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Do We Have an Evolutionary Theory?

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This is a preview of a paper by John A. Davison that will be appearing in Rivista di Biologia and ISCID Brainstorms.

Do We Have an Evolutionary Theory?

Dear Editors,

The word theory has several definitions. To facilitate discussion I am going to define theory as follows. A theory sensu strictu is an hypothesis which, having been tested, has achieved a degree of support, thereby enabling it to make certain predictions. When this definition is applied to evolution some curious conclusions emerge.

I will present these conclusions first with respect to the two major hypotheses which have dominated evolutionary science for over a century. These are the Lamarckian hypothesis of the inheritance of changes produced during the life of the individual and the Darwinian hypothesis that Nature selects random changes in genetic composition resulting from undirected mutations. I will then consider the possibility that evolutionary mechanisms are not amenable to experimental analysis, a suggestion presented by Schindewolf. (1993). Having done so, I will then apply the same criteria to the Prescribed Evolutionary Hypothesis which I have recently offered and which was anticipated independently by William Bateson, Leo Berg , Robert Broom and Otto Schindewolf (Davison, 2005).

Are all hypotheses testable? This fundamental question has significance because it implies something that may not be amenable to realization. That is to say that if a result cannot be anticipated, the hypothesis simply does not exist. It is interesting to compare Lamarckism and Darwinism in this respect. Lamarckism is eminently testable because it makes highly specific predictions. As such it is a fine hypothesis. The classic example of the giraffe stretching its neck is an example and one considered by Lamarck. Of course we know now from certain African tribes that engage in this practice that the effects are not transmitted to the next generation. The failure of mutilations to be transmitted has been known since antiquity. Darwin’s own Pangenesis hypothesis was tested by August Weismann in Darwin’s own day with negative results. There is still no convincing demonstration that such factors have played a major role in organic evolution. However, let me say that since macroevolution is not demonstrable today, it remains conceivable that Lamarckian devices could have been of importance, perhaps even of great significance, in the past.

It is when we come to Darwinism that things become both interesting and revealing. Central to the Darwinian hypothesis is the notion that Nature does the selecting of that which is essential for evolutionary progress. Of course Nature is not subject to experimental control and so we have had to substitute artificial means of selection to simulate that which has been assumed to have been the mechanism. While there is no question that varieties can be produced through artificial selection, to the best of my knowledge such attempts have as yet never successfully exceeded the species barrier. This experience includes centuries of efforts on the part of animal and plant breeders to alter all kinds of domesticated organisms. Furthermore, since Nature is at the very least unpredictable, we are left with the conclusion that the Darwinian model does not qualify even as an hypothesis, a curious status for a view still widely accepted by the evolutionary establishment.

There is another reason to question the validity of the Darwinian hypothesis. Since Nature was somehow created, the question arises as to exactly when in the creative process did the Creator transfer the reins of the creative process over to Nature, that which had been previously created? My answer to that question is never.

Now we come to the hypothesis that evolution resulted from the expression of endogenous forces not directly subject to experimental analysis. This idea may be traced back first to William Bateson, then to Leo Berg and Robert Broom, next to Otto Schindewolf and finally to myself in the form of the Prescribed Evolutionary Hypothesis (PEH). I have recently reviewed the history of this idea and the evidence in support of it (Davison 2005). On the face of it such an hypothesis would seem to be untestable and as such would not seem to be of scientific significance. Yet, having dispensed with major alternatives, is it even necessary to apply an experimental criterion to evaluate its validity? Is it necessary to test the validity of Mendeleef’s Periodic Table of the Elements or Galileo’s Law of Falling Bodies just to pick a couple of examples? I answer no as such phenomena demonstrate themselves. When it can be shown that the simple rearrangement of chromosomal information can produce profound heritable phenotypic effects, in other words evolution, does that in itself not constitute a proof that the information was always there and required only to be unmasked? When there is no demonstration that allelic substitutions have ever played a role in macroevolution, does that not require the abandonment of the entire Darwinian paradigm?

