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An Answer to Dr. Geisler—From the Perspective of Biology
To most of us in science, the two-century old views of William Paley seem quaint, but we forget just how many people have been left behind on this subject. In fact, so many have been left behind on both the vitalism versus mechanism and the creation versus evolution controversies that we even find non-creationists reaching conclusions similar to those of the creationists regarding the origin of life. Geisler cited two such people who are well-known in creationist-anticreationist circles: the Hoyle and Wickramasinghe (1982) team for one and Hubert Yockey (1977, 1981) for the other.
Yockey seems to have achieved his fame by being frequently quoted by creationists, yet, so far as I know, he is not a religiously motivated creationist himself. I agree with others who say that his probability calculations are "shot through with errors" (Doolittle, 1983). However, his appeal for scientific skepticism is welcome. As for Hoyle and Wickramasinghe, neither accepts the creation "model," though the latter witnessed in defense of the Arkansas creationism law. Regardless of the general lack of sympathy these people seem to have for the complete creationist position, they have supplied some of the major arguments creationists use. In this paper I'd like to explain where the creationists and their non-religious sympathizers seem to have erred concerning the question of design.
Randomized DNA is still DNA.
First let's take up the familiar "hurricane in a junk yard," "electric fan and alphabet cereal," and "monkeys at typewriters" examples, while at the same time paying attention to the relevant biochemistry. All these colorful images miss at least one crucially important point. Life very likely got its start with a very special chemical called RNA. RNA (ribonucleic acid) has all sorts of properties that we are just beginning to discover. A very recent finding showed that not only can RNA carry coded genetic information, but it also can carry out specific chemical reactions that were previously thought to be the exclusive domain of proteins (Lewin, 1982).
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Prior to this finding, origin-of-life theoreticians were faced with a chicken and egg type of problem. Present-day life uses nucleic acids, both RNA and its close relative DNA, to direct the synthesis of proteins. Some of these proteins are needed for both DNA and protein synthesis. The old puzzle was where the first proteins came from to help DNA and RNA direct protein synthesis. While a lot of work remains to be done in this new area, we now know that the question was naive. The claim that life couldn't have started with nucleic acids since they would have had no help from proteins seemed reasonable only until someone discovered that RNA can function as if it were a protein. That solved the problem.
Such impossibility arguments are awfully difficult to make in science because they depend so heavily on initial assumptions. It takes a rather arrogant person to claim that he has constructed an air-tight impossibility argument for something. Such a person says that he knows all the boundary conditions for a particular situation. I, for one, tend to go with the ideas of people who are willing to admit that we don't know everything. I know that origin-of-life scenarios get more and more detailed and plausible as each passing year brings more knowledge.
Another thing about nucleic acids that the "bull in the china shop" people tend to overlook is the almost infinite number of possible configurations a former china shop can take on compared to the far more limited number of sequences a damaged piece of DNA can acquire. The genetic code that DNA carries can change, but it is still DNA, whereas the destroyed china shop could take on almost any shape imaginable. The damaged DNA still has the same chemistry, the same beautiful symmetry, the same spiral staircase configuration, the same width from one side of the "staircase" to the other, the same base pairing across each rung of the staircase, the same phosphate—sugar—phosphate—sugar backbone in each strand, and the same lack of an oxygen molecule at the number two position of each and every sugar. A miracle? Well, no, not unless all chemistry is miraculous.
Now compare this with the "hurricane in the junk yard" or even Geisler's "alphabet cereal." Would the cereal land in neat rows with all the letters right side up? Is there an automatic process that would save any cereal word groups that made any sense at all? Would those word groups that made a little sense make copies of themselves? Would some of the copies have trivial errors, and would the automatic selection process save any copies that happened to say something new? Would the copies that had the most useful information replicate themselves faster than those that had less useful information? Since mutated (randomized) DNA is still DNA, and since DNA is capable of self-replication, DNA and its precursors yield a "yes answer to the forgoing questions, while the cereal example gives a "no."
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Another major problem with Geisler's alphabet cereal analogy is his insistence that an evolutionary goal be set up in advance. He says we would never get an encyclopedia. That's a very specific goal. Geisler implies that he wouldn't be impressed if we got a poem, a pretty design, or a phone book. Only an encyclopedia will do. Geisler's fatal error is that evolution does not work toward an ultimate goal, but is strictly opportunistic. Anything that helps ensure the continued replication of a self-replicating species is saved.
