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Epigenetic Inheritance: Can Evolution Adapt?

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Given how routinely evolution fails to explain biology, it is remarkable that scientists still believe in the nineteenth century idea. One of the many problems areas is adaptation. Evolution holds that populations adapt to environmental pressures via the natural selection of blind variations. If more fur is needed, and some individuals accidentally are endowed with mutations that confer a thicker coat of fur, then those individuals will have greater survival and reproduction rates. The thicker fur mutation will then become common in the population.

This is the evolutionary notion of change. It is not what we find in biology. Under the hood, biology reveals far more complex and intelligent mechanisms for change, collectively referred to as epigenetic inheritance. You can read more about the challenge that this form of inheritance poses for evolution here. The take home message is that adaptation is routinely found to be not blind, but rather responsive to environmental pressures. The fur becomes thicker not by accident, but via cellular mechanisms responding to a need.

There is still much to learn about this phenomenal built-in adaptation capability, but it now is clear, and has been for many years, that epigenetic inheritance is a dramatic departure from evolutionary expectations. Indeed, this sort of adaptation is closer to the ideas of the long disgraced French naturalist Jean-Baptiste Lamarck (1744-1829). Lamarck’s idea was that offspring inherit traits or characteristics that were acquired by the parents. Although epigenetic inheritance is far more complex than anything Lamarck imagined, he was remarkably close to what is now being discovered. You can see a recent review of what has been learned here. Only a few years ago positive references to Lamarck drew heated response. Such ideas were not tolerated. Now his name appears regularly in the epigenetics literature.

This leaves evolutionists in an awkward position, to say the least.

Continue reading here.

Comments
Mark Frank:
“Result X is wildly improbable based on random permutations of DNA therefore X was designed” is even not valid even if the premise were true. Inheritance is not just DNA, and inheritance may not be entirely random. And it all happen without design.
If it's not random, and also happened without design, then where did this system of innovative and inherited self-improvement come from? From some unknown natural law that wants threatened water fleas to have spikes? Between chance, design, and natural laws, what am I leaving out?ScottAndrews
June 11, 2009
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should say, Darwin himself correctly predicted it.Khan
June 11, 2009
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Cornelius,
But this sort of dismissal based on a word-smithing problem is uncharitable. Here is an uncontroversial failed prediction, and you focus on an ambiguity in the introduction that has no bearing on the prediction itself or its falsification.
that's the problem, it is not an uncontroversial failed prediction- Darwin himself predicted it. or do you not consider Darwin an "evolutionist"?Khan
June 11, 2009
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A couple of small contributions to this exciting debate. Let's be clear - Epigenetics is not the same thing as Lamarckism. This has been touched on above but not I think made clear. Epigenetics is simple inheritance by methods other than DNA. Lamarckism is inheritance of acquired characteristics by any method - including DNA. Cornelius web site and post seem to muddle the two. It appears that both epigenetics and Lamarckism have more of a role than biologists of 50 years ago realised. Nevertheless these are still natural not designed processes. Scientists looked at the evidence and altered the hypothesis in the light of the data - no design needed. What this does show is that the deduction that goes: "Result X is wildly improbable based on random permutations of DNA therefore X was designed" is even not valid even if the premise were true. Inheritance is not just DNA, and inheritance may not be entirely random. And it all happen without design.Mark Frank
June 11, 2009
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Mr Joseph, How can one test the premise that a bacterial flagellum can evolve from a population that never had one via an accumulation of genetic accidents? By trying to answer that question you will see the hopelessness of your position. Take populations of sessile bacteria, devise a protocol that rewards motility. Run experiment. No guarantee you will get the same flagellar structure of course! No need for hopelessness. :)Nakashima
June 11, 2009
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Mr Joseph, At least you are getting your definitioins from a better source now! Please go on and trust the rest of Allen says. Behavior is part of the phenotype built by the genotype. That is why Dawkins' book on the subject is called "The Extended Phenotype". Are you saying that you do not believe that animal behavior has a genetically determined component? Spiders are taught to spin webs by their mothers, or by small angels whispering in their ears?Nakashima
June 11, 2009
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iconofid:
All branches of science are littered with failed hypotheses, as you know.