I further propose that while such a predetermined evolution may not be amenable to experimental analysis as Schindewolf claimed, the fact remains that it has never been subjected to experiment. In other words whether or not Schindewolf was correct has yet to be ascertained. I first proposed such a test (Davison 1984) with the paper “Semi-meiosis as an Evolutionary Mechanism.“ To my knowledge the Semi-meiotic Hypothesis (SMH) has yet to be tested employing material bearing chromosomal rearrangements in heterozygous form. That hypothesis predicts that a female heterozygous for a chromosomal rearrangement will, following the first meiotic division of her oocytes, have gynogenetically produced normal diploid offspring half of which will be homozygous for the original karyotype and half homozygous for the new rearrangement. Until those experiments have been carried out, the PEH must be considered viable. Moreover, since the Darwinian establishment no longer tests its own hypothesis, it is understandable why it might not wish to test the SMH. Nevertheless, it cannot be dismissed without laboratory inquiry into its validity. The PEH and the SMH are two faces of the same coin and experimental support for either will be support for both.

So it would seem that we still do not have a working theory of evolution. What has been firmly established however is the total failure of the gradualist Darwinian model to survive the test of experimental selection and the undeniable realities of the fossil record. Until that paradigm is formally discarded, I see little hope for progress in evolutionary science.

John A. Davison

Professor Emeritus of Biology, University of Vermont
Mailing address: L4 Grandview Drive, South Burlington, VT 05403
E-mail: nosivadaj@msn.com

REFERENCES

Davison, J.A. [1984], Semi-meiosis as an Evolutionary Mechanism. J Theor. Biol. 111: 725-735.

Davison, J.A. [2005], A Prescribed Evolutionary Hypothesis. Rivista di Biologia / Biology Forum 98: 155-166.

Schindewolf, O. [1993]. Basic Questions in Paleontology. University of Chicago Press, Chicago (original German edition, 1950).

