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a review of Lee Spetner's "NOT BY CHANCE!"
by Gert Korthof
Dec 31 1998 (updated Oct 18 2003)
IntroductionCharles Darwin wrote in the Origin of species that species are not fixed as Linneaeus taught, but that all species descend from one or a few ancestral life forms; and the mechanism underlying the transformation of species was heritable variation and natural selection. This is still accepted by the majority of biologists today. Regarding the nature of mutations, scientists universally accept that mutations are copying errors of the bases in DNA and further (with a few exceptions) that these mutations are random. 'Random' means that those mutations are unrelated to the effects they may have for the organism. It is also generally accepted that most mutations are harmful and will disappear, and that a small percentage is beneficial. This fraction of positive mutations will be selected and will be represented in the next generations. Just enough to drive evolution. However there is a small minority of scientists who claim that there are simply not enough positive mutations to drive evolution. Dr. Lee Spetner is one of them.
Neo-Darwinism: Could it work ?
|2.1||Richard Dawkins' weasel experiment as a test case
Let's start with Spetner's criticism of one of the well-known examples of Richard Dawkins. Dawkins described a computer experiment to demonstrate the difference between one-step and cumulative selection (1). He started with a random string of 28 letters. He programmed the computer to change at random one letter at a time and let the computer operator select a letter until the string reads:
METHINKS IT IS LIKE A WEASELThe random substitution of a letter simulates random mutation of DNA and the selection of a letter that matches the target string simulates natural selection. Spetner's acknowledges the point of Dawkins weasel example:
there is a much larger chance for cumulative selection to occur than for one large adaptive step. (p.162)Despite the fact that Spetner knows what the purpose of Dawkins example is and that Dawkins admits that his weasel experiment is not realistic, Spetner spells out the reasons why it is not realistic:
"Dawkins choice of a large mutation rate is one reason that his simulation works"In nature the mutation rate is a billion times lower: 1/10,000,000,000. Indeed, it needs to be low otherwise organisms will not survive. But it cannot be too low, otherwise adaptation to changing environments is not possible. Further, mutation must not be too low, because evolution has only 3 billion years to create humans from nothing. Spetner argues that if a realistic simulation were run with a mutation rate of 1/10,000,000,000 (10-10) and a sequence length of 500, then the simulation would take 70 billion steps just to get the mutations.
Spetner's criticisms have such a strong eye-opening effect, because the weasel experiment is so attractive. It is so successful that one forgets that it was not intended as a proof of evolution. Perhaps the weasel experiment could have been made more realistic by introducing a series of viable intermediates that serve as short term goals for selection. But that would not make it more easy to understand. It is obvious now that Dawkins used a simplified example to illustrate cumulative artificial selection. However Spetner's model is too simple too, because
Could accumulation of many random mutations create new species?
Spetner's central question (in chapter 4) is: How many small random mutations are needed 'to get a new species' ? In the scientific literature 'to get a new species' is known as speciation. Spetner doesn't use the word; it is not in the index. Speciation is defined as splitting up of one species into two. In the literature one can easily find: (1) what happens to mutations in populations under the influence of selection and chance, (2) a lot about speciation mechanisms, (3) how many generatons are needed to produce reproductive isolation, but not: (4) how many mutations are needed for speciation. Yet it seems to be a legitimate scientific question. For if neo-Darwinism claims that mutations arise with a certain (low) frequency, and if they are entirely random (that is: unrelated to the needs of organism), and if only a fraction of them is positively selected, and if 500 point mutations are needed to create a new species, and if the resulting probability is too low, then that particular collection of assumptions plus model is falsified. Logically the theory could still be right and any of the assumptions could be wrong. Spetner devotes chapter 4 to this calculation and gives all the assumptions, steps and details supplemented with notes. He takes care to get the figures from the scientific literature, although not always recent literature. For example Stebbins(1966) estimated that 'to get to a new species' would take about 500 steps (=point mutations) (3). So far the textbooks. But then Spetner takes over. He calculates the total probability that all 500 steps occur successfully in a row. The extreme small probability 2.7x10-2739 Spetner arrives at, results from multiplying the probability of each step 1/300,000 by itself 500 times (p. 103). Spetner concludes that it is impossible that a new species could ever originate in this way. There are just not enough favourable mutations in the time available to produce new species. I think that Spetner's model is wrong because his underlying speciation model is wrong.
Non Random variation
|3.1||Spetner's Non Random Evolutionary Hypothesis (NREH).