And the alleged "theory" of evolution can't even muster a testable hypothesis. For example: How can one test the premise that a bacterial flagellum can evolve from a population that never had one via an accumulation of genetic accidents? By trying to answer that question you will see the hopelessness of your position. And by ignoring my question you will prove my point.Joseph
June 11, 2009
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Very different cells and organisms with the SAME DNA? Oh yeah natural selection, no problem.
No, that is called differentiation and development.
I know what it is. I also know that it is a form of epigenetics. And it is a fact that evos just call on natural selection to explain it.
You can 150 cell types in your body and they all have the same DNA.
And my point is that evos point to NS as an "explanation". That is without any evidentiary support.Joseph
June 11, 2009
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To Winston and Nakashima,
“Natural selection is therefore a result of three processes, as first described by Darwin: Variation Inheritance Fecundity which together result in non-random, unequal survival and reproduction of individuals, which results in changes in the phenotypes present in populations of organisms over time.”- Allen McNeil
Notice that "behavior" is NOT part of natural selection. IOW even if some organism has a genetic advantage that does NOT necessarily mean it has the best chance for survival. IOW natural selection is made even more trivial- pretty much a do-nothing mechanism.Joseph
June 11, 2009
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Khan:
the only way anyone is going to take you seriously is if you present accurate information. this is anything but that: Charles Darwin’s theory of evolution was a radical break from Lamarckianism, or any idea that biological change occurs in response to need in any case, the website is full of mistakes and distortions like that. for example, in “SImple beginnings” you cite Michael Sherman’s paper in Cell Cycle as if it was representative of a prominent idea among evolutionary biologists. In 2 years, it has not been cited once in a peer-reviewed paper. [...] you need to be much more careful with your scholarship.
Full of mistakes and distortions? Let's see, you found two paragraphs you didn't like, which have absolutely no bearing on the respective falsified predictions, and now the entire document is "full of mistakes and distortions." If this was just you Khan it might be funny, but this is quite typical for evolutionists. I see this repeatedly. Evolutionists complain about whatever they can, and avoid the main points of the criticism. We've already discussed your first complaint. I agree with you that some clarification will help to indicate it is 20th c. evolution, not 19th c. evolution that makes the break. But a distortion?? You've got to be kidding me. It is clear in the remainder of the section that the failed prediction arises from neo Darwinism, and furthermore the ambiguity has absolutely no effect on the point of the section. When I wrote that section I had more recent evolutionists in mind rather than Darwin, and failed to read that sentence with Darwin in mind, as you did. You had not read the Introduction, and took the website to be addressing Darwin rather than evolution more generally. Fair enough, that's an understandable mistake given the name of the website. And your feedback is helpful. But this sort of dismissal based on a word-smithing problem is uncharitable. Here is an uncontroversial failed prediction, and you focus on an ambiguity in the introduction that has no bearing on the prediction itself or its falsification. In your second example you say I cite Sherman "as if it was representative of a prominent idea among evolutionary biologists." In fact, I write "The feasibility of this hypothesis may be difficult to determine." It certainly is not a mainstream hypothesis, and I can do more to clarify that further. Your feedback is helpful but, again, this has non bearing on the falsified prediction and certainly is not a distortion. There are evolutionists talking about ideas such as this, there is a paper out in a peer reviewed, respectable journal, and I cited it as an example reaction (which are hard to find by the way for the problem of early complexity). This is a classic example of how evolutionists react to scientific problems.Cornelius Hunter
June 10, 2009
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Indeed. That whole "evolution and nature is unguided and without purpose" thing is a failed hypothesis, after all. Just the way science is! ;) (I kid of course. Such a statement isn't scientific at all - it's metaphysics, and necessarily excluded from the science.)nullasalus