Comments
I'll tell you anyway. Rocky Mountain oysters occur in pairs. When removed they convert raging bulls to docile steers, sort of like what has happened to Darwinians these days. John Davison
I presume everyone knows what Rocky Mountain Oysters are. If you don't just ask? I'll be happy to explain. John Davison
In future I will refer to them as testacles or maybe male sex organs which seem to be missing in most Darwinians. John Davison
You will find the paragraph in my "An Evolutionary Manifesto: A New Hypthesis For Organic Evolution" which is available at what used to be my home page before the university froze it: www.uvm.edu/~jdavison or at ISCID's "brainstorms" forum in the Archives. It was also discussed there at great length quite some time ago. I recommend you read that paragraph in the context in which I presenteed it which makes it all the more devastating to the Darwinian fantasy. Better yet, go to the library and read the original source. You can get a copy cheap from Barnes and Noble too. Thanks for asking. John Davison
Professor Davison: "Julian Huxley. Remember him? He is the one that coined the term 'Modern Synthesis' and then shot it all to hell in a single paragraph on page 571 of his book 'Evolution: The Modern Synthesis.' " Could you please transcribe and post the paragraph, in the interest of the edification of everyone here? Thanks. j
I sure hope the creeps at Panda's Thumb are reading this stuff. I hope someone will alert them. I can't because the cowards banned me long ago. Some one please remind them that their precious hypothesis is going down in flames. I'll look in on "After The Bar Closes" for verification that they are getting the message. That is until the swine ban me from even viewing their stinking pig sty, Wesley Elsberry's inner sanctum. "War God help me, I love it so!" So do I George. We were "prescribed" to be that way. No doubt about it. How do you Darwinian eunuchs like them Rocky Mountaun Oysters on the half shell? John Davison
The best indirect evidence favoring the SMH is that fact that nearly all eggs, includimg those of humans are still diploid at the moment the sperm enters thus making a semi-meiotic origin perfectly feasable in the past and certainly demonstrable experimentally. The only animals I know of that have haploid eggs at the moment of sperm penetration are some of the Echinoderms and they stopped evolving millions of years ago at least according to Robert Broom and that curious schizophrenic Darwinian, antiDarwinian, Julian Huxley. Remember him? He is the one that coined the term "Modern Synthesis" and then shot it all to hell in a single paragraph on page 571 of his book "Evolution: The Modern Synthesis." Yes that's him! I ask once more - why don't the Darwinians test the Semi-meiotic Hypothesis and prove once and for all that I am wrong. We all know the answer. It is for exactly the same reason they quit testing their own idiotic hypothesis. You don't really expect these chance worshipping mystics to take any more chances do you? I sure don't. No guts no glory and no opportunity to go down in flames either. War, God help me I love it so! So do I George baby! Let's get it on. I'm not getting any younger. John Davison
I always have Dave. Asking "who is next" is what got me banned at EvC. I love it so! And we thank you for your support. John Davison
The validity of your points, Professor Davison, are only exceeded by the colorful way you have of expressing them. Thanks for your answers. You may now ask who is next. ;-) DaveScot
I think he might be talking about The Church of Darwin. Yes, that's probably it. DaveScot
Well? John Davison
Which one is that? John Davison
Why not look for a religion which offers empirical confirmation of its theological claims? One does exist. jaredl
Here are the instructions on how to proceed with mice or rats, both of which are induced ovulators. Stimulate ovulation with a pseudo-copulation. Then open the animal up and activate her ova with irradiated sperm as they appear. Then immediately inhibit the second meiotic divison with colchicine or some other microtubule inhibitor. wash away the inhibitor, following which the activated eggs can be placed in a foster mother to complete their semi-meiotic development, a development which I am confident will be perfectly normal. I would expect that either sex might be produced this way although females are the more likely. It would be a little stickier with humans but I understand some women can tell when they are ovulating. After demonstrations with rodents, find yourself a nice willing gal and give her the opportunity to make evolutionary history. You might have to pay her of course. We all know about that! Now pay attention FUNDAMENTALISTS EVERYWHERE WHEREVER YOU MAY BE to what I am about to say. This expermental procedure could offer a rational, scientifically based explanation for both the Immaculate Conception of Mary as well as a potential demonstration of the Virgin Birth of Christ. It has already been done with frogs. Don't forget who told you so. That does not mean that I necessarily subscribe to either dogma although I may have a death bed conversion. I haven't decided yet. Now lets get cracking with some real experiments and stop all this empty rhetoric. How do you like them fermented olives with those cute little plastic toothpicks in them? John Davison