Well, if Spetner thinks random mutations could never cause macro-evolution, what is his alternative? Please note that nobody is obliged to come up with an alternative in order to criticise Darwinism, but Spetner happens to have an alternative theory. His alternative is: the Non Random Evolutionary Hypothesis (NREH). He claims that NREH produces some large-scale evolution (macro-evolution), but gives no the details. He is silent about common descent (9). Remarkably Spetner does not straightforward deny macro-evolution, he claims that neo-Darwinism (accumulation of small changes) cannot account for macro-evolution. This would imply macro-evolution exists. What is clear that he denies that macro-evolution is an extension of micro-evolution. Further he claims that NREH is a better explanation for micro-evolution. Spetner accepts that micro-evolution occurred. He disagrees about its causes.
When evolutionists say genetic variation is random, they mean variation is unrelated to the fitness of the organism. Here is Spetner's alternative:
When I say a variation is not random, I mean that the chance of it occurring has something to do with how the organism adapts to its environment (p. 175).Spetner claims his hypothesis explains many observed phenomena that neo-Darwinism does not explain. One advantage of the NREH would be that the evolutionary process need not be prohibitively slow. In fact an adaptation would occur instantaneously on an evolutionary time scale! There would be no cumbersome selection process over many generations. It this is true, why doesn't the fossil record show human fossils a few hundred million years earlier?
What is the evidence for Non Random Variation ?
Spetner mentions mutation in the flagellin proteins of Salmonella and transposable genetic elements, but most detailed are the reports of Barry Hall (p187). Dormant ("cryptic") genes becoming active in E. coli in response to the presence of lactose in the environment (Barry Hall,1982). The remarkable fact is that two mutations occurred in the same bacterium, both needed for survival, and that the probability of that event is 10-18! Which is extremely small. If the mutations did occur at random, he would have to wait a hundred thousand years. But in the presence of lactose he found 40 of them in just a few days. Neither of the two mutations is of any use by itself. Spetner interprets this as non-random adaptive mutations. Hall continued his research in 'adaptive mutation' and published in 1997,1998 and 1999 about it (10). The facts are not controversial, but their interpretation is.
Non Random mutations: Could it work?
Does Spetner apply the "Could-it-work?"-formula to his own Non Random Evolutionary Hypothesis? No! So, is Spetner using a double standard? He forgot to ask these 3 questions:
The third unanswered question is: assume that 'adaptive mutations' exist, are they adding information to the genome ? Spetner does not tell us. But he devotes a whole chapter on this issue when talking about random mutations! Activation of dormant ("cryptic") genes by definition adds no information to the genome, because those genes already exist in the genome.
Spetner claims that only 'adaptive mutations' can explain macro-evolution, but they fail to pass his own tests for macro-evolution! Spetner is honest enough to state that the experiments with bacteria are controversial and that the problem has not yet been resolved. Spetner is also realistic enough to understand that science needs to be conservative " to prevent science from fitfully chasing after every harebrained experiment" (p. 190). So far Spetner's 'adaptive mutations' are miracles. Not the right kind of stuff to build an alternative theory on.
Can random variation build information?Can random mutations really build something good and something new? Could random mutations build the photoreceptors, the muscles for focusing, etc of the eye? asks Spetner. Spetner investigates the answers he found in the literature. He uses an increase in information as a criterion for the adequacy of the mutations for macro-evolution: do those mutations add information to the genome? If not, they are not the right type. Everybody agrees that humans have more information in their genomes than bacteria. So we must see this increase in information in individual mutations argues Spetner. Although Spetner later (9) recognises that the mathematical concept of information is not very helpful in clarifying biological problems, the increase in genetic information is real. He is not satisfied with often-mentioned examples such as resistance to streptomycin and DDT, because "all point mutations that have been studied on the molecular level turn out to reduce the amount of information" (p138).
