Intelligent Design position statement
The Challenge of Irreducible Complexity
Every living cell contains many ultrasophisticated molecular machines.
By Michael J. Behe
Black box: a system whose inner workings are unknown.
Scientists use the term "black box" for a system whose inner workings are unknown. To Charles Darwin and his contemporaries, the living cell was a black box because its fundamental mechanisms were completely obscure. We now know that, far from being formed from a kind of simple, uniform protoplasm (as many nineteenth-century scientists believed), every living cell contains many ultrasophisticated molecular machines.
Does natural selection account for complexity that exits at the molecular level?
How can we decide whether Darwinian natural selection can account for the amazing complexity that exists at the molecular level? Darwin himself set the standard when he acknowledged, "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."
Irreducibly complex systems: systems that seem very difficult to form by successive modifications.
Some systems seem very difficult to form by such successive modifications -- I call them irreducibly complex. An everyday example of an irreducibly complex system is the humble mousetrap. It consists of (1) a flat wooden platform or base; (2) a metal hammer, which crushes the mouse; (3) a spring with extended ends to power the hammer; (4) a catch that releases the spring; and (5) a metal bar that connects to the catch and holds the hammer back. You can't catch a mouse with just a platform, then add a spring and catch a few more mice, then add a holding bar and catch a few more. All the pieces have to be in place before you catch any mice.
Natural selection can only choose among systems that are already working so irreducibly complex biological systems pose a powerful challenge to Darwinian theory.
Irreducibly complex systems appear very unlikely to be produced by numerous, successive, slight modifications of prior systems, because any precursor that was missing a crucial part could not function. Natural selection can only choose among systems that are already working, so the existence in nature of irreducibly complex biological systems poses a powerful challenge to Darwinian theory. We frequently observe such systems in cell organelles, in which the removal of one element would cause the whole system to cease functioning. The flagella of bacteria are a good example. They are outboard motors that bacterial cells can use for self-propulsion. They have a long, whiplike propeller that is rotated by a molecular motor. The propeller is attached to the motor by a universal joint. The motor is held in place by proteins that act as a stator. Other proteins act as bushing material to allow the driveshaft to penetrate the bacterial membrane. Dozens of different kinds of proteins are necessary for a working flagellum. In the absence of almost any of them, the flagellum does not work or cannot even be built by the cell.
Constant, regulated traffic flow in cells is an example of a complex, irreducible system.
Another example of irreducible complexity is the system that allows proteins to reach the appropriate subcellular compartments. In the eukaryotic cell there are a number of places where specialized tasks, such as digestion of nutrients and excretion of wastes, take place. Proteins are synthesized outside these compartments and can reach their proper destinations only with the help of "signal" chemicals that turn other reactions on and off at the appropriate times. This constant, regulated traffic flow in the cell comprises another remarkably complex, irreducible system. All parts must function in synchrony or the system breaks down. Still another example is the exquisitely coordinated mechanism that causes blood to clot.
Molecular machines are designed.
Biochemistry textbooks and journal articles describe the workings of some of the many living molecular machines within our cells, but they offer very little information about how these systems supposedly evolved by natural selection. Many scientists frankly admit their bewilderment about how they may have originated, but refuse to entertain the obvious hypothesis: that perhaps molecular machines appear to look designed because they really are designed.
Advances in science provide new reasons for recognizing design.
I am hopeful that the scientific community will eventually admit the possibility of intelligent design, even if that acceptance is discreet and muted. My reason for optimism is the advance of science itself, which almost every day uncovers new intricacies in nature, fresh reasons for recognizing the design inherent in life and the universe.
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Evolution response to Michael J. Behe
The Flaw in the Mousetrap
Intelligent design fails the biochemistry test.
By Kenneth R. Miller
Michael J. Behe fails to provide biochemical evidence for intelligent design.
To understand why the scientific community has been unimpressed by attempts to resurrect the so-called argument from design, one need look no further than Michael J. Behe's own essay. He argues that complex biochemical systems could not possibly have been produced by evolution because they possess a quality he calls irreducible complexity. Just like mousetraps, these systems cannot function unless each of their parts is in place. Since "natural selection can only choose among systems that are already working," there is no way that Darwinian mechanisms could have fashioned the complex systems found in living cells. And if such systems could not have evolved, they must have been designed. That is the totality of the biochemical "evidence" for intelligent design.
Parts of a supposedly irreducibly complex machine may have different, but still useful, functions.
