challenge to Evolution. The book's central thesis is that many biological systems are "irreducibly complex" at the molecular level. Behe gives the following definition of irreducible complexity:
"By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning. An irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional. An irreducibly complex biological system, if there is such a thing, would be a powerful challenge to Darwinian evolution." (p. 39)
I will concede that the intro to the Behe quote does say "at the molecular level". However, the definition itself does not exclude macroscopic IC systems. You do have a point that Behe meant for his definition to apply only to molecular systems. However, the evolutionary pathways that have been hypothesized for creating molecular IC systems are the same ones evidenced in macroscopic IC systems.
For Behe to claim that such indirect pathways are possible but inadequate he must first have 2 things.
1. The complete history of how that molecular IC system came about. Behe must show how each step in the actual development of the current day IC system were such as to exclude evolutionary pathways. For example, he must show the step by step development of the bacterial flagella. The observed complete history, not Behe's just so stories.
2. Behe must show how indirect evolutionary pathways that resulted in macroscopic/skeletal IC systems do not apply to molecular IC systems. He says that co-aptation is not an option for molecular IC systems, but this seems to be an ad hoc hypothesis used to exclude counter-evidence. His logic for excluding indirect evolutionary pathways must be based on evidence, not his own incredulity.
Really, there is nothing to refute except Behe's own incredulity of possible indirect evolutionary pathways. I guess the only way to refute Behe's IC via ID hypothesis is to show that Behe does believe that indirect pathways can develop molecular IC systems. I refuted the notion that indirect evolutionary pathways can develop IC systems in the absence of Behe's incredulity.
And one more question for DNAUnion, and I would really like an answer in order to make this debate move along. Why does Behe exclude macroscopic/skeletal IC systems? It would seem that if such systems came about in the fossil record in "one fell swoop", his theory would only be strengthened. It would be like evolutionists discounting genetic data that shows no common ancestor but relying on morphology alone to show common ancestry. You can't pick and choose once you make predictions.

Replies to this message:
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Peter
Member (Idle past 1479 days)
Posts: 2161
From: Cambridgeshire, UK.
Joined: 02-05-2002


Message 116 of 223 (91570)
03-10-2004 12:07 PM
Reply to: Message 74 by DNAunion
03-08-2004 1:42 PM


As I said, which one of the ossicles can you remove
without 'breaking' the vibration transmission system?

This message is a reply to:
 Message 74 by DNAunion, posted 03-08-2004 1:42 PM DNAunion has not replied

  
MrHambre
Member (Idle past 1393 days)
Posts: 1495
From: Framingham, MA, USA
Joined: 06-23-2003


Message 117 of 223 (91582)
03-10-2004 1:11 PM
Reply to: Message 115 by Loudmouth
03-10-2004 11:07 AM


quote:
Loudmouth states: Behe's definition of IC does not exclude macroscopic IC systems.
DNAunion responds: Behe does exclude macroscopic biological systems — such as organs and organ systems - from being IC.
Loudmouth asks: Why does Behe exclude macroscopic/skeletal IC systems?
Good question. After hitching the intelligent-design-creationism wagon to 'irreducible complexity' and defining it for all to see, he then denies that it applies to organs. I've already stated that the human heart sure seems 'IC': if you take away the pump or valves, you don't, well, catch mice, in Behe's words. However, there seem to be problems defining anything as 'IC,' even Behe's pet subject the BacFlag. Ian Musgrave, of the University of Adelaide, argues in his hypothetical scenario for the evolution of the bacterial flagellum that certain parts of the BacFlag can be removed and the system still seems to function.
So the concept of 'IC', then, isn't the crux of the debate. The biological structures themselves may or may not be 'IC' depending on how we define them (don't get me started on Dembski's notion of the BacFlag as a discrete combinatorial artifact) or their function. The argument itself concerns developmental pathways, and Behe realizes that it's much easier to make a convincing case for the evolution of the complex human heart than for the BacFlag.
Behe, obviously, is not the first one to assert that property A is proof of design. It doesn't matter what the proposed litmus test is, what matters is that we're never told why property A is proof that natural law is not inviolable and that divine intervention has taken place in Nature. I don't consider 'irreducible complexity' any better than any other candidate for property A. We have no clear understanding of why natural processes could not conceivably account for an 'IC' system in biology, and certainly no evidence that intelligent agency accounts for the origin of any biological structure.
regards,
Esteban "Cilia Thing" Hambre

This message is a reply to:
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DNAunion
Inactive Member


Message 118 of 223 (91585)
03-10-2004 1:16 PM
Reply to: Message 113 by Mammuthus
03-10-2004 9:04 AM


