Skip to comments.The challenge to Darwin’s theory of evolution – Part 5
Posted on 10/20/2006 9:49:15 AM PDT by DaveLoneRanger
TOKYO -- Unlike his collegue Dr. Scott Minnch, Dr. Michael Behe, professor of biochemistry, did not develop doubts about Darwinism during his years in research. This is because Darwinism was described as a proven fact in many college textbooks and taught accordingly.
What triggered his doubts about Darwinism was a book entitled Evolution: A Theory in Crisis, written by Australian molecular geneticist Michael Denton. He read the book in the latter half of 1980s during spare time while doing research.
Denton presented his critique of neo-Darwinism based on the latest biochemistry achievements of the time. One of the focal points of his presentation was a comparison of the amino-acid sequence of cytochrome-c, a small heme protein loosely associated with the inner membrane of the mitochondrion commonly found in all aerobic organisms. It is an important protein involved in taking in oxygen and generating energy, and is composed of a little more than 100 amino acids. The three-dimensional structure of all types of cytochrome-c is similar and therefore common. But its amino-acid sequence differs according to organisms.
The book points out the remarkable fact that the cytochrome-c amino-acid sequences of bacteria, horses, pigeons, tuna, silkworm moths, wheat and natural yeast are 64 to 69 percent identical.
Neo-Darwinism claims that organisms evolved from bacteria to intermediate types, and then to sophisticated species. However, based on evidence in the book, cytochrome-c of natural yeast is not considered to be an intermediate type between bacteria cytochrome-c and eukaryotic cytochrome-c. The book states: Whatever eukaryotic cytochrome it may be, it is not considered to be an intermediate type between bacteria cytochromes and other eukaryotic cytochromes. This was clearly contrary to neo-Darwinism.
Professor Behe grew indignant over the fact that he could only teach neo-Darwinism in colleges and graduate schools. After this, he started to reflect on his chosen field seriously. He arrived at the term and concept of Irreducible Complexity.
Behe received his Ph.D. in biochemistry at the University of Pennsylvania in 1978. After engaging in the research at the National Institutes of Heath, he became associate professor in 1985 and professor in 1997 at Lehigh University in Bethlehem, Pennsylvania.
Moravian Christian immigrants from Czechoslovakia founded Bethlehem in the 18th century. Professor Behes laboratory is in the Iacocca Hall at Lehigh Universitys Mountaintop campus.
Professor Behe took time to welcome Sekai Nippo reporters to his lab despite his busy schedule. In addition to his teaching and research, he was writing a book. Prominently displayed was a family photo with his wife and all nine of his children.
Asked about his feelings when he coined the term Irreducible Complexity, he said, I think it was in1990. I didn't jump in excitement, but I wrote it down.
It did not take much time to come up with the phrase, he said, "but I was certainly very excited when I did.
"This is because with this phrase I could encapsulate the problems [of Darwinism].
"Usually, if a phrase does not adequately express the issue, people have difficulty understanding it. I found that most people will intuitively understand the issue when they hear the phrase Irreducible Complexity.
Simply speaking, Irreducible Complexity means complexity that cannot be reduced to anything simpler.
The views expressed by this author do not necessarily represent the views of DaveLoneRanger or the creation ping list.
Do not bother attacking the source, for I will not bother to respond to those. I am aware of the affiliations of this paper. Concentrate your disagreements on the substance of the article.
It might be noted that proven scientific theories are said to be facts, whereas they are not facts at all. They are called scientific facts to distinguish them from facts. Evolution is not a theory but a principle. By analogy, if it were mathematical it might be taken as an axiom. Axioms are not susceptible of proof.
That's the definition of irreducible simplicity. No wonder creationists are confused.
If something is irreducibly simple, it doesn't imply a more complex organization couldn't also preform the same function -- complexity you might expect from two or more other functions merging to create a new function. The "simplicity" then coming as the extra unneeded complexity eroded away.
You obviously don't understand the concept of irreducible complexity.
A misnomer. It's irreducible simplicity.
Funny, all of the scientists working on this call it irreducible complexity. Who, besides yourself, uses your phrase?