Incidentally, I know of no frogs that normally produce semi-meiotic offspring. That can only be demonstrated experimentally. That is what science is all about. You can stare at the living world until your nose bleeds and you will learn nothing about evolution. Darwin proved that beyond a doubt and so has Richard Dawkins and every Darwinian in between. I hope you are listening over there at "Panda's Pathetic Pollex," also know as "Elsberry's last stand" and the "Alamo of Darwinian mysticism." I love it so! Invite them in Dave, one at a time, where we can really let them have it with both barrels. Of course they won't show anyway. I already proved that at my blog. Cowards are like that don't you know. As Harry Truman once said of Harold Ickes I think it was: "He is a living miracle with neither brains nor guts." He also said: " Never kick a fresh turd on a hot day." John Davison
I have no idea. All I know is that every living thing on this planet that produces haploid gamtes does it the same way. They do it in two steps, the first of which is a perfectly normal form of diploid reproduction which intrinsically can produce new paired chromosome homozygotes in a single cytogenetic event which is, as far as I am concerned, the critical step in creative evolution. If the only purpose for meiosis was to make haploid gametes it would never have evolved the way that it did. There would be a single synapsis, crossing over, and a single separation. I know of not a single sexually reproducing form that does it that way. We see in meiosis an evolutionary sequence which I believe discloses the mechanism of organic evolution, something that is apparently no longer going on. I am also convinced it will never be resumed for the same reason that dead animals and plants to not return from the dead. "You are lost and gone forever, oh my darling Clementine." I am confident that experimental semi-meiosis could be carried out in any number of creatures including man. Just don't expect it to be attempted by an atheist, chance happy, natural selection intoxicated Darwinian. They don't even have the balls fiber to test Darwin's finches. What a bunch of homozygous losers they really are. I love it so. I hope they are listening in over at "After the bar closes." How do you like them overcooked Polish sausages drenched in Deli mustard? Spicy aren't they. I hope they give the Darwinians ulcers. Overstrike added by management. We try to avoid cussing. John Davison
I think you elaborated on what was in the manifesto which is what I was looking for. Question - I believe frogs are unusual in their ability to produce gynogenetic offspring. Is it your proposition that all organisms using obligatory sexual reproduction speciate in this manner and how would we verify it works in anything other than frogs? DaveScot
Dave It is implicit in the methods that have been used to produce triploid frogs. They are produced by heating the egg shortly after fertilization which prevents the second meiotic division from taking place. George Nace produced gynogenetic (semi-meiotic)diploid frogs by using irradiated sperm and then preventing the second meiotic division from taking place. They contribute no chromosomes but serve only as a stimulus. Also Loeb way back early in the century was sticking needles into frog eggs to turn them on and produced 20 or so normal diploid frogs. The vast majority (thousands) of such eggs fail to develop into frogs becasue they are haploids and haploids don't make it past early stages. The gynogenetic, semi-meiotic diploid normal frogs could only be the result of spontaneous failures of the second meiotic division. They were as I recall 15 male, 3 female and 2 of uncertain sex. Parmenter proved they were diploids with 26 chromosmes. I found an occasional triploid frog in ordinary normal fertlization. The whole thing is laid out in my Manifesto in detail with citations to the literature. The remarkable thing is that triploid frogs can be perfectly normal, always becoming males and of course invariably sterile because with three sets of chromosomes it is quite impossible to carry out a normal meiosis. These and other experiments which I cited show that all the necessary information to produce both sexes is contained in the female genome. Incidentally, any major change in the structure of any single chromosome is going to result in unbalanced gametes being produced during meiosis because if a cross over occurs at any point in the paired region prior to Meiosis I, unbalanced gametes result and the resuslting zygote will die. Accordingly it is not necessary to postulate any point genetic mutations to account for speciation. It could all be due only to alterations in chromosme configuration. The beauty of the semi-meiotic hypothesis is that it automatically is going to produce normal chromosome homozygotes one half of which will be normal original karyotypes, the other half a new homozygous chromosome configuration, in principle a new species. The formation of the chromosome homozygote was always a problem for Goldschmidt and the first meiotic