Re: ..or maybe actin is there after all....
quote:
If you chose to view only those mutants that completely ablate a function as critical then this is a fairly esoteric view of mutation.
You're mixing apples and oranges. When specifically discussing Behe's statements on IC then if a "part" is deleted and the result is just reduction in fitness, not loss of minimal function, then the "part" is not considered to be one of the required parts of the IC system itself.
quote:
In any case, your original point was that using textbooks you could not find references of any significant involvement of actin in cilia or flagella and this is clearly wrong.
Agreed (more or less...your statement makes it sound like it is clearly wrong that I couldn't find any references in my textbooks, which is not the case). I learned something, and already thanked you.
[This message has been edited by DNAunion, 03-10-2004]

This message is a reply to:
 Message 113 by Mammuthus, posted 03-10-2004 9:04 AM Mammuthus has not replied

  
DNAunion
Inactive Member


Message 119 of 223 (91587)
03-10-2004 1:30 PM
Reply to: Message 115 by Loudmouth
03-10-2004 11:07 AM


quote:
loudmouth: You claim that Behe excludes macroscopic IC systems. I would like a reference for this.
Sure...from my personal notes (people can skip the introduction and head straight for the quotes, if they want, without losing anything).
*****************
How many people here truly understand how a computer operates? Probably not many. I would imagine that most users know little more than what button to push to turn the computer on and what a monitor, keyboard, and mouse are (for example, many people point to the system case sitting on their desk or floor and call it a CPU!). Ask them how a CPU fetches instructions and a convincing answer will not be forthcoming. Others know computers in a bit more depth. They know that there is a thing called a hard drive that somehow holds all of their information, and that some kind of a green circuit board inside the system case houses something called the CPU (which they have no idea what it looks like) that does the thinking, etc. Understanding computers a bit better than the first group, those belonging to the second group could give a better explanation of how a computer operates. A few others know a great deal about computers. They know of the binary language and its physical representation as the presence or absence of electric charge; that a hard drive contains multiple rigid platters that spin at high rates and have read-write heads (or separate read heads and write heads) that float on a thin cushion of air just above the platters’ surfaces; and that the BIOS serves as an abstraction layer between the given hardware configuration and the operating system; etc. These people could give a very detailed and convincing explanation of how a computer operates. What we see here is that - as with most everything that science studies - the whole is understood better by learning how its parts operate. And if the parts are themselves composed of smaller parts, an even greater depth of understanding of the whole can be reached by determining how they function too. This process of drilling down to deeper and deeper levels produces a fuller, more-thorough picture of the whole. This is reductionism.
Life. That is what we are interested in. There are different organizational levels of life. Obviously, there is the level of the organism. For centuries, the only organisms known were plants and animals, and the organismal level was as far as biology had delved. Let’s stick with animals, since much of our knowledge of life was originally derived from them. How does an animal work? No one knew for sure. Animals jumped, ate, mated, slept, and died but detailed explanations of how these actions occurred were not known. As time went by, biology dug deeper and found that animals are composed of organ systems, which are themselves composed of organs. Then more detailed explanations could be provided (for example, the path that food took through the body and the fact that blood circulated instead of irrigating the body and then new blood being produced to replace that which was pumped out of the heart). But even this level did not suffice. Further research dug deeper into the tissue and cellular levels of organization. More detailed explanations were available. Indeed, each deeper level that was examined led to a greater understanding of how life operates. And within the last 100 or so years, the innards of the cell have been being investigated, leading to an even more complete understanding of life.
So to understand most fully how life works, and in order to provide the most detailed and convincing explanations for life-related phenomena, we have to dig down to the deepest levels of biological systems: biochemistry (gross anatomy is at far too high of a level).
quote:
With the advent of modern biochemistry we are now able to look at the rock-bottom level of life. (Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p15)
quote:
When Leeuwenhoek used a microscope to see a tinier mite on a tiny flea, it inspired Jonathan Swift to write a ditty anticipating an endless procession of smaller and smaller bugs:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
So naturalists observe, a flea
Has smaller fleas that on him prey;
And these have smaller still to bite ‘em;
And so proceed ad infinitum.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Swift was wrong; the procession does not go on forever. In the late twentieth century we are in the flood tide of research on life, and the end is in sight. The last remaining black box was the cell, which was opened to reveal molecules — the bedrock of nature. Lower we cannot go. Moreover, the work that has already been done on enzymes, other proteins, and nucleic acids has illuminated the principles at work at the ground level of life. Many details remain to be filled in, and some surprises undoubtedly remain. But unlike earlier scientists, who looked at a fish or a heart or a cell and wondered what it was and what made it work, modern scientists are satisfied that the actions of proteins and other molecules are sufficient explanations for the basis of life. From Aristotle to modern biochemistry, one layer after another has been peeled away until the cell — Darwin’s black box — stands open. (Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p13)
quote:
In short, Dawkins’s explanation is only addressed to the level of what is called gross anatomy.
Both Hitching and Dawkins have misdirected their focus. The eye, or indeed almost any large biological structure, consists of a number of discrete systems. The function of the retina alone is the perception of light. The function of the lens is to gather light and focus it. If a lens is used with a retina, the working of the retina is improved, but both retina and lens can work by themselves. Similarly, the muscles that focus the lens or turn the eye function as a contraction apparatus, which can be applied to many different systems. The perception of light by the retina is not dependent upon them. Tear ducts and eyelids are also complex systems, but separable from the function of the retina.
Hitching’s argument is vulnerable because he mistakes an integrated system of systems for a single system, and Dawkins rightly points out the separability of the components. Dawkins, however, merely adds complex systems to complex systems and calls that an explanation. This can be compared to answering the question How is a stereo system made? with the words By plugging a set of speakers into an amplifier, and adding a CD player, radio receiver, and tape deck. (Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p38-39)
quote:
Biochemistry has demonstrated that any biological apparatus involving more than one cell (such as an organ or a tissue) is necessarily an intricate web of many different, identifiable systems of horrendous complexity. The simplest self-sufficient, replicating cell has the capacity to produce thousands of different proteins and other molecules, at different times and under variable conditions. Synthesis, degradation, energy generation, replication, maintenance of cell architecture, mobility, regulation, repair, communication — all of these functions take place is virtually every cell, and each function itself requires the interaction of numerous parts. Because each cell is such an interwoven meshwork of systems, we would be repeating the mistake of Francis Hitching by asking if multicellular structures could have evolved in step-by-step Darwinian fashion. (Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p46)
quote:
The relevant steps in biological processes occur ultimately at the molecular level, so a satisfactory explanation of a biological phenomenon — such as sight, digestion, or immunity — must include its molecular explanation.
Now that the black box of vision has been opened, it is no longer enough for an evolutionary explanation of that power to consider only the anatomical structures of whole eyes, as Darwin did in the nineteenth century (and as popularizers of evolution continue to do today). Each of the anatomical steps and structures that Darwin thought were so simple actually involves staggeringly complicated biochemical processes that cannot be papered over with rhetoric. ...
Thus biochemistry offers a Lilliputian challenge to Darwin. Anatomy is, quite simply, irrelevant to the question of whether evolution could take place on the molecular level. So is the fossil record. It no longer matters whether there are huge gaps in the fossil record or whether the record is as continuous as that of U.S. presidents. And if there are gaps, it does not matter whether they can be explained plausibly. The fossil record has nothing to tell us about whether the interactions of 11-cis-retinal with rhodopsin, transducin, and phosphodiesterase could have developed step-by-step. ... Until recently ... evolutionary biologists could be unconcerned with the molecular details of life because so little was known about them. Now the black box of the cell has been opened, and the infinitesimal world that stands revealed must be explained. (Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p22)

