Darwin’s theory- the survival of the fittest and most adaptable, originally was used to explain the evolution of species of animals but since then it has been used to explain human behavior, and the origin of the cell. Knowledge of biochemistry has made remarkable gains since the time of Darwin. “Molecular machines raise an as yet impenetrable barrier to Darwin’s universal reach.”
“The complexity of life’s foundation has paralyzed science’s attempt to account for it; it is now known that biological molecules make up machines. Each machine has a specialized use. The question which Behe asks is: can the existence of these machines be explained by random mutations/natural selection?
As an historical background Behe gives a series of examples from the past where science went as far as it could go until new equipment allowed further investigation. This led to correction or abandonment of old ideas and new understanding took their place. He calls this a series of black boxes. As one was opened this revealed another black box which could not be opened until new equipment came along. Aristotle was very observant and brilliant in his assessment but his observations could only go so far. Leeuwenhoek invented the microscope- it opened up a world which was far more complex than anyone imagined. Crystallography allowed us to see proteins. This and other tools allowed biochemists to see the bedrock of cells. The last block was now open to investigation. It is this complexity of the cell which has called Darwin into question as far as life’s foundation is concerned.
Darwin was never able to explain how a nerve became sensitive to light and how this led to the development of the eye. Not because he was stupid but because the kind of details now known equipment of his age did not allow.
Mr. Behe explains in simplified form the manner in which light enters the eye and triggers a series of responses which allows us to see. This process requires a molecular explanation . A photon of light hits a protein. This sets off a set of chain reactions. Each one dependent upon coordination with other proteins. All of which work together in a very set order. There is also another set of reactions which are triggered by the photon of light to continue to make the proteins necessary to keep seeing. The anatomy of the eye available to Darwin was insufficient to understand the set of proteins necessary to allow us to see. In fact the anatomy of the eye obscures the complexity with which the eye works. Biochemistry has unlocked this black box.
Mr. Behe asserts that for Darwin to be true, his theory must account for the molecular basis of life.
It appears that Michael Behe is not the only one offering challenges to Darwin’s theory. Lynn Margulis asks those who support Darwin’s theory to name one new species formed by accumulated mutations. In paleontology digs, dramatic jumps are often shown in the development of a species. Mathematicians question the time frame required for Darwin’s theory to explain the development of the eye. One mathematician, Hubert Yockey suggests that life is a given like matter.
Complexity theory offers problems for Darwinists. This theory suggests that many features of a living system are the result of self-organizing to arrange themselves in patterns not natural selection.
Behe suggests that the reason these views have been ignored: scientists worry about giving ammo to creationists- thus in the guise of protecting science, criticism of natural selection has been brushed aside.
Too many scientists take Darwin as dogma, instead of as a theory which may need correction.
As an example Behe cites the eye. He insists that the complexity of the eye can not be explained by adding one complex system to another. The problem with all of this is that Darwin’s theory requires a slow steady development. If any development is rapid- this implies a miracle- for which there is no scientific explanation.
But irreducibly complex biological systems are a challenge to Darwinists. Why? As complexity increases the likelihood of chance development drops a whole bunch. Now a scientist could appeal to brute luck- this of course can not be refuted but luck wanders into the realm metaphysics. The difficulty lies in gradualness in development- without it one must turn to miracles. Why?
It lies in the nature of mutation. Single mutations usually make small change. But a single mutation cannot change all of the instructions in one step. Evaluating Darwin’s theory can not be done by examining the eye as a unit but it can be done by examining discrete molecular systems.
The easy example Behe gives for irreducible complexity is a mouse trap. All parts must be present for it to work. All parts must also be of the correct material to support the needs of each part. He also discusses that Darwin’s theory requires physical precursors. A bicycle can not become a motorcycle. It is a conceptual precursor. It is not a physical precursor. Minimal function is also required for Darwinism.
Chapter 3
A cell is operated by molecule machines. These molecules are mostly made up of proteins. Proteins carry out chemical reactions. They are very versatile but usually have one use or at most a few. Thus each cell has thousands of proteins.