I'd like to illustrate how adding more chemically appropriate assumptions to the alphabet cereal example makes the idea of getting a book seem far more plausible. I must confess that I used Scrabble® letters rather than alphabet cereal. This was just a matter of convenience for me. The change shouldn't alter the probabilities very much. I put the randomized letters in a nice neat row, the way they would be in RNA or DNA. Finally I looked for any recognizable words. This is essentially what natural selection does with nucleic acids. Eigen and his colleagues (1981) have done a good job of explaining observations that have shown replicating nucleic acids responding directly to natural selection, so the supposition that this could happen is not just wishful thinking.
I found the word "copy" in the first seven Scrabble letters. Before I had fifty letters on the table the sentence "Get it." appeared. Overall I had found nine letters out of fifty that made up words. That's about ten percent.
Yockey and many creationists would probably calculate the probability of this happening in the following manner. There are nine uniquely specified letters with twenty-six letters to choose from at each of the nine positions; therefore the chance of finding "Copy. Get it." would be 1/26th to the ninth power, or about two chances out of ten trillion tries. Indeed, if I went looking for "Copy. Get it." or even another sentence with the same "information content" the next time I played this game, I might spend quite a while looking. On the other hand searching for any words is a much easier game. Evolution seems to work in a very similar manner.
Generally, we tend to think that the most intelligent animal has to be warm-blooded and hairy with a segmented backbone because that's the way things are. But how would we go about showing that this is the only way? If some new change is helpful, that's all that should matter. Why insist on solution "A" if solution "W/KJ37AGR" and an almost infinite number of similar solutions also work?
Alphabet cereal, junk yards, and other creationist analogies are very different entities from self-replicating systems. Geisler does mention the idea of Mt. Rushmore's directing the synthesis of new Mt. Rushmores (heaven help us!), but he doesn't begin to explore the ultimate ramifications of such a system were it to have the ability to mutate and respond to selection. Were this possible, Mt. Rushmore would constitute a new form of life. By the time all the natural cliffs in the world had been obliterated by this self-replicating monstrosity we might expect to see more than former presidents. Natural selection and random change would have left their marks on each new generation of Rushmores. If we were to find such a life form, it would certainly be a puzzle to biologists. For, unlike organic life, it would be far more difficult to postulate a natural origin for it.
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So, if after centuries of fruitless investigation we were unable to formulate a natural origin for this cliff-wrecker organism, we might be forced to postulate intelligent creation, perhaps by some misguided alien. But no legitimate scientist would postulate a supernatural origin for the cliff-wrecker since the notion would suggest no further research. A supernatural hypothesis in science is the ultimate form of an impossibility statement. It would say, in effect, "I can't find a natural cause for this observation, therefore no natural cause exists." Greater arrogance is difficult to imagine.
Natural selection has been shown to be creative.
All through Geisler's article he reasons that if something in life is interesting, complex, and/or apparently clever, one must conclude that it has been designed by some outside intelligence. Well, this isn't always true. I can't think of a better way to illustrate this than to cite a series of experiments conducted by Barry Hall at the University of Connecticut (1982). His work has centered on the evolution of a new gene complex in the common bacterium E. coli. He has taken a strain that has completely lost a gene and the associated genetic mechanism that regulates its activity. Starting with this defective strain he has utilized an environment that confers an extreme selective advantage to any bacterium able to reinvent, so to speak, the missing gene and its regulatory mechanism. Finally he has studied at the molecular level the "solutions" found by the bacterium. The newly evolved genes naturally have many features in common with each other, but they also show a considerable amount of creativity. Some solutions are elegant and some appear to be rather awkwardly complex. They all work, however. If complexity were a measure of design, we would have to say they were all designed. Yet we know the genes evolved in the laboratory. Barry Hall did not design the new genes no matter how much the creationists may wish to think that he did.