June 10, 2009
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Cornelius Hunter: The purpose of the website is to provide a sample tally of falsified predictions of evolutionary theory (see Section 1), which could be used in support of a larger theory evaluation exercise, for instance, and to explain why evolutionists claim their theory is a fact. Theories aren't facts, Cornelius, by definition. The claim you're probably thinking of "evolution is a fact". And after a brief look at your page, the failed hypotheses you list don't seem to be failed predictions of evolutionary theory, anyway. They are failed hypotheses that would have led to theories within the theory, if successful, or to abiogenesis/chemical evolution theories. All branches of science are littered with failed hypotheses, as you know. It's the nature of the beast!iconofid
June 10, 2009
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More apropos to the discussion, Huxley and Monod did not have access to the research on epigenetic effects and adaptive variability that you cite. It is something of a bait and switch to cite a text from 1953, and then knock it down with current research. The overall point is that Darwin's thesis of evolution through heritable variation and selection is agnostic on the source of variation, and even whether the variation is uniformly or non-uniformly distributed across the heritable material. Your concluding parapgraphs in that section of your web page actually come close to making that clear. While the concept is simple the operational details in real biology are not. Even in these suprising and exceptional areas, there is a clear, naturalistic explanation for the information pathway.Nakashima
June 10, 2009
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Cornelius, the only way anyone is going to take you seriously is if you present accurate information. this is anything but that:
Charles Darwin’s theory of evolution was a radical break from Lamarckianism, or any idea that biological change occurs in response to need
in any case, the website is full of mistakes and distortions like that. for example, in "SImple beginnings" you cite Michael Sherman's paper in Cell Cycle as if it was representative of a prominent idea among evolutionary biologists. In 2 years, it has not been cited once in a peer-reviewed paper. I think the idea of the website is fine (I use many of the examples in my own Evolution class), but you need to be much more careful with your scholarship.Khan
June 10, 2009
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Arthur:
Um, epigenetic changes are every bit as random and haphazard, when it comes to the specific genetic targets of such changes, as so-called genetic changes.
No, epigenetic change is not random.
Just so we are clear, epigenetic changes are not targeted exclusively to the particular locus that may be of adaptive value. The strategy of life when it comes to adaptive changes, be they epigenetic or genetic, is rather akin to carpet bombing - lots of changes, some of which may be of adaptive value but most of which will be of no consequence. It's hard to see how this is friendly to ID. It's quite curious to see people claim that some sorts of heritable variation fall outside of the purview of Darwinism. That's sort of like saying that plants fall outside of the purview of evolution. Just doesn't make sense.Arthur Hunt
June 10, 2009
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Khan:
Darwin hypothesized a modified version of Lamarckism ... I’m sorry, is either of those people named Charles Darwin?
The purpose of the website is to provide a sample tally of falsified predictions of evolutionary theory (see Section 1), which could be used in support of a larger theory evaluation exercise, for instance, and to explain why evolutionists claim their theory is a fact. I don't think Darwin's views on heredity count as particularly important, when it comes to important predictions of the theory. Some predictions do go all the way back to Darwin himself, but some don't. There are of course plenty of false predictions to choose from. I chose the ones I thought were interesting and important.Cornelius Hunter
June 10, 2009
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Cornelius,
No, take a look at the Prediction section in Section 5.2, where you can read representative statements by evolutionists (J. Huxley and Monod). They clearly state that variation is to be random with respect to fitness.