There can be anywhere from 50 to 1,000 proteins in a chain. These chains vary in length and each link has different properties. Some have negative charge, some positive, some are small and some large. Their shapes are turgid. Thus if two proteins are to join together, they must fit. If they do not properly fit, they will not function.
Let us look at a molecular machine which allows a one celled animal to swim. This device is called a cilium. What is needed to swim constitutes an irreducibly complex system. This means that if any protein is removed, the cell can not swim. All aspects of stuff required to swim must match. One more thing is needed- timing of the working parts and direction.
Can this system have developed gradually?
Each part of a cilium must fit exactly with its neighbor for the cilium to function. “The complexity of the cilium and other swimming systems is inherent in the task itself. “ It is irreducibly complex. It appears that it came as a unit. This fact contradicts Darwin’s gradual development.
Dawkins, a Darwinist, suggests that the evolution of the cilium occurred this way. At some time microtubules (these support motor cells, commonly occur, transport cargo travel along these) stuck together. Later, motor proteins accidently acquired ability to push 2 microtubules. This caused a bending. It may have helped the cell survive. Continued small development gradually produced the cilium.
But Behe asks- how exactly? A protein which accidently stuck to microtubules would block use of this for travel. A protein which joins two microtubules would alter the shape. A fit can not be made if the shapes are not correctly matched.
Behe mentions that there are 10,000 papers published on the cilium. Only two deal vaguely with evolution. Both contradict each other. Both papers lack quantitative details, both papers hoped to prod others to work on the problem. This did not happen.
For the question of the evolution of the cilium to be answered, details must be supplied.
Cilia contain tubulin, dynein, nexin and numerous other proteins. If these are placed in a cell which does not have a cilium, these will not produce a functioning cilium. More is needed than the presence of the parts for the whole to be made. Cilium has 200 plus different proteins. As the number of parts increases the likelihood of gradual assembly drops.
Chapter 4
M. Behe uses a Rube Goldberg silly machine to make a point. All parts are essential. For change gradually to occur, while parts are rearranged or changed, it would cease to function. Darwin’s evolution tends to discard what does not function.
Behe writes about blood clotting. It is called a cascading system. This means that when bleeding occurs, this sets in motion a series of changes which stops the bleeding in the area of the bleeding only, it must also set in motion those steps which will bring a halt to the production of what causes the clotting or the organism will die. In other words the clotting and control of clotting must be tightly regulated.
For Darwin’s theory to explain the development of this, numerous successive, slight modifications must be found.
Russell Doolittle gives an explanation for the evolution of clotting. He presents a series of steps where clotting proteins appear, first one then another. The problem is that no reasons are given for the appearance of these proteins. He does not indicate where these proteins came from. He tends to use such words as: appear, is born, arise, spring forth.
Behe tackles the problem this way. Animals which have blood clotting cascades have 10,000 genes. Each gene has 3 parts. That makes 30,000 pieces. TPA which is a necessary part of blood clotting has 4 types which are part of the cascading system. The odds of getting these 4 together is 30,000 to the fourth. Behe puts this in lottery terms. If 1,000,000 people played each year- it would take 1,000 billion years for anyone to win. 1,000 billion years is 100 times the known age of the universe. Doolittle’s solution presents huge difficulties.
Irreducibly complex systems are the main difficulty. As Doolittle’s system goes, as the system began to assemble, when there was nothing to do. Proteins would be combining for no purpose, no reason. If such a protein appeared with no function, evolution would tend to get rid of it.
Chapter 5/6
Each cell has speciality areas separated off for specific tasks: nucleus, mitochondria, endoplasm reticulum, secretory vesicles, golgi apparatus, lysosome, perorisome. Each is kept separated by a membrane, each membrane is separated because these are made up of material not found in the other parts of the cell.
Manufactured material which the cells needs to function travels a grand distance of 1/10,000 of an inch on its journey from the cytoplasm to the lysosome, yet it requires the service of dozens of different proteins to assure its safe arrival.
This system is irreducible and the system by which it moves from one area to another is itself also irreducibly complex.
This movement from one area to another is called a gated transport system. How does this gated system work? Proteins contain a signal recognized by the membrane inside the cell. A protein channel opens and the protein passes through. This system poses a major challenge to Darwinian evolution. Without a signal a protein would not be recognized. If a protein did not exist to recognize the signal there would be no transport. If the portal allowed all proteins to pass- this compartment would be no different than any other part of the cell.