division provides the answer. I am surprised he didn't recognize it. There is nothing gradual abut a cytologically instantaneous event. Mutations play no role in this mechanism. I don't think allelic mutations ever had anything to do with evolution and neither did Goldschmidt, Broom, Berg or Grasse. That is why the Darwinians ignore them. They have hitched their wagon to a boulder and like lemmings they march on toward the sea and certain destruction. I love it so! One of the problems was that Grasse never accepted Goldschmidt's views on the chromosome being the unit of evolution. Grasse also ignored Berg and Bateson too. I think the trouble is that the French have had the crap beaten out of them by the English, the Germans and the Russians all. They still think today that they are the only nation in the world that is worth anything. There has always been a strong element of nationalism in evolutionary theory. Most of the real "crazies" have been Americans and Britishers with the notable exception of William Bateson and his friend and colleague Reginald C. Punnett, both excellent geneticists and naturalists. Bateson was a great genius and skeptic, an indispensable feature for a real scientist. The craziest of them all is unquestionably "Sir" Richard Dawkins. He mentions absolutely none of the real pioneers in evolutionary science, even fewer than the ones that Gould, Provine and Mayr managed to ignore. He is a force unto himself. I don't see how he will be able to deal with what is happening to his maniacal convictions as the experimental laboratories continue to erode and expose the Darwinian fairy tale. It will be fun to watch. I just hope I last long enough to enjoy it thoroughly. I have already developed a callous on my right thigh. There is absolutely nothing in the Darwinian model that is worth a nickel. It is all fantasy. I hope this helps. John Davison
Have you written a paper I can reference that describes the test procedures for your hypothesis? DaveScot
Dogen 3 The recognition that the chromosome, not the gene is (more accurately was) the instrument of evolution is not unique with me at all. It was recognized 65 years ago by Richard B. Goldschmidt and again more recently be Pierre Grasse. Allelic mutation is not creative and never was. The Darwinian establishment has simply not allowed those revelations to be recognized. This they have done by ignoring both of these great biologists. That is why they continue to ignore me when I champion those pioneers. That has always been one of my primary purposes. They dare not open this Pandora's Box because they know it spells their doom. Instead they go right on pretending none of us (there have been plenty of us) do not and have not existed. It is as simple as that. I recently visited Barns and Noble book store to discover that Dawkins, like Mayr and Gould before him, has also ignored the six to which I have dedicated my work. These people don't dare mention us even though we are nearly all dead or, more accurately, nearly dead. At 78 I can't expect to live to be a hundred like Mayr did. Mayr and Gould avoided the show down by dying. I don't think Dawkins is going to be so lucky, certainly not if it is up to me. He is little more than a "snake oil" salesman if you ask me. I have already called him out in the street at high noon. Of course nobody else showed either. I love it so! I'm delighted. DaveScot Thanks for clearing that up. I thought for a minute you had a brand new hypothesis for evolution to present. Of course you, like everyone else, had that opportunity at my blog and nobody showed. I attach great significance to that. It may very well prove to be true that retroviruses might help in the rapid spread of a new species once created. Leo Berg felt that whole populations were involved in the simultaneous creation of new species. I believe that like every other genetic change, evolutionary changes orginated in the genomes of individual organisms not populations. Population genetics has now and never had anything to do with creative evolution. It deals only with the distribution of genes within an interbreeding population. When the Darwinians couldn't demionstrate the evolution of individual organisms thet turned to populations in mystical desperation, led on primarily by Ernst Mayr. Even Sewell Wright never claimed more than what could be shown to be real and he respected Goldschnmidt's saltational views as well. Since macroevolution (true speciation and the formation of any higher categories) cannot even be demonstrated, I am inclined to stick with known cytogenetic devices to explain a past evolution. Those include the first meiotic division which most certainly must have evolved before the second and accordingly must be the more primitive. Once the second appeared and it did so independently, apparently many different times, all creative evolution came to a standstill as creatures began obligatory sexual reproduction. It has never been demonstrated that any living thing can transcend even the species barrier through the mode of sexual reproduction even through the most intensive artificial selection. I think it is quite impossible. The one thing sexual reproduction is really good at is ensuring ultimate extinction, the story of the fossil record and the contemporary scene. Extinction is ALL that we see. This is still the scenario to which I adhere and will adhere to until I must abandon it for good experimentally verified reasons. That I have always been willing to do and so far haven't had to. The secrets of evolution will be disclosed at the laboratory bench and nowhere else and certainly not on internet forums. John Davison