I'm sorry, is either of those people named Charles Darwin? was either of those people even alive when OoS was published? perhaps you might want to include something by the man himself, given that you are explicitly claiming it to be Darwin's prediction.Khan
June 10, 2009
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Cornelius,
At issue here is not the rejection of Lamarckism, per se, but the expectation that biological variation is not responsive to environmental pressures, but rather is random with respect to those pressures (or, is random with respect to fitness).
and, once again, Darwin did not espouse this idea. the players in the modern synthesis did, because they rejected Lamarckism (rightly, given the data at the time). without a mechanism for inheritance, variation in response to need could not be considered a part of evolution. so, in short: 1) Darwin hypothesized a modified version of Lamarckism (including variation being influenced by need) 2)this hypothesis was not supported by any of the experiments performed to test it, and was rightly rejected 3) new data show that in some cases variation may be influenced by need conclusion: Darwin was right. since your website is called "Darwin's predictions", I'm sure you'll be adding something to this effect soon.Khan
June 10, 2009
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Khan:
I thought we just agreed that the prediction is not accurate- Darwin thought use/disuse could be passed down.
No, take a look at the Prediction section in Section 5.2, where you can read representative statements by evolutionists (J. Huxley and Monod). They clearly state that variation is to be random with respect to fitness. http://www.darwinspredictions.com/#_5.2_Biological_variation I appreciate your pointing out my weak description of Darwin's thought which I will clarify, but with neo Darwinism the prediction became more obvious, as indicated with the example statements by Huxley and Monod.Cornelius Hunter
June 10, 2009
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Khan, I mentioned that both forces can be involved (hence why I mentioned their interplay), but if built-in adaptive evolution is the primary method of new trait development, the pattern of trait emergence would be rapid and "horizontal", even if NS was present at the same time. NS would become a secondary effect and would be obscured by the more dominant mode of transmission. Dr. Hunter, Sorry if I got your main point wrong. I did mention the difference between random variation and adaptive variation however. In either case, sorry if I misrepresented you. AtomAtom
June 10, 2009
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Cornelius,
I say “word-smithing” because the prediction itself is certainly accurate (ie, variation is blind to environmental pressures), but with Darwin it is vague, as you point out.
First, I thought we just agreed that the prediction is not accurate- Darwin thought use/disuse could be passed down. Second, I said Darwin was vague in Origin of Species. he develops his ideas of inheritance more fully in his other works. i'll check your website periodically to see how the word smithing goes and offer suggestions. here is one: "While Darwin's quasi-Lamarckian idea of inheritance of acquired characteristics was flatly rejected by biologists in the early 20th century due to an abundance of negative experimental data, recent evidence has shown that it may, in some cases, have merit after all."Khan
June 10, 2009
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There mere continued presence of selection operating at some level in evolutionary theory is not enough to maintain the state some people are arguing for here - just as the mere truth of "some kind of evolution" is not enough to validate all evolutionary perspectives as Darwinism. Lynn Margulis, for example, absolutely accepts "natural selection" plays a role in evolution. And yet the scope of that role, as argued by her, was enough to label her views unorthodox. Though she's not an ID proponent, her case is instructive: Not all views of NS are equal. Some people here are attempting to lower the bar so much they may as well say "So long as organisms die, Darwin was basically right!" It's not sufficient - and people should realize that, much like common descent, "natural selection" still plays a role in the views of various ID-friendly or ID-proposing thinkers (Michael Behe, Michael Denton, Mike Gene - man, what's with all the Mikes?). Does that mean these three are all Darwinian? If so, then "Darwinism" has finally reached the point where it means nothing much at all. If not, then it's clear that the mere presence of selection in a theory simply isn't enough to make it compatible with Darwinism. The existence of mechanisms and states of nature which may innately provide direction - even "natural direction" - to evolution run risk of making evolution look rather more teleological and directed than fundamentally "random" in any meaningful sense. Or, put another way: Not all mechanisms are necessarily the kind that fit well with Darwinism, either scientifically or metaphysically (the latter being particularly hard to defend.)nullasalus
June 10, 2009
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Atom:
I’m guessing Dr. Hunter’s point is this: RV + NS predicts a distribution of variation and speed of transmission different from a built-in adaptive directed evolutionary model. Since they predict different speeds and distributions, the evidence will support one or the other in specific cases (or their interplay.) If adaptive directed evolution explains the facts most of the time, then RV + NS will have to be demoted as the dominant mode of evolution. This is my guess as to what his basic argument is.