Ironically, Behe's own example, the mousetrap, shows what's wrong with this idea. Take away two parts (the catch and the metal bar), and you may not have a mousetrap but you do have a three-part machine that makes a fully functional tie clip or paper clip. Take away the spring, and you have a two-part key chain. The catch of some mousetraps could be used as a fishhook, and the wooden base as a paperweight; useful applications of other parts include everything from toothpicks to nutcrackers and clipboard holders. The point, which science has long understood, is that bits and pieces of supposedly irreducibly complex machines may have different -- but still useful -- functions.
Evolution produces complex biochemical machines.
Behe's contention that each and every piece of a machine, mechanical or biochemical, must be assembled in its final form before anything useful can emerge is just plain wrong. Evolution produces complex biochemical machines by copying, modifying, and combining proteins previously used for other functions. Looking for examples? The systems in Behe's essay will do just fine.
Natural selection favors an organism's parts for different functions.
He writes that in the absence of "almost any" of its parts, the bacterial flagellum "does not work." But guess what? A small group of proteins from the flagellum does work without the rest of the machine -- it's used by many bacteria as a device for injecting poisons into other cells. Although the function performed by this small part when working alone is different, it nonetheless can be favored by natural selection.
The blood clotting system is an example of evolution.
The key proteins that clot blood fit this pattern, too. They're actually modified versions of proteins used in the digestive system. The elegant work of Russell Doolittle has shown how evolution duplicated, retargeted, and modified these proteins to produce the vertebrate blood-clotting system.
Working researchers see evolution in subcellular systems.
And Behe may throw up his hands and say that he cannot imagine how the components that move proteins between subcellular compartments could have evolved, but scientists actually working on such systems completely disagree. In a 1998 article in the journal Cell, a group led by James Rothman, of the Sloan-Kettering Institute, described the remarkable simplicity and uniformity of these mechanisms. They also noted that these mechanisms "suggest in a natural way how the many and diverse compartments in eukaryotic cells could have evolved in the first place." Working researchers, it seems, see something very different from what Behe sees in these systems -- they see evolution.
Behe's points are philosophical, not scientific.
If Behe wishes to suggest that the intricacies of nature, life, and the universe reveal a world of meaning and purpose consistent with a divine intelligence, his point is philosophical, not scientific. It is a philosophical point of view, incidentally, that I share. However, to support that view, one should not find it necessary to pretend that we know less than we really do about the evolution of living systems. In the final analysis, the biochemical hypothesis of intelligent design fails not because the scientific community is closed to it but rather for the most basic of reasons -- because it is overwhelmingly contradicted by the scientific evidence.
Originally posted by josephwI didn't get past that sentence. It is false. Scientists use the term "black box" for a system whose inner workings are irrelevant to the problem being investigated.
Scientists use the term "black box" for a system whose inner workings are unknown.
See:
http://en.wikipedia.org/wiki/Black_box
Michael Behe is a joke in the scientific community following his humiliation in the Tammy Kitzmiller v. Dover Area School District court case.
In his summary the judge made the following comments about Behe's testimony:
"We therefore find that Professor Behe's claim for irreducible complexity has been refuted in peer-reviewed research papers and has been rejected by the scientific community at large"
"Professor Behe’s concept of irreducible complexity depends on ignoring ways in which evolution is known to occur. Although Professor Behe is adamant in his definition of irreducible complexity when he says a precursor “missing a part is by definition nonfunctional,” what he obviously means is that it will not function in the same way the system functions when all the parts are present. For example in the case of the bacterial flagellum, removal of a part may prevent it from acting as a rotary motor. However, Professor Behe excludes, by definition, the possibility that a precursor to the bacterial flagellum functioned not as a rotary motor, but in some other way, for example as a secretory system"
"Professor Behe has applied the concept of irreducible complexity to only a few select systems: (1) the bacterial flagellum; (2) the blood-clotting cascade; and (3) the immune system. Contrary to Professor Behe’s assertions with respect to these few biochemical systems among the myriad existing in nature, however, Dr. Miller presented evidence, based upon peer-reviewed studies, that they are not in fact irreducibly complex."
His own colleagues at Lehigh University think him a fool - they have publicly distanced themselves for his Intelligent Design and Michael Behe.
The meta story behind Behe is telling: A Christian becomes a biology scientist and then discovers that science conflicts with his supernatural belief structures – He concocts a cover story that is un-provable and un-testable. He backs his cover story with NO peer review, yet still claims it is science. He does not speak up until after he cannot be fired – he stands alone defending theory-that-is-not-a-theory against the scientific community while claiming to be a intellectual revolutionary fighting against the establishment.