I think the problem with the examples he examined (and those presented by Darwinists) is that they are all short-term 'solutions' to environmental problems of bacteria and insects. Of course these cannot show the real long-term innovations of vertebrates (the eye, brain, placenta) or the construction of 35 unique body plans in the Cambrian Explosion. Mutations detected in experimental conditions start with phenotypes (resistance to antibiotics), and go back to the enzymes involved, and further back to the gene. However that is the wrong approach and the wrong place to look. Everything we find out about mutations in living organisms in nature or in the laboratory tends to be irrelevant for the problems of macro-evolution, because neither we, nor natural selection, know in advance what future use can be made of a mutation. One has to look at complete genomes, identify genes (for example) for the eye and subsequently find organisms with similar genes that are not yet used for building an eye. Those genes are the precursors. Only then can we trace the path that genes followed in building new organs. Unless one believes in a miracle every time an eye develops in an embryo, an eye is built by genes just like any other organ. Those genes are similar to other genes. For example the fact that we can see red and green colours is caused by two opsin genes. The two genes are identical for 96% and this points to a recent gene duplication. Another example: lactation is an 'innovation' of mammals. How did it originate? Lactalbumin, one of the main proteins in mammalian milk, has been considered to have arisen de novo in the ancestor of mammals. Molecular studies, however, have shown that lactalbumin is not a mammalian innovation, but rather a modification of lysozyme, a ubiquitous enzyme found in a wide range of organisms from bacteria to plants, and a very ancient protein (12). How would Spetner recognise this, if he only looks at mutations in bacteria? Only with hindsight one could say that certain mutations in lysozyme would 'add information' because they are halfway towards lactalbumin. Spetner and many Darwinists did not realise they were looking at inadequate evidence to verify or falsify the neo-Darwinistic theory of macro-evolution.
What kind of creationist?Spetner is a theist. The Judaica Press is religious. Spetner published an online article about the relation between Darwinism and the Torah (13). It is clear that Spetner has a motive, but that does not make him 'guilty'. Calculations cannot be Jewish. Clearly Richard Dawkins, being an atheist, has a motive. But calculations cannot be atheist either. There is no religion in Not By Chance, except in his Epilogue where Spetner discusses the Torah concept of creation. He even claims that his Non Random Evolutionary Hypothesis is derivable from Talmudic sources. That explains his motives behind the NREH. Furthermore his motives also influenced the contents and the nature of his own hypothesis:
ConclusionLee Spetner, a physicist, presented a scientific (mathematical) critique of neo-Darwinism and scientific, but controversial alternatives. He has religious motives, and religious escape routes. He asked non-orthodox but stimulating questions (18) and presented some unorthodox answers. Spetner published in mainstream peer-reviewed scientific journals: Journal of Theoretical Biology in 1964, and Nature in 1970. In that sense he is an insider and contributed to science. At the same time he makes himself an outsider, by ignoring knowledge about speciation. He accepts controversial results about nonrandom mutation and builds his own theory: the 'Non Random Evolutionary Hypothesis' on those controversial results. Spetner explains these results by a mysterious 'set up' of the genome.
Spetner is not a Young Earth Creationist. He probably accepts the Big Bang, but avoids questions such as the age of the earth and the chronological order of fossils in the fossil record, so he doesn't need to explain that the fossils are in the right order. He avoids mentioning the universality of the genetic code, so he doesn't need to explain why all life on earth has the same genetic language. He avoids discussing the hierarchic structure of life, so he misses crucial evidence for the common descent of all life. Furthermore he misses the central task of biology: explaining the existence of a million species. He constructed his 500-step speciation model as a disproof of neo-Darwinism and macro-evolution, but the situation is more complex than that. Evidence for the common descent of life (fact) does not depend upon the truth of neo-Darwinism (mechanism), because there is a difference between the fact and the mechanism of evolution.
His criticism of Dawkins weasel experiment shows that a defence of evolution is incomplete without a full account of the conditions that make evolution work. Spetner himself pretended to give a full scientific account of population genetics in a short popular book. The value of Spetner's 'Could it work?'-approach is that it stimulates critical thinking about the problems and solutions of neo-Darwinism. Especially because he is trying to refute neo-Darwinism. An approach which is absent from introductory textbooks. Textbooks present established facts and omit nasty unsolved problems. Textbooks and to a lesser degree scientific journals tend to ignore crucial questions of how new genes are created and focus on neutral or slightly deleterious mutations and 'purifying' selection (16). The title 'Not By Chance!' is misleading, because evolution has a random component (mutation) and a non-random component (natural selection). Spetner's dream: a physicist falsifies the foundations of modern biology, or in his own words "shattering the modern theory of evolution", did not come true.
PostscriptThe claim of forgery of the London and Berlin Archaeopteryx specimens seems to have been started by Dr. Lee Spetner at a meeting of orthodox Jewish scientists in Jerusalem in July 1980. (source: Arthur Strahler (1987) Science and Earth History, p. 426.) [added Oct 2 1999]. See further: Paul Chambers (2002) Bones of Contention. The Archaeopteryx Scandals.
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|Copyright ©G.Korthof 1998||First published: Dec 31 1998||Updated: 18 Oct 2003. Notes/F.R.: 24 Nov 06|