It's debatable whether they're scientists. But none the less, it is perfectly obvious it is irreducible simplicity -- i.e. it can't get any simpler without failing to function. Of course in most cases even that is likely wrong, as for many functions, just because we can't imagine a simpler arrangement doesn't mean one couldn't exist.
But the main point about irreducible simplicity is that it leads to the notion that two or more functions could merge to create a third function with unneeded or redundant complexity.
Even in "intelligent design" by humans, functions are often overly complex when first proposed, and by trial and error a more simple function is found.
The notion of "irreducibly complex" seems to lead to people believing that something had to self-assemble spontaneously out of random molecules. Such as an amoeba suddenly sprouting an eyeball. It puts creationists in a confused state of mind.
If you go trying to figure the probabilities of an amoeba suddenly developing an eyeball you will get a huge number. But of course you are chasing the wrong mechanism.
Rather, the path to the eyeball was through incremental change on seperate subsystems that then merged with excess complexity of the task, and then eventually lost the unneeded stuff.
Which is very much like human invention -- which also depends heavily on trial and error.
Once again, you display your lack of understanding of "complexity" and, at the same time, reveal your natualistic presuppositions. Also you failed to articulate the creationist position, choosing instead to create a straw man...one that no creationist adheres to.
One definition: "A system performing a given basic function is irreducibly complex if it includes a set of well-matched, mutually interacting, nonarbitrarily individuated parts such that each part in the set is indispensable to maintaining the system's basic, and therefore original, function. The set of these indispensable parts is known as the irreducible core of the system."
Second Definition: "A single system which is composed of several interacting parts that contribute to the basic function, and where the removal of any one of the parts causes the system to effectively cease functioning".
The point isn't to convince you against your religious dogma. A futile task.
The point being made is that all this "certainty of improbability" is based on something that isn't certain at all, and therefore the mathematical calculations of improbability are built on a foundation of straw.
The process by which something becomes "irreducibly simple" offers a REASONABLE alternative to the quantum leaps suggested by proponents of "irreducible complexity."
I presume "irreducible complexity" theory is offered as a scientific arguement, and not a religious one, to convince scientists of the errors of evolutionary theory.
Therefore to be meaningful to scientists it must pass the tests of logic -- such as whether it is imperative. Since there are obvious alternate explanations that are both reasonable and more likely, you really aren't going to find "irreducible complexity" theory making much headway with real scientists.
It's just FYI. If you are happy to preach to the choir, well then it doesn't matter. But if you really want to affect science, you should be aware of the error of your arguments.
Let's see you try to justify the phrase I've highlighted in bold. It'll be pretty amusing watching you make this attempt, because it's twaddle.
For extra amusement, explain how you'd go about determining the "basic" function of a given biological structure. We'll wait.
Then define "system". How do you plan to go about marking where one "system" ends and another "system" begins in a biological organism? Ditto for "parts".
Next, give us a metric for "well-matched". What's the cutoff figure for "well-matched" versus "sorta so-so-matched"?
Next, give a stab at defining "nonarbitrarily individuated". That should be fun.
Creationists are fond of engaging in a lot of fuzzy buzzword blathering when they attempt to do science, but upon examination they're just mouthing stuff that sounds good but can't be pinned down in any way that can be actually tested, validated, falsified, or used to make predictions.
Yeah, that's Behe's definition -- it has the same fuzziness problems as Dembski's. "System"? "Parts"? "Basic"? "Effectively cease"?
But ambiguous language aside, so what? If Behe wants to slap a label on something, that doesn't advance understanding any.
Oh, right, you and Behe and the Jesus-denying Moonie cult that DaveLoneRanger has been quoting from for days now want to claim that a "system" (*cough*) that matches this description must be "unevolvable", right?
Behe's line of "reasoning" for arriving at that conclusion is fatally and unfixably flawed.
Here's some of my own analysis of Behe's central thesis (some from older posts of mine) -- let me know if you find any oversights in it...
The next idea you probably will not like, and that is irreducible complexity.
As an "idea" I like it just fine, and so do evolutionary scientists. The problem is that Behe (and the creationists who follow him) have created a "straw man" version of "IC" which is quite simply incorrect -- but appears to give the conclusion they want.