This message is a reply to:
 Message 115 by Loudmouth, posted 03-10-2004 11:07 AM Loudmouth has replied

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 Message 121 by Loudmouth, posted 03-10-2004 3:17 PM DNAunion has replied

  
DNAunion
Inactive Member


Message 120 of 223 (91589)
03-10-2004 1:45 PM
Reply to: Message 115 by Loudmouth
03-10-2004 11:07 AM


quote:
loudmouth: And one more question for DNAUnion, and I would really like an answer in order to make this debate move along. Why does Behe exclude macroscopic/skeletal IC systems?
Besides the quotes I gave above, Behe also says this about the panda’s thumb:
quote:
Even then, why is Gould’s panda scenario incompatible with intelligent-design theory? The panda’s thumb is a black box. It is entirely possible that in the production of the Panda’s thumb, no new irreducibly complex systems were required in the cell. It is possible that the systems that were already present — the systems that make muscle proteins and nerve fibers, that lay down bone and matrix protein, that cause cells to divide for a while and then cease division — were enough. It is possible that these systems were quite sufficient to cause a bone protuberance when some chance event perturbed their normal pattern of operation, and it is possible that natural selection then favored this change. Design theory has nothing to say about a biochemical or biological system unless all of the components of the system are known and it is determined that the system is composed of several interacting parts. Intelligent-design theory can coexist quite peacefully with the panda’s thumb. (Michael Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p229)

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 Message 115 by Loudmouth, posted 03-10-2004 11:07 AM Loudmouth has not replied

  
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