I can think of two creationist comebacks to Hall's work. One would say that E. coli must have been designed by a very clever creator to be able to evolve so well. Such a response really isn't too helpful to the creationist cause. The other reply would simply claim that the evolution of a single gene and some regulatory apparatus to go with it is trivial evolution "within" created kinds, and thus is of no real significance to the creation-evolution debate. They would say that the E. coli with the newly evolved genes are still E. coli and not a horse or a tiger. But if the evolution of new genes is trivial and expected by creationists, then all creationist arguments about entropy and probability are also trivial, since these supposedly prevent the evolution of new genes.
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Hall's articles are very heavy reading for non-biologists and even for many biologists. Perhaps that is the reason they have not been widely referenced in the creation-evolution context before this. Anyone who is going to claim impossibilities in the area of evolution at the molecular level should make a special point of reading and understanding just what Hall has observed with E. coli.
Determination of origins is not a look-and-know operation.
Geisler starts out his article with an elaborate explanation of how we know about the desecration of Mt. Rushmore. We are supposed to conclude that it was created, but in fact his criteria don't always work as well as he implies. Before his death Louis Leaky found what he said were human artifacts in the Western United States. There was little disagreement that the location of these "artifacts" made them older than any other aboriginal artifacts on this continent by many fold. But there still is disagreement as to whether they are in fact artifacts. In real life it isn't quite so easy to tell if a rock with a funny shape actually is an artifact.
Certainly almost every scenic spot in the world has some type of imagined sculptured object. I remember guided tours of a limestone cave near Madison, Wisconsin. In the cave were stone slabs of bacon, frying pans, faces, creatures, and what not. None of them showed the mark of the sculptor's chisel. In fact the cave had been carefully kept in its natural state since its discovery a few years before my well-supervised visits. The point is that it is sometimes difficult to tell, just by looking, whether something is in its natural state. Geisler's look-and-know tests are just not very powerful by themselves.
If we really want to know if something could have come to its present state through natural processes, we must try to find out if there are natural processes that are equal to the task. We would feel very confident in our "natural processes" conclusion if we found that these same processes are going on today. Of course we find that evolution fills the bill as an ongoing process, one capable of explaining the origins of both contemporary and fossil organisms. With this information in hand, we no longer have to rely on look-and-know approaches to uncovering "origins."
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Evidence of Design by Nature
It would be instructive at this point to briefly mention some of the major design arguments for evolution. There is a tremendous body of evidence that points to an evolutionary heritage, rather than some form of intelligent creation heritage, for living things. Let's start with vestigial organs.
Although creationists usually dismiss vestigial organs by saying that they have some function we don't yet understand, there are some excellent examples of vestigial organs that are not vulnerable to such criticism. These are the vestigial organs which only occur sporadically in a few individuals of a population. One example that comes to mind is that of supernumerary nipples in humans. When these occur along the mammary ridge they recall our primitive mammalian ancestors that almost certainly had nipples distributed along the mammary ridge. Since most members of our species seem to get along quite well without these extra mammary glands, we can safely conclude that they are vestigial organs that serve no useful function.
One well-known creationist friend of mine, after hearing the supernumerary nipple argument for evolutionary design, had this to say: "Extra nipples in the armpit region should convince evolutionists that we are descended from bats since their mammary glands are similarly located. And extra mammary glands located in the abdominal area would require evolutionists to believe that we have risen from whales." I doubt if I could get permission to assign this quote to a specific creationist since it should be obvious to all that the reasonable evolutionary conclusion is that bats, whales, and people are all descendants of a common ancestor that did in fact have rows of nipples along its ventral (front) surface. The creationist's response was nothing more than the old "straw man" debating technique.
The situation is identical for sperm whales. (See "True Vestigial Structures in Whales and Dolphins," Conrad, 1982.) Most members of the species get along very well without hind limbs, yet a few have stubby hind limbs complete with the appropriate hind limb bones. I am waiting for some creationist to tell me that such limbs are examples of degeneration in accord with the second law of thermodynamics. I'd love to ask from what sort of animal the sperm whale degenerated. Why did the original "created kind" have hind limbs? To climb onto the Ark perhaps? To their collective credit, however, no creationists have yet suggested anything like this.