Originally posted by FeastboySorry mate, but evolution still remains an unproven theory and it is not correct to ask for an unproven theory to be disproved.
It's untestable sure but if someone were to dis-prove evolution then it would gain credibility from that despite not being tested itself. Thankfully I doubt very much if that will happen. 🙂
Microevolution exists, biologists who study evolution at this level define evolution as a change in gene frequency within a population. It’s fairly easy to decide what a population is. It is a group of organisms that interbreed with each other—that is, they all share a gene pool, ie: insects develop resistance to pesticides, humans are taller, etc..
However, when "evolution" is referenced, without doubt it is macroevolution, or Darwinism, that is being discussed.
Macroevolution refers to evolution above the species level. Macroevolution encompasses the grandest trends and transformations in evolution much beyond mutation, such as the origin of mammals. There are no firsthand accounts to be seen. During 149 years since the publishing of Origin of Species, study of the history of life using all available evidence: geology, fossils, and living organisms, there still has not appeared evidence of linkage between species to prove Darwins theory.
Originally posted by MacSwainWhat a load of trash. There is heaps of evidence. You ever heard of fossils.
Sorry mate, but evolution still remains an unproven theory and it is not correct to ask for an unproven theory to be disproved.
Microevolution exists, biologists who study evolution at this level define evolution as a change in gene frequency within a population. It’s fairly easy to decide what a population is. It is a group of organisms that interbre ...[text shortened]... sms, there still has not appeared evidence of linkage between species to prove Darwins theory.
Originally posted by scottishinnzOf course I have. Please point out a fossil (link) which shows one species becoming another. Sorry mate, it does not exist at this point. When, and if, one is found it will be earth shaking news and you and I will not have to do any "digging" (pardon the pun) to hear about it.
What a load of trash. There is heaps of evidence. You ever heard of fossils.
Originally posted by MacSwainThat's simply a strawman you are attempting to set up. However, we have whole lineages of organisms catalogued, for example the evolution of birds from reptiles, or the evolution of whales. We have cladistic analysis of both nuclear and mitochondrial (and in plants chloroplastidic) DNA which is ALL concurrent with the theory (a word you seem to be unaware the meaning of). We have hypothesis after hypothesis posited by the theory of evolution being proven correct.
Of course I have. Please point out a fossil (link) which shows one species becoming another. Sorry mate, it does not exist at this point. When, and if, one is found it will be earth shaking news and you and I will not have to do any "digging" (pardon the pun) to hear about it.
Multiple lines of independent, yet complementary, evidence all pointing to the same, irrefutable conclusion.
Originally posted by scottishinnzEvery school boy has seen photos of fossils of winged reptiles...and this only proves that at a time in earths history reptiles had appendages necessary for flight. There is no fossil evidence demonstrating they became birds. Again, no link exists.
That's simply a strawman you are attempting to set up. However, we have whole lineages of organisms catalogued, for example the evolution of birds from reptiles, or the evolution of whales. We have cladistic analysis of both nuclear and mitochondrial (and in plants chloroplastidic) DNA which is ALL concurrent with the theory (a word you seem to be una ...[text shortened]... s of independent, yet complementary, evidence all pointing to the same, irrefutable conclusion.
Originally posted by MacSwainIt won't be earthshaking news because we have tons of those. All fossil forms are transitional in that way; it's just that the transitional organisms are also species unto themselves. In human evolution we might look at any two of our ancestors, at different points on the line - say, australopethicus and early homo sapiens. Then we have, right between them in the fossil record, a transitional form showing aspects of these two species in flux. Of course, that form - homo habilis - is also a species unto itself, in the same way that australopithecus, the species, was transitional between ardipithecus and homo habilis. It's not that we don't have any fossils that show transition; they all show that. But the fact that they're in-between doesn't mean they're not also species in their own right.
Of course I have. Please point out a fossil (link) which shows one species becoming another. Sorry mate, it does not exist at this point. When, and if, one is found it will be earth shaking news and you and I will not have to do any "digging" (pardon the pun) to hear about it.
What you have to understand is that in nature the process of evolutionary change is constant, though very slow. Over the few thousand years since we've been studying complex organisms there isn't much noticeable change. But in evolutionary terms, what we call species are really just snapshots of different points on an incredibly long timeline. The change is actually gradual, and very slow, and it has no distinct lines between one species and another; it only seems to because we're looking at different points millions of years apart. So whenever we find remains of an organism we hadn't previously discovered, we note how it shows the transition between other forms we already know about, but we also give it its own species name. There aren't any organisms that are "just" transitional between two others, without being a species of their own. All species are transitional.