Start your review of Not by Chance! Nonetheless, due to his nonconformist analyses, the result is an intriguing, informative text for anyone not already ideologically committed to the two chief rival dogmatic alternatives. His book addresses the neo-Darwinian Spetner, PhD in physics and years of specialized study in organic evolution, takes the reader step by step, sometimes mini-step by mini-step, with the frequent reiteration necessary for the novice, convenient for the layman, but unnecessarily repetitious for the expert. Can the variation be random? At this point, someone not keen on math will appreciate that previously mentioned use of reminders and reiterations.
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Edward E. All Rights Reserved. The order of topics in his posting does not correspond exactly to the order of my posting, but both postings are fairly accurate representations of our dialogue. The following is my latest response 23 May in a form that reproduces his posting into which I have inserted my comments. I have identified each of our statements as he has reproduced them by putting our names in boldface followed by a colon. My new comments are inserted into the text in small caps inside square brackets and identified by "LMS".
Introduction Spetner: I am writing this essay in response to a request from Edward E. His essay is an attempt to defend evolutionary theory against attacks by creationists. Although Max scored some points against some alleged creationist arguments, he failed to defend Darwinian evolution against my attack on it in my book Not By Chance. He did not mention my book in his posting, but he referred to my book in his request for my comments.
I shall also take this opportunity to clarify some issues in my book about which some readers have written me. The principle message of evolution is that all life descended with modification from a putative single primitive source.
I call this the grand sweep of evolution. The mechanism offered for the process of modification is basically the Darwinian one of a long series of steps of random variation, each followed by natural selection. The variation is generally understood today to be random mutations in the DNA.
That primitive source of life is assumed to be sufficiently simple that it could have arisen from nonliving material by chance. There is no theory today that can account for such an event, but I shall not address that issue here. That is for another place and another time. What is relevant to this discussion is that the requirement that life arose spontaneously sets, at the very least, a stringent upper limit on the complexity and information content of the putative first organism that could reproduce itself, and thus serve as a vehicle from which to launch Darwinian evolution.
The issue I address here is the alleged development of all life by the Neo-Darwinian process of random mutation and natural selection, starting from a sufficiently simple beginning. Despite the insistence of evolutionists that evolution is a fact, it is really no more than an improbable story.
No one has ever shown that macroevolution can work. Most evolutionists assume that macroevolution is just a long sequence of microevolutionary events, but no one has ever shown it to be so. Those few evolutionists who hold that macroevolution is really different from microevolution have changed their story several times since they first came out with it, and their mechanism is so fuzzy that I cannot tell what it is.
John Maynard Smith seems to be of a similar opinion. The process must be able to lead not only from one species to another, but to the entire advance of life from a simple beginning to the full complexity of life today.
There must be a long series of possible mutations, each of which conferring a selective advantage on the organism so that natural selection can make it take over the population.
Moreover, there must be not just one, but a great many such series. The chain must be continuous in that at each stage a change of a single base pair somewhere in the genome can lead to a more adaptive organism in some environmental context.
No one has ever shown this to be possible. Now one might say that if evolution were hung up on a local Maximum, a large genetic change like a recombination or a transposition could bring it to another higher peak. Large adaptive changes are, however, highly improbable. They are orders of magnitude less probable than getting an adaptive change with a single nucleotide substitution, which is itself improbable. No one has shown this to be possible either. Moreover, as I have noted in my book, the large mutations such as recombinations and transpositions are mediated by special enzymes and are executed with precision - not the sort of doings one would expect of events that were supposed to be the products of chance.
Genetic rearrangements may not be really random at all. They do not seem to qualify as the random mutations Neo-Darwinists can invoke whenever needed to escape from a local adaptive Maximum. Evolutionists can argue, and rightly so, that we have no way of observing long series of mutations, since our observation time is limited to a relatively short interval.
Our genetic observations over the past years are more like a snapshot of evolution rather than a representative interval in which we can search for the required long series of changes. But our inability to observe such series cannot be used as a justification for the assumption that the series Darwinian theory requires indeed exist.
Max: I agree that there are no definitive examples where a macroevolutionary change such as the development of cetaceans from terrestrial mammals has been shown to result from a specific chain of mutations. Those two statements are not symmetrical. You, who are basing your theory of evolution on the occurrence of such a series, are required to show that it exists, or at least that it is likely to exist.
You are obliged to show an existence. I am not obliged to prove a non-existence. Then we must extrapolate as best we can the information learned from these model systems to the questions of species origins. This extrapolation from laboratory model systems to systems unobservable in the laboratory is the method of science common to medicine, astronomy, chemistry, meteorology, physics, etc.
Because we can access only genomes of modern or very recent species, we can never obtain the direct evidence—i. Behe seem to think would be necessary to support NDT. Evolutionists have the job of defending the reasonableness of such a series of mutations. I believe that Spetner would agree with this. The theory requires there be a vast number of possible point mutations which, coupled with natural selection, can produce the evolutionary advances that could produce the grand sweep of evolution.