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Certainly no elementary discussion of design would be complete without the mention of pathogens and parasites. Such organisms are completely understandable in evolutionary terms, but if they are the products of God's creation, it takes some contorted logic to save His beneficence. Invariably this involves blaming the victim. Misery exists because humans have sinned. Not only does evolution make more sense, but it relieves any supernatural forces, whatever they might be, from blame. And experience in the medical sciences has shown us that a non-supernatural approach to the study of disease has been quite productive in the alleviation of human suffering. In my opinion, every school child should be treated to what Darwin had to say on the subject. In a letter to Asa Gray he said the following:
It would be easy to go on with a veritable encyclopedia of design by evolution observations. Practically everything in biology can easily be interpreted in this way. All we need to do is ask how things would look if an omnipotent and beneficent deity had designed them and how they would look if they were the products of evolution.
For one person, the odd structure of the mammalian kidney was enough to convince her of the validity of the evolutionary viewpoint. (The kidney gets rid of an enormous volume of water in the manner of the fishes, but then must turn right around and reabsorb most of it since mammals aren't fresh water fishes.) For another person it might be the realization that vertebrates are cursed with an inside-out retina in the eye. (The nerves and blood vessels that serve the light sensitive cells pass in front of them partially obscuring the field of view. Octopuses and other cephalopods have the retinas of their eyes put together correctly with the nerves and blood vessels tucked behind the photosensitive cells.) Did God at the time of the "Fall" turn the vertebrate retina inside-out, or is the vertebrate eye a separate evolutionary accomplishment from the cephalopod eye?
There is a particularly humorous example from the history of science that calls into serious question the divine design hypothesis of creationists while, at the same time, serving to underscore the evolutionary success and taxonomic diversity of the order Coleoptera. Perhaps the story has been embellished through the years. I haven't traced the quote to the original, but it is reported that Biologist J. B. S. Haldane was asked by a reporter, "What characteristic of the deity do you chiefly discern in the design of creation?" Haldane's now famous response is reported to have been, "An inordinate fondness for beetles."
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Whether true or not, the quote captures the essence of modern divine design considerations. If we take the time to consider biology in any depth at all, we are left with a picture of a bumbling and frivolous god, one who tinkers and constantly tries minor adjustments, and who frequently doesn't get things right. The god that emerges from this type of analysis is far more concerned with the continued ability to make copies of genetic information than with the welfare of any particular species such as Homo sapiens.
On the other hand, if design considerations really show design by mutation, natural selection, and chance, one really isn't saying anything about the attributes of a deity, whether positively or negatively. From the standpoint of religion, it would seem far better to argue that life got here through the natural process of evolution than to argue that the Judaeo-Christian god is a bumbling and cruel oaf. From the standpoint of science, however, nothing can be said about the supernatural. That's why we call it natural science.
It was through references to the notion of design that Darwin convinced most of his contemporaries of the validity of evolution. Nature makes an overwhelming case for design by natural mechanisms as opposed to design by external intelligence. Gould provides many simple intuitive examples of this in The Panda's Thumb (1980).
In the face of this, it is ironic that many creationists claim that design arguments are their most successful tool for keeping the faithful faithful. Perhaps they have found such success only because few people since Darwin's time have presented to the public the much more persuasive case for design by natural mechanisms. Hopefully this exchange with Dr. Geisler will show many on the evolution side how to improve their presentation of the case for evolution.
Conrad, E. C., 1982. "True Vestigial Structures in Whales and Dolphins." Creation/Evolution 10:8-13.
Darwin to Asa Gray, Down, February 8, 1867, Life and Letters, II, 105.
Doolittle, R. 1983. "Probability and the Origin of Life," in Scientists Confront Creationists, L. Godfrey, ed. W. W. Norton.
Eigen, M., W. Gardiner, P. Schuster, and R. Winkler-Oswatitsch, 1981. "The Origin of Genetic Information." Scientific American 244:88-118.
Gould, S. J., 1980. The Panda's Thumb. W. W. Norton.
Hall, B. B., 1982. "Evolution of a Regulated Operon in the Laboratory." Genetics 101: 335-344.
Hoyle, F., and C. Wickramasinghe, 1982. Evolution From Space. Simon and Schuster.
Lewin, R., 1982. "RNA Can Be a Catalyst." Science 218:872-874. (News report).
Yockey, H. P., 1977. "Calculation of Probability of Spontaneous Biogenesis by
Information-theory." Journal of Theoretical Biology 67:377-398.
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