I didn't say or imply mobile elements were creative any more than you say or imply semi-meiosis is creative. I point to it as an alternative to semi-meiosis - a mechanism only. DaveScot
If I understand your earlier work you propose that "evolution" occurs at the level of the chromosome, not the gene, which is unique. But you also make a big deal about speciation being independant of natural selection. How is that really different from other evolutionary biologists? And what are the implications of this (assuming we are not going to resort to a God that influences evolution on an itermitant rather than up-front or ongoing basis)? Dogen3
It wasn't even elsewhere. Tt was right here in the paper which is the subject of this thread. Does anyone read anymore? "You can lead a man to the literature but you cannot make him comprehend it." John A. Davison John Davison
I have never denied Lamarckian inheritance in the past and I even suggested it might have been of great importance as I explained elsewhere. I see no evidence for it as a creative element at present. If you see it implicated in a current evolution, please document it for me. I have an open mind. John Davison
I am sure my local Bishop isn't even remotely interested in what I think about God and he shouldn't be. Catholics are not evangelists trying to convert the whole damn world. They even believe in a free will. I sure don't any more. That may be the only thing John Calvin got right. What I want to know is when is there going to be a "Protestant Academy of Sciences." The "Pontifical Academy of Sciences" has been around since 1940 and includes some Nobel Prize winners. Christian DeDuve comes to mind and an old colleague of mine from Washington University in St Louis, Rita Levi-Montalcini. As a matter of fact deDuve dismissed me as a mystic in a private letter long ago. If I'm a mystic, Richard Dawkins is the second coming. Its the Funamentalists and the Darwinians that are mystics, postulating things they can't even demonstrate. I would love to believe in a living caring God. I'm just waiting for a scintilla of evidence for his existence. All that matters is what can be demonstrated at the laboratory bench. What individuals believe means absolutely nothing. You may write that down too. John Davison
“Since God is apparently dead as a hammer” Indeed it's going to be hard to break this news to the countless believers across the globe who believe he works in their lives, personally, on a daily basis. But perhaps this isn't an appropriate topic for this forum. Bombadill
"Since God is apparently dead as a hammer" Maybe you should write your local Bishop or whatever and let him know that God is dead. I'm sure it'll be news to him. DaveScot
What I was suggesting is worth further consideration is transposons causing heritable acquired characters. Position effect having real significance is a given. Sorry if I wasn't clear enough. Mobile elements and their remnants including transposons and endogenous retroviruses riddle the human genome composing some 45% of the total. They're still active today. Endogenous retroviruses have not only the ability to cause Lamarckian inheritance in one host, but since they're infectious they can rapidly ripple through whole populations and cause radical change in an entire species in a single generation. DaveScot
I gave both the Longhorn and Aggie cheerleaders the opportunity to compete in my presence to see who was better. A couple wrote back and said they were too busy. That speaks loud and clear to me that neither of those teams has any cheers worth a nickel. Propriety prevents me elaborating on what that leaves twisting in the wind. DaveScot
It is not only worthy of further consideration, it has already been demonstrated many times over. Read my PEH paper again and see if you agree. There is absolutely nothing in the Darwinian mythology that ever had anything to do with creative evolution. Do you know what that leaves for an alternative? I'll tell you what it leaves. Since God is apparently dead as a hammer, it leaves the Prescribed Evolutionary Hypothesis, that's what it leaves. Got that? Write that down. I am gettimg tired of all this nonsense. The best defence is a good offence and I am spoiling for a fight. "War, God help me, I love it so." General George S. Patton, like Einstein and myself a convinced predestinationist. Paraphrasing the Bard: Conscience doth make cowards of the whole damn bunch of those that are congenitally deaf to Einstein's "music of the spheres." I have heard that music more than once in my half century as a physiologist. Like Richard P. Feynman said: "Scientific discovery is like a religious experience." I gave both sides an opportunity to hold forth and heard nothing in response. That speaks loud and clear to me that no one else has an hypothesis worth a nickel to explain the greatest mystery in all of science. How do you like them skewered half-baked nincompoops left slowly twisting in the wind? John Davison