Vesicular transport is even more complex. Behe uses this model. His model is that of an automated car transport system. Cars enter a truck. Truck enters a garage. Cars unload, and park. Must have six components to do this. There must be a tag on each car, a truck, a truck scanner, identification tag for the truck, a scanner at the garage and at the gate. There are in this system more parts. Gated transport and vesicular transport systems which depend upon a precise set of proteins arranged in a specific way. Gradual development in Behe’s opinion is impossible. The two systems are so different, so complex that there seems to be no way to make the case that one evolved from the other. Plus for the transportation system to work, the whole system must be present.
Incremental change simply can not account for these systems.
The complexity of these systems would have required chance for the system to develop. Whence came chance? How many times can chance be used to explain? What are the odds that chance, time and again brought about a system so complex and irreducible?
Michael Behe now discusses antibodies. There are 100,000 different antibodies. The antibody molecule is made inside a cell. For the antibody to attack an invader it must have a binding site which matches that of the invader it attacks. The antibody is attached to a cell which made it. These travel about. When bacteria is encountered, the antibody attacks the bacteria and brings it inside the cell. The foreign protein is chopped up, a piece sticks to the cell’s MHC protein. This protein goes to the surface. A T cell comes along, and binds to the B cell which made the antibody. If the T cell fits, it releases interleukin- this ends a message to the B cell- GROW. It begins to reproduce. T cells keep secreting interleukin. B cells produce spin off cells, plasma cells. These produce antibodies which float freely about.
Darwinian steps will not meet the needs to explain this, says Behe. There is no sequential way by a series of steps for this development to occur.
Scientists conducted the following experiment: created molecules out of proteins, these molecules do not occur in nature, injected these into a rabbit. The rabbit proceeded to make antibodies which attached to the molecules. How could the cells of the rabbit make antibodies for an intruder it had never seen before? Answer: inherited DNA can be altered.
Antibodies do not kill the invader- these antibodies serve as signals to other systems to kill the invader. A complement system to the antibodies, via a series of very complicated steps, punctures the enemy, causing it to take in water and explode.
Along with this the reader must realize that these cells know not to attack say red blood cells. These two systems must be present from the beginning of the immune system.
Chapter 7
What would it take in Darwin’s theory for these proteins to join together for these complex systems? Behe uses the ground hog crossing a road to get to its lover. The highway has 2,000 lanes. None reach their destination. Illustrates problems of gradual evolution.
Proteins are strung like beads. For example AMP has 10 carbon atoms, 11 hydrogen atoms, 7 oxygen, 4 nitrogen and 1 phosphorus. The formation of the nucleotide AMP involves the coming together of carbon, hydrogen, oxygen, nitrogen and phosphorus atoms via a series of very complex steps which require the intervention of other molecules to make sure that the final stage is achieved. AMP occurs via 13 steps requiring 12 enzymes and energy molecules. The energy must also be supplied at the correct times, just when the energy is needed. So far no one has been able to explain how the steps to produce AMP cold have happened. Actually the problem is even more complex than this. None of the above accounts for the fact that there must be something to turn on its production and turn it off.
The production of AMP offers stiff challenge to gradual development. The obstacle has yet to be addressed.
Irreducibly complex systems offer severe problems for gradual development. But even the development of a building block presents major difficulties.
Chapter 8
Nearly all 20 of the amino acids have been produced in labs. This has been used to explain that life happened because of the presence of the material here on earth which make up amino acids. Behe points out that this has only happened in the lab. For amino acids to form a protein, a molecule of water must be removed from each amino. But water was abundant on earth and aminos dissolve in water. Other theories have been suggested- amino tossed on the edge of a volcano- this kept excess water away. But studies have shown that this does not produce proteins. Much can be done in the lab but only under very controlled conditions.
Darwin’s theory explains the development of a hippo but it does not explain the origin of life. In a way part of Behe’s argument against Darwin’s theory is that it is so heavily believed because that is simply what people have been taught and have accepted it uncritically. I think that an additional concern is that Darwin’s theory has been applied to areas of study of which he knew nothing. It has been treated as the universal explanation.