Not quite. My point is simply that an important prediction of evolution has been falsified. As I discuss here: http://www.darwinspredictions.com/#_5.2_Biological_variation Khan:
this was not just an evolutionary expectation, but one of all biology, based on rigorous experimentation (e.g. cutting the tails off of of rats for 20 generations and seeing that their offspring still had tails). given those types of data, biologists were absolutely right to reject Lamarckism. or should they have just ignored the data and caused the starvation of an entire country like Lysenko in Russia?
At issue here is not the rejection of Lamarckism, per se, but the expectation that biological variation is not responsive to environmental pressures, but rather is random with respect to those pressures (or, is random with respect to fitness).Cornelius Hunter
June 10, 2009
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Cornelius,
Agreed. My point is merely that yet another evolutionary expectation went wrong.
this was not just an evolutionary expectation, but one of all biology, based on rigorous experimentation (e.g. cutting the tails off of of rats for 20 generations and seeing that their offspring still had tails). given those types of data, biologists were absolutely right to reject Lamarckism. or should they have just ignored the data and caused the starvation of an entire country like Lysenko in Russia?Khan
June 10, 2009
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This following study is clear genetic evidence of the "limited and rapid variation from parent kind" predicted by the Genetic Entropy model: African cichlid fish: a model system in adaptive radiation research: excerpt: "The African cichlid fish radiations are the most diverse extant animal radiations and provide a unique system to test predictions of speciation and adaptive radiation theory(of evolution).-------conclusion of the study?------ the propensity to radiate was significantly higher in lineages whose precursors emerged from more ancient adaptive radiations than in other lineages" http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16846905 Cichlid Fish - Evolution or Variation Within Kind? - Dr. Arthur Jones - video http://www.youtube.com/watch?v=F1TDNHNvZRk In fact the Genetic Entropy model fits this following evidence also: The following article is important in that it is one of the few papers showing the principle of Genetic Entropy being obeyed in the fossil record for Trilobites, over the 270 million year history of their life on earth (Note: the Trilobites appeared abruptly at the base of the Cambrian explosion with no evidence of transmutation from the "very simple" creatures that preceded them, nor is there any evidence that they ever produced anything else besides other trilobites during the entire time they were in the fossil record). Excerpt from article:"From an evolutionary perspective, the more variable a species is, the more raw material natural selection has to operate on,"....(Yet Surprisingly)...."There's hardly any variation in the post-Cambrian," he said. "Even the presence or absence or the kind of ornamentation on the head shield varies within these Cambrian trilobites and doesn't vary in the post-Cambrian trilobites." University of Chicago paleontologist Mark Webster; commenting on the "surprising and unexplained" loss of variation and diversity for trilobites over the 270 million year time span that trilobites were found in the fossil record, prior to their total extinction from the fossil record about 250 million years ago. http://www.terradaily.com/reports/The_Cambrian_Many_Forms_999.html Evolution vs. Trilobites - Prof. Andy McIntosh - video http://www.youtube.com/watch?v=9P-gHO2Vl5gbornagain77
June 10, 2009
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Atom, Your points are more perspicacious than Dr. Hunter's, but still ultimately mistaken. THe simplest way to put it is this: you can not escape natural selection. even if epigenetics is shown to be the main mode of inheritance (very doubtful), selection still has to operate on the machinery responsible for the adaptive variation. This has been a hot topic in evol bio for a few decades now; here is a nice review paper to get you started: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VJ1-4GCXBFD-2&_user=5460004&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000062861&_version=1&_urlVersion=0&_userid=5460004&md5=a0c41a453e75501347fbf544f77ffc19Khan
June 10, 2009
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Arthur:
Um, epigenetic changes are every bit as random and haphazard, when it comes to the specific genetic targets of such changes, as so-called genetic changes.