The original notion of "IC" goes back to Darwin himself. He wrote:"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."That's "Irreducible Complexity" in a nutshell. It's not as if Behe has pointed out anything that biologists (or Darwin) didn't already realize.
-- Charles Darwin, "On the Origin of Species", 1859
But let's examine Darwin's description of "IC" in a bit more detail (emphasis mine):No doubt many organs exist of which we do not know the transitional grades, more especially if we look to much-isolated species, round which, according to my theory, there has been much extinction. Or again, if we look to an organ common to all the members of a large class, for in this latter case the organ must have been first formed at an extremely remote period, since which all the many members of the class have been developed; and in order to discover the early transitional grades through which the organ has passed, we should have to look to very ancient ancestral forms, long since become extinct.Darwin makes two critical points here:
We should be extremely cautious in concluding that an organ could not have been formed by transitional gradations of some kind. Numerous cases could be given amongst the lower animals of the same organ performing at the same time wholly distinct functions; thus the alimentary canal respires, digests, and excretes in the larva of the dragon-fly and in the fish Cobites. In the Hydra, the animal may be turned inside out, and the exterior surface will then digest and the stomach respire. In such cases natural selection might easily specialise, if any advantage were thus gained, a part or organ, which had performed two functions, for one function alone, and thus wholly change its nature by insensible steps. Two distinct organs sometimes perform simultaneously the same function in the same individual; to give one instance, there are fish with gills or branchiae that breathe the air dissolved in the water, at the same time that they breathe free air in their swimbladders, this latter organ having a ductus pneumaticus for its supply, and being divided by highly vascular partitions. In these cases, one of the two organs might with ease be modified and perfected so as to perform all the work by itself, being aided during the process of modification by the other organ; and then this other organ might be modified for some other and quite distinct purpose, or be quite obliterated.
The illustration of the swimbladder in fishes is a good one, because it shows us clearly the highly important fact that an organ originally constructed for one purpose, namely flotation, may be converted into one for a wholly different purpose, namely respiration. The swimbladder has, also, been worked in as an accessory to the auditory organs of certain fish, or, for I do not know which view is now generally held, a part of the auditory apparatus has been worked in as a complement to the swimbladder. All physiologists admit that the swimbladder is homologous, or 'ideally similar,' in position and structure with the lungs of the higher vertebrate animals: hence there seems to me to be no great difficulty in believing that natural selection has actually converted a swimbladder into a lung, or organ used exclusively for respiration.
In considering transitions of organs, it is so important to bear in mind the probability of conversion from one function to another, that I will give one more instance. [Long detail of example snipped] If all pedunculated cirripedes had become extinct, and they have already suffered far more extinction than have sessile cirripedes, who would ever have imagined that the branchiae in this latter family had originally existed as organs for preventing the ova from being washed out of the sack?
-- Charles Darwin, "On the Origin of Species", 1859
1. A modern organ need not have evolved into its present form and function from a precursor which had always performed the same function. Evolution is quite capable of evolving a structure to perform one function, and then turning it to some other "purpose".
2. Organs/structures can reach their present form through a *loss* of function or parts, not just through *addition* of function or parts.
Despite the fact that these observations were laid out in 1859, Behe's version of "Irreducible Complexity" pretends they are not factors, and defines "IC" as something which could not have arisen through stepwise *ADDITIONS* (only) while performing the same function *THROUGHOUT ITS EXISTENCE*.
It's hard to tell whether Behe does this through ignorance or willful dishonesty, but the fact remains that *his* definition and analysis of "IC" is too restrictive. He places too many "rules" on how he will "allow" evolution to reach his examples of "Behe-style IC" structures, while evolution itself *IS NOT RESTRICTED TO THOSE RULES* when it operates. Thus Behe's conclusion that "Behe-style evolution" can not reach "Behe-style IC" hardly tells us anything about whether *real-world* evolution could or could not have produced them.
For specific examples, Behe's example of the "Behe-style IC" flagellum is flawed because flagella are composed of components that bacteria use FOR OTHER PURPOSES and were evolved for those purposes then co-opted (1, 2), and Behe's example of the "Behe-style IC" blood-clotting process is flawed because the biochemistry of blood-clotting is easily reached by adding several steps on top of a more primitive biochemical sequence, *and then REMOVING earlier portions which had become redundant* (1, 2).