Because there must be a large number of qualifying mutations, at least a few of them should have been observed in some of the many genetics laboratories around the world. All the mutations in these long series must not only confer selective advantage on the organism but they must, on the average, also contribute to the information, or complexity, increase that surely distinguishes present-day life from the putative primitive organism. These mutations must have whatever characteristics are necessary for them to serve as elements of the grand sweep of evolution.
Thus, for a mutation to qualify as a representative member of the required multitude of long series that are supposed to produce evolution, it must bring new information not just to the genome of the organism, but the information must be new to the entire biocosm.
The horizontal transfer of a gene from one species to another is not information new to the biocosm. To show evolution in action, one must at least demonstrate examples of a mutation that can serve as a prototype of those required by the theory. Such a mutation must be one that could be a contributing member of a series of mutations that could lead to the vast increase in information required by the theory. Thus, for example, a mutation that disables a repressor gene causing a constitutive synthesis of an enzyme might be advantageous to an organism under special circumstances, but the disabling of a gene does not represent the mutations required by the theory.
Although some opponents of evolutionary theory may have advanced the arguments he attacks, those arguments are in large measure straw men that Max busies himself with refuting.
The B-Cell Hypermutation Model Max: The next major point of discussion in the correspondence has been about how well the model of immunoglobulin gene somatic hypermutation in B cells serves as an analog to genomic mutation in evolution. He implied that Evolution could follow this method to achieve baboons from bacteria.
I agree with him that these mutations add information to the B-cell genome. I also agree that they are random, but they are random only in the base changes they make; they are not random in where in the genome they can occur. More important, I do not agree that the grand sweep of evolution could be achieved through such mutations. Although the somatic mutations to which Max referred are point mutations that do indeed add information to the genome of the B cells, they cannot be applied to Darwinian evolution.
These are not the kind of mutations that can operate as the random mutations required by NDT that can, through chance errors, build information one base change at a time. For one thing, the rate of the somatic mutations in the immune system is extremely high - more than a million times normal mutation rates.
For this reason they are called hypermutations. If an organism had a mutation rate that was even a small fraction of this rate it could not survive. For a second thing, the hypermutations in the B cells are restricted to a specific tiny portion of the genome, where they can do no harm but only good. The entire genome of the B cell could not mutate at this rate; the hypermutation must be restricted only to the portion that encodes selected portions of the variable part of the antibody.
These rates are incompatible with Darwinian evolution. No, Darwinian evolution could not occur with such rates. These high rates are essential for the working of the immune system. A lower mutation rate would make for a less efficient immune system.
The high mutation rates, so necessary for the immune system, if applied to an entire organism for evolutionary purposes, would be fatal many times over. Note that these hypermutations are limited to a restricted portion of the genome. Moreover, the hypermutations are mediated by special enzymes. Thus, although the hypermutations are random in the changes they make in the bases of the genome, they are not random in the positions in which they occur.
They occur only in the small region in which they are needed, and occur there through enzymes that apparently play only that role. Furthermore, they occur only when they are switched on by the controlling mechanism of B-cell maturation. Thus it is clear that the hypermutations in B cells cannot serve as a prototype for the random mutations required for NDT.
If adaptive mutations that increase information in the genome of a B lymphocyte population can occur over one week given a high mutation rate, what theoretical argument would lead you to reject the idea that adaptive mutations that increase information in the genome of a germ cell population could occur over many millions of years given a much lower mutation rate?
Evolution requires a long series of steps each consisting of an adaptive mutation followed by natural selection. In this series, each mutation must have a higher selective value than the previous. Thus, the evolving population moves across the adaptive landscape always rising toward higher adaptivity. It is generally accepted that the adaptive landscape is not just one big smooth hill with a single Maximum, but it is many hills of many different heights.
Most likely, the population is on a hill that is not the highest in the landscape. It will then get stuck on a local Maximum of adaptivity and will not be able to move from it. This is particularly likely because the steps it takes are very small - only one nucleotide change at a time.
The problem is compounded by the lack of freedom of a single nucleotide substitution to cause a change in the encoded amino acid. A single nucleotide substitution does not have the potential to change an amino acid to any one of the other In general, its potential for change is limited to only 5 or 6 others. Moreover, the probability is close to 1 that a single mutation in a population, even though it is adaptive, will disappear without taking over the population see my book, Chapter 3.
Therefore, many adaptive mutations must occur at each step. The hypermutation in the B cells does this. It achieves all possible single, double, and triple mutations for the immune system, which allows them to obtain the information necessary to match a new antigen.
Lee Spetner/Edward Max Dialogue
Education[ edit ] Spetner received his BS degree in mechanical engineering at Washington University in  and his Ph. In , he became technical director of Eljim, Ltd. Spetner published several papers on the subject of evolution between and Spetner was inspired by Rabbi David Luria - , who calculated that, according to Talmudic sources, there was originally created species of beasts and of birds.
Not by Chance!: Shattering the Modern Theory of Evolution