No, epigenetic change is not random.
If one is going to argue that epigenetic changes are contrary to evolutionary mechanisms,
That is not possible, because evolutionary mechanisms always adapt to the latest findings. We can only compare findings to previous predictions, not current theory. Currently envisioned mechanisms are always capable of explaining biology, just as geocentrists are always capable of explaining physics.
one needs to bring to the table evidence that shows that a particular epigenetic change was aimed at one and only one target, and not to an array of loci, one or more of which happened to provide some advantage. Absent such evidence, then we’re still talking about Darwinism - natural selection acting on random variation.
Right, this is a good example of a new and improved version of evolution, where variation is not blind to environmental pressure. Anon:
from the first edition Origin The eyes of moles and of some burrowing rodents are rudimentary in size, and in some cases are quite covered up by skin and fur. This state of the eyes is probably due to gradual reduction from disuse, but aided perhaps by natural selection.
That's in the 6th ed too. If memory serves, Darwin provides one of his powerful theological arguments a few sentences later, at the end of that passage. Khan:
I’m glad you agree with me. Now, are you going to fix your website? bc it explicitly states there that Darwin rejected Lamarckism.
Yes, some word-smithing is in order, thanks. I say "word-smithing" because the prediction itself is certainly accurate (ie, variation is blind to environmental pressures), but with Darwin it is vague, as you point out. The prediction became clear in the 20th century.
The predictions that epigenetic inheritance falsify are not minor problems that are reasonably explained under evolution. so do you think that epigenetic inheritance falsifies Mendelian inheritance? i see no problem with both co-existing.
Agreed. My point is merely that yet another evolutionary expectation went wrong.Cornelius Hunter
June 10, 2009
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Mr Macchi, Mr Joseph - The reasoning is that withOUT the behavioral change the organism would normally die. But, of course, this behavioral change (which is heritable) is also selectable. Yes, and far from thwarting natural selection, it is simply selecting for something else, the basis of the behavioral trait that allowed survival!Nakashima
June 10, 2009
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Hey guys, Sorry to jump into the middle of the conversation. I think the differences between RV + NS are two-fold, and these may not have been explicitly stated yet. First, adaptive variation is not random with respect to fitness; it is directed at improving fitness. So if we find variation triggered by environmental cues, it isn't meaningful to talk about random variation. Secondly, Natural Selection would lose its primary importance in spreading a trait, since the trait could spread without common inheritance, in an environmentally induced "horizontal" method (not to be confused with Lateral Gene Transfer, in which actual genetic information is passed along.) If organisms relied solely on NS to spread a trait from a common ancestor, the process would take a certain number of generations, depending on reproductive rate and other factors. With a directed-adaptive response, it would be possible to fix a new trait in a large population within a single generation. (Meaning, the parents of one generation are exposed to some factor, and all the children in the next generation are then born with a trait. Obviously, this could work much faster than NS.) I'm guessing Dr. Hunter's point is this: RV + NS predicts a distribution of variation and speed of transmission different from a built-in adaptive directed evolutionary model. Since they predict different speeds and distributions, the evidence will support one or the other in specific cases (or their interplay.) If adaptive directed evolution explains the facts most of the time, then RV + NS will have to be demoted as the dominant mode of evolution. This is my guess as to what his basic argument is. If I'm misrepresenting anyone, I apologize. I just wanted to share some thoughts that may clarify the issue. If they muddle it, please disregard. AtomAtom
June 10, 2009
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Mr Joseph, Very different cells and organisms with the SAME DNA? Oh yeah natural selection, no problem. No, that is called differentiation and development. You can 150 cell types in your body and they all have the same DNA.Nakashima
June 10, 2009
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