Even Behe's trivial mousetrap example turns out to not actually be "IC".
The usual qualitative formulation is: "An irreducibly complex system cannot be produced...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..."
Note the key error: By saying that it "breaks" if any part is "missing" (i.e. taken away), it is only saying that evolution could not have reached that endpoint by successively only ADDING parts. True enough, but Behe misses the fact that you can also reach the same state by, say, adding 5 parts one at a time, and then taking away 2 which have become redundant. Let's say that part "A" does the job, but not well. But starting with just "A" serves the need. Then add "B", which improves the function of "A". Add "C" which helps A+B do their job, and so on until you have ABCDE, which does the job very well. Now, however, it may turn out that CDE alone does just fine (conceivably, even better than ABCDE does with A+B getting in the way of CDE's operation). So A and B fade away, leaving CDE. Note that CDE was built in "one change at a time" fashion, with each new change improving the operation. HOWEVER, by Behe's definition CDE is "Irreducibly Complex" and "could not have evolved (been built by single steps)" because removing C or D or E from CDE will "break" it. Note that Behe's conclusion is wrong. His logic is faulty.
The other error in Behe's definition lies in this part: "...any precursor to an irreducibly complex system, that is missing a part is by definition nonfunctional". The problem here is that it may be "nonfunctional" for its *current* function, but perfectly functional for some *other* function helpful for survival (and therefore selected by evolution). Behe implicitly claims that if it's not useful for its *current* function, it's useless for *any* function. The flaw in this should be obvious.
"Since natural selection can only choose systems that are already working, then if a biological system cannot be produced gradually it would have to arise as an integrated unit, in one fell swoop, for natural selection to have anything to act on."
True as far as it goes, but but this is hardly the same as Behe's sleight-of-hand in the first part of his statement, which relies on the false premise that a precursor to a structure is 100% useless for *any* purpose if *taking away* (but not adding) one part from the current purpose makes it unsuitable for the current purpose. Two gaping holes in that one...
Behe (an anathematized name)
For reasons I've outlined above.
talks of the bacterial flagellum, which contains an acid-powered rotary engine, a stator, O-rings, bushings, and a drive shaft. The machinery of this motor requires approximately fifty proteins.
Except that it doesn't. As many biochemists have pointed out, other organisms have function flagella (even *as* flagella) with fewer proteins (and/or different proteins). That flagellum isn't even "IC" by Behe's own definition since you *can* remove proteins and have it still work as a flagellum. [...]
For a far more realistic look at the evolutionary "invention" of the flagellum, see Evolution in (Brownian) space: a model for the origin of the bacterial flagellum , which I linked earlier in this post. From the abstract:The model consists of six major stages: export apparatus, secretion system, adhesion system, pilus, undirected motility, and taxis-enabled motility. The selectability of each stage is documented using analogies with present-day systems. Conclusions include: (1) There is a strong possibility, previously unrecognized, of further homologies between the type III export apparatus and F1F0-ATP synthetase. (2) Much of the flagellums complexity evolved after crude motility was in place, via internal gene duplications and subfunctionalization. (3) Only one major system-level change of function, and four minor shifts of function, need be invoked to explain the origin of the flagellum; this involves five subsystem-level cooption events. (4) The transition between each stage is bridgeable by the evolution of a single new binding site, coupling two pre-existing subsystems, followed by coevolutionary optimization of components. Therefore, like the eye contemplated by Darwin, careful analysis shows that there are no major obstacles to gradual evolution of the flagellum.Now *that's* science. Behe's stuff is just hand-waving and ivory-tower blowhardedness.
The fatal flaws in Behe's argument were recognized as soon as his book was published, and countless reviewers pointed them out. And yet, creationists and IDers, who seem to rely mostly on the echo-chamber of their own clique and appear to seldom read much *actual* scientific sources, still seem blissfully unaware of the problems with Behe's thesis, and keep popping in on a regular basis to wave the book around and smugly yell something like, "See, evolution has already been disproven!"