Near half the genome is composed of transposons. http://en.wikipedia.org/wiki/Transposon By definition any changes they make, and they appear to make a lot given the percentage of the genome that is transposable, are Lamarckian and happen in germ cells as well as any other cell with DNA in it which I guess only rules out red blood cells. Seems to me that if position effect is of real significance, and with transposons causing a lot of genetic material to be repositioned, that might be something worth further consideration. DaveScot
I am unimpressed with the YEC perspective or any other kind of fundamentalism. I also see no evidence for Lamarckian effects of any real significance. If others do that is fine with me. Whatever floats your boat. John Davison
"For multicellular organisms, how could genetic modification of the germ line occur post hoc?" Transposons and epigenetics. Read just about anything by Scott F. Gilbert. I don't have the reference on me, but he mentions a paper which shows an organism that develops a hardened neck if it is conceived in an environment where it predator has been. If several successive generations are conceived in such an environment, then the change becomes a fixed feature. Likewise, look at the complex adaptations of the orchid family for symbiosis. These are likely the results of predefined genetic modifications in response to nearby insects. Also, look at these papers by YEC Todd Wood: http://www.grisda.org/origins/52007.pdf http://www.grisda.org/origins/54005.pdf johnnyb
I am no longer concerned with whether anyone agrees with me or not or with the views of my many distinguished sources. If someone disagrees they have the responsibility to explain what it is they find unacceptable. I am happy to defend anything I have ever published but I have no intention of responding favorably to comments which indicate my correspondent has no convictions himself. I have already been through that many many times, most recently when I demonstrated that no one was willing to offer HIS version of the MECHANISM of organic evolution. Well I have offered MINE and I stand by it. Got that? Write that down. Now ask and I will try to answer. John Davison
Feederbottom, whoever that really is. Why not Bottomfeeder? You don't eat with your bottom do you? I certainly I hope not. Why must people use aliases? That such a policy was ever begun escapes me. I have a good long term but a lousy short time memory. I do have pearls of wisdom scattered about and can usually find them. Perhaps you would be willing to tell me exactly what cannot agree with and why. Just to say so means nothing to me, absolutley nothing. You may write that down. John Davison
I must say, John, I rarely aggree with what you say, but I love how you pepper your discourse with quotes. Are you pulling these from a quote book on your desk? Feederbottom
Xavier Heavens no you certainly can't make any such assumption. I believe in reproductive continuity throughout the history of life. The only reservation I have relates to the number of times life originated. Nobody knows and don't ever let anybody tell you otherwise. All we know is THAT life originated and I personally regard it as inconceivable that could ever have occurred by chance. Evolution did not occur through the mechanisms we now see operating in contemporary foms which are of two basic types, either through asexual reproduction which tends to be clonal or through sexual means which I do not believe had anything to do with creative evolution. Quite the contrary, I believe sexual reproduction like Natural Selection is entirely anti-evolutionary. I have repeatedly asked for examples of sexually mediated evolution and been greeted with silence. In 1984 I offered the Semi-meiotic Hypothesis as a potential explanation and it remains untested or even unacknowledged for that matter. I recommend that you read my unpublished "An Evolutionary Manifesto: A New Hypothesis For Organic Change." You will find it at ISCID's forum where it was presented for a lengthy discussion a long time ago. I am not prepared to recount all that here when it is available elsewhere. After you have read and digested it I will be happy to respond to any questions. Let me say that I am a convinced creationist but not of the sectarian variety. I do not require that a personal God be involved in any aspect of science and in fact regard such as a hindrance to our understanding. I also regard Intelligent Design as self-evident and a mandatory assumption for our understanding of both ontogeny and phylogeny. For all practical purposes, yes, I do assume that contemporary species are immutable except for the potential for the production of subspecies and varieties. Many life forms are incapapble even of that. I will remain skeptical until it is demonstrated, under controlled conditions, that sexual reproduction can sustain a creative evolutionary event. That has never been done and quite frankly I regard it as impossible. We do not see evolution in action to day. We see only the terminal