Michael Behe then has a very interesting discussion of biochemical texts. These simply do not address the issue. The writers of the texts seem to have difficulty in admitting that problems exist in using Darwin to explain these complex systems and how they developed. He gives an example of a text which has 6,000 citations. 2 concern evolution. In his view without proof,, without discussion, or debate, Darwin’s theory is simply accepted. This same text revised in 1982, citations increased to 7,000 with only two concerning evolution. A comment on the subject goes like this in the book: Sperm whales have several tons of oil in their heads. This oil thickens as the whale dives allowing it to swim more easily. “Thus we see in the sperm whale a remarkable anatomical and biochemical adaptation, perfected by evolution.” No discussion, no evidence precedes the statement, no proof after. If this is how texts deal with the problem how do biochemists know what they know about the subject?
Chapter 9/10
Darwinism does not offer an explanation here. Others have stepped in: Cell parts were once free living organisms, as time passed one organism swallowed another. Another theory: complexity theory- “systems with large number of interacting components spontaneously organized themselves into an ordered pattern.” Another theory is Intelligent Design. This is the purposeful arrangement of parts. I think that Behe has come to this conclusion because too much of Darwin relies on chance. Makes it kind of an easy argument to maintain but not very scholarly or scientific.
The more complex the system, the more likely it was designed. Who the designer is can not be determined by the system itself. Behe cautions- “Just because we can infer that some biochemical systems were designed, does not mean that all subcellular systems were explicitly designed.”
William Paley once asked how something complex in nature could be produced without a designer. He views are ignored in modern times but no one has ever refuted this statement.
Behe suggests that the ordering of separate components to accomplish a function beyond that of the individual components is an argument for intelligent design.
Some have used flawed structures as an argument against intelligent design. Behe’s reply: perhaps we have not yet figured out what use it may have. He also suggests that it is not the role of science to make assumptions of how things ought to be. I.D. also does not mean that life was recent- nothing to prevent it from being billions of years old. And he adds that mutation and natural selection are compatible with I.D.
I.D. also offers a challenge to a field which has become stagnant and in need of a jolt to get people to think and discuss from divergent views. He hopes that his ideas prompt new research.
It is interesting to me that science appears to have uncovered something which can not be explained by what we now know or think to be true.
Reluctance to grapple with Behe’s ideas he lays at the door of chauvinism- scientists feel that they alone can explain the physical world. And he lays it at the door of history. The war began long ago he suggests with the famous debate between Huxley and Wilberforce. Huxley defended Darwinism and Wilberforce, religion. Science thinks itself separate from philosophy. Yet books published by scientists on the subject of evolution are very philosophical. Many assertions are made in these books which are not supported by tests made in a lab.
Behe even goes so far as to ask where is it written that the supernatural must not be part of science.
Test tube testing of the existence of dinosaurs can not be done- but it is still a science.
Behe suggests that scientists should follow the physical evidence wherever it leads, with no artificial restrictions.
Some scientists try to put science in a tidy box. This encourages timidity. Some scientists have an a priori view of what philosophical views they should have. I have seen this in some scholarship I have studied concerning Classical Latin and ancient Rome.
He cites that many accept the Big Bang theory. Yet, it postulates a very abrupt beginning. This theory is very friendly to religion. Hoyle for that reason rejected the Big Bang and instead suggested that the density of the universe was due to one hydrogen atom coming into existence per cubic mile of space. He seemed to ignore that his idea suggested the creation of something from nothing. Crick, the famous Crick, thinks that aliens brought life to earth. He reasons that life is so complex that it seems impossible that life happened without direction. But by asserting that aliens brought life to earth, he postpones for a moment to explain where they aliens came from.
“Intolerance does not come about when someone thinks that they have found a truth but when that someone believes that all should agree. The following scientists serves as an example. Maddox, a scientist, said that religious believers are like wild animals in need of a cage.
The philosophical argument that science should avoid theories which smack of the supernatural is an artificial restriction on science.
My view is that of Symmachus- no one can arrive at truth by one path only.
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