For an analysis of numerous errors and such in Dembski's Design arguments/examples, see Not a Free Lunch But a Box of Chocolates: A critique of William Dembski's book No Free Lunch. It also contains material on the flagella issue you raise next.
As for Behe (the other author):
One small example is the flagella on a paramecium. They need four distinct proteins to work.
Actually they need a lot more than that. And as far as I know, Behe never used the cilia on paramecia as his example, he has primarily concentrated on bacterial flagella.
They cannot have evolved from a flagella that need three.
Contrary to creationist claims (or Behe's) that flagella are Irreducibly Complex and can not function at all if any part or protein is removed, in fact a) there are many, many varieties of flagella on various species of single-celled organisms, some with more or fewer parts/proteins than others. So it's clearly inaccurate to make a blanket claim that "flagella" in general contain no irreplacable parts. Even Behe admits that a working flagella can be reduced to a working cilia, which undercuts his entire "Irreducibly Complex" example/claim right off the bat.
For a semi-technical discussion of how flagella are *not* IC, because many of their parts can be eliminated without totally breaking their locomotive ability, see Evolution of the Bacterial Flagella
But even if one could identify, say, four specific proteins (or other components) which were critically necessary for the functioning of all flagellar structures (and good luck: there are three unrelated classes of organisms with flagella built on three independent methods: eubacterial flagella, archebacterial flagella, and eukaryote flagella -- see Faugy DM and Farrel K, (1999 Feb) A twisted tale: the origin and evolution of motility and chemotaxis in prokaryotes. Microbiology, 145, 279-280), Behe makes a fatal (and laughably elementary) error when he states that therefore they could not have arisen by evolution. Even first-year students of evolutionary biology know that quite often evolved structures are built from parts that WERE NOT ORIGINALLY EVOLVED FOR THEIR CURRENT APPLICATION, as Behe naively assumes (or tries to imply).
Okay, fine, so even if you can prove that a flagellum needs 4 certain proteins to function, and would not function AS A FLAGELLUM with only 3, that's absolutely no problem for evolutionary biology, since it may well have evolved from *something else* which used those 3 proteins to successfully function, and only became useful as a method of locomotion when evolution chanced upon the addition of the 4th protein. Biology is chock-full of systems cobbled together from combinations of other components, or made via one addition to an existing system which then fortuitously allows it to perform a new function.
And, lo and behold, it turns out that the "base and pivot" of the bacterial flagella, along with part of the "stalk", is virtually identical to the bacterial Type III Secretory Structure (TTSS). So despite Behe's claim that flagella must be IC because (he says) there's no use for half a flagella, in fact there is indeed such a use. And this utterly devastates Behe's argument, in several different ways. Explaining way in detail would take quite some time, but it turns out that someone has already written an excellent essay on that exact thing, which I strongly encourage you to read: The Flagellum Unspun: The Collapse of "Irreducible Complexity" .
(Note: Several times that essay makes a reference to the "argument from ignorance", with the assumption that the reader is already familiar with it. I'd like to point out that contrary to the way it sounds, Miller is *not* accusing Behe et all of being ignorant. Instead, he's referring to this family of logical fallacies, also known as the "argument from incredulity".)
That is called irreducible complexity.
That's what Behe likes to call it, yes. But the flagella is provably *not* IC. Oops for Behe. Furthermore, while it's certainly easy to *call* something or another "Irreducibly Complex", proving that it actually *is* is another matter entirely.