products of a past evolution which ended long ago, rwo million years ago at the genus level and somewhat more recently at the species level. The changes we now observe are trivial and have nothing to do with creative evolution. If a new life form appears I am confident it will prove not to have been produced through the agency of sexual reproduction. Sexual reproduction is much to anti-evolutionary and conservative to be involved in creative evolution, a phenomenon no longer taking place. Imcidentaly I am not the only one who believes evolution is finished. Robert Broom, Pierre Grasse and, of all people. Julian Huxley thought the same and said as much. So "don't blame me" as the old ballad proclaims. Blame my sources as well, some of the finest evolutionary scholars of all time. All I have added is what brought it to a standstill, the independent invention many times of sexual reproduction. Thank you for your interest. "It is undesirable to believe a proposition when there is no ground whatsoever for believing it to be true." Bertrand Russell So much for Darwinism. John Davison
Thanks for your response, Dr Davison. I see practical (and ethical should anyone wish to consider homo sapiens) problems with your definition of species. How could, say the African and Indian elephant (to take an extreme example) be tested, if it requires two generations to test? Is not the Ernst Mayr definition (species are "groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups") a more workable definition? (Though both will only work for organisms that reproduce sexually.) Can I assume, that, for you, speciation never occurred, and species are immutable, having been pre-programmed in some way? Xavier
In my first paragraph it should be ambiguous not unambiguous. Sorry about that. John Davison
Kavier The only acceptable criterion for species difference is the physiological one that tests to see if the hybrid is fertile or not. If the hybrid is sterile like the mule for example it establishes that the horse and the donkey are separate species. This criterion was proposed by a Darwinian by the way, Theodosius Dobzhansky, and I agree with it entirely. If two forms choose not to interbreed it must be tested by sperm transfer by the experimentalist. I don't believe this criterion has ever yielded unambiguous results. Fertile hybrids indicate subspecies or varieties and nothing more. That seems to be already established for Darwin's precious finches. I do not subscribe to Margulis' explanation for the origin of the metazoa. it is not necessary to do so. I still predict that the cross between a Chihuahua and a Great Dane will prove to produce a fertile product in either direction and probably would not even require assistance at delivery. I would further predict that if the bitch were the Dane she would deliver a great many pups while if the bitch were the Chihuahua, there would probably be a single pup. Winge, in his book "Inheritance in Dogs" described the result of a spontaneous cross between a St Bernard sire and Dachshund bitch who delivered a fertile single pup. This "hybrid" had only one problem. She had inherited the large size from the sire and the short legs from the bitch so her belly dragged on the ground during her pregnancy and had to be protected by towels. her name was "Rollmops." One must never underestimate the power of regulation in embryonic development. Why don't the Darwinians perform this experiment. Surely there is a Darwinian veterinarian somewhere willing to do the necessary sperm transfer assumning that might even be necessary. I am willing to bet that a Great Dane bitch could be successfully impregnated by a properly aroused Chihuahua son of a bitch with very little if any assistance. The reverse might prove to be problematical but it wasn't for the cross I earlier mentioned. Let's get cracking folks and start doing experiments. The Darwinians aren't going to do it. They are afraid to. As for Lynn Margulis, I do not accept her notion of prokaryote fusions either. It has never been demonstrated and, in accord with the PEH, it is not required either. The mitochondrion and the bacterium may simply be reading the same or very similar "blueprints," that were already there long before eukaryotes even appeared. I was amazed when, in a private email, William Provine trotted out dog varieties as an example of evolution in progress. That put a screeching halt to any further correspondence. I hope you can understand why. John Davison
it remains conceivable that Lamarckian devices could have been of importance, perhaps even of great significance, in the past. Are you suggesting something other than horizontal gene transfer, or endosymbiosis (after Margulis), and if so, could you give more details? For multicellular organisms, how could genetic modification of the germ line occur post hoc? While there is no question that varieties can be produced through artificial selection, to the best of my knowledge such attempts have as yet never successfully exceeded the species barrier. What would be acceptable to you as a definition for "species"? There does not seem to be a universally agreed one among scientists. Xavier

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