As the "Flagellum Unspun" article above states:According to Dembski, the detection of "design" requires that an object display complexity that could not be produced by what he calls "natural causes." In order to do that, one must first examine all of the possibilities by which an object, like the flagellum, might have been generated naturally. Dembski and Behe, of course, come to the conclusion that there are no such natural causes. But how did they determine that? What is the scientific method used to support such a conclusion? Could it be that their assertions of the lack of natural causes simply amount to an unsupported personal belief? Suppose that there are such causes, but they simply happened not to think of them? Dembski actually seems to realize that this is a serious problem. He writes: "Now it can happen that we may not know enough to determine all the relevant chance hypotheses [which here, as noted above, means all relevant natural processes (hvt)]. Alternatively, we might think we know the relevant chance hypotheses, but later discover that we missed a crucial one. In the one case a design inference could not even get going; in the other, it would be mistaken" (Dembski 2002, 123 (note 80)).For more bodyblows against the notion of Irreducible Complexity, see:
What's funny is that by Behe's own argument, a stone arch is "irreducibly complex" because it could not have formed by nature *adding* sections of stone at a time (it would have fallen down unless the entire span was already in place -- and indeed will fall down if you take part of the span away):
Needless to say, what Behe's argument is missing in the case of the stone arch is that such arches form easily by natural means when successive layers of sedimentary rock added on top of each other, and *then* erosion carves a hole out from *under* the arch by *removing* material after the "bridge" of the arch itself *was already there*.
Similarly, Behe's arguments about why certain types of biological structures "could not" have evolved fall flat because he doesn't realize that evolution does not only craft features by *adding* components, it also does so by *lateral alteration*, and by *removing* components.
Behe's "irreducible complexity" argument is fatally flawed. It only "proves" that a *simplified* version of evolution (as envisioned by Behe) couldn't give rise to certain structures -- not that the *actual* processes of evolution could not.
"The question is," said Alice, "whether you can make words mean so many different things."
"The question is," said Humpty Dumpty, "which is to be the master -- that's all"
I've been posting this link and others saying the same thing for maybe the last five years on FR. Doesn't matter.
The first thing you need to understand about Behe's argument is that it's just plain wrong...ID is a shopworn bag of thoroughly refuted "Back Again Dumb As A Stump"-isms. It's transparently dishonest to keep coming back with such discredited material. What bugs me about ID is not that it's wrong, but that it's a lie.
Behe's colossal mistake is that, in rejecting these possibilities, he concludes that no Darwinian solution remains. But one does. It is this: An irreducibly complex system can be built gradually by adding parts that, while initially just advantageous, becomebecause of later changesessential. The logic is very simple. Some part (A) initially does some job (and not very well, perhaps). Another part (B) later gets added because it helps A. This new part isn't essential, it merely improves things. But later on, A (or something else) may change in such a way that B now becomes indispensable. This process continues as further parts get folded into the system. And at the end of the day, many parts may all be required.
The point is there's no guarantee that improvements will remain mere improvements. Indeed because later changes build on previous ones, there's every reason to think that earlier refinements might become necessary. The transformation of air bladders into lungs that allowed animals to breathe atmospheric oxygen was initially just advantageous: such beasts could explore open nicheslike dry landthat were unavailable to their lung-less peers. But as evolution built on this adaptation (modifying limbs for walking, for instance), we grew thoroughly terrestrial and lungs, consequently, are no longer luxuriesthey are essential. The punch line is, I think, obvious: although this process is thoroughly Darwinian, we are often left with a system that is irreducibly complex. I'm afraid there's no room for compromise here: Behe's key claim that all the components of an irreducibly complex system "have to be there from the beginning" is dead wrong.
It's worth noting that our scenario is neither hypothetical nor confined to the often irretrievable world of biological history. Indeed it's a common experience among computer programmers. Anyone who programs knows how easy it is to write yourself into a corner: a change one makes because it improves efficiency may become, after further changes, indispensable. Improvements might be made one line of code at a time and, at all stages, the program does its job. But, by the end, all the lines may be required. This programming analogy captures another important point: If I were to hand you the final program, it's entirely possible that you would not be able to reconstruct its historythat this line was added last and that, in a previous version, some other line sat between these two. Indeed, because the very act of revising a program has a way of wiping out clues to its history, it may be impossible to reconstruct the path taken. Similarly, we have no guarantee that we can reconstruct the history of a biochemical pathway. But even if we can't, its irreducible complexity cannot count against its gradual evolution any more than the irreducible complexity of a program doeswhich is to say, not at all.
I wish I could claim credit for this Darwinian model of irreducible complexity, but I'm afraid I've been scooped by eighty years. This scenario was first hinted at by the geneticist H. J. Muller in 1918 and worked out in some detail in 1939.6
oh, the by-line means what I think it does, then?
Google 'Reverend Moon Sekai Nippo'
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