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Author | Topic: New theory about evolution between creationism and evolution. | |||||||||||||||||||||||
zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
"There is, on one hand, a randomness as to where and when a mutation will occur. ... On the other hand, the term "randomness" as applied to mutation often refers to the lack of correspondence of phenotypic effect with the stimulus and with the actual or the adaptive direction of evolution. ... It is a well known fact, emphasized over and over again in discussions of genetics and evolution, that the vast majority of known mutations are inadaptive. ... " This suggests very strongly that what Simpson means by adaptive mutation is not a directed mutation in response to a specific environmental stimulus but rather simply a beneficial mutation, one that helps the organism adapt to its new environment. The opposite being an inadaptive mutation that doesn't contribute to such adaptation. I think it is quite clear what Simpson means by adaptive mutations in the following passages, taken from Wilking's article: "This sort of limitation and the fact that different mutations may have widely and characteristically different rates of incidence show that mutations are not random in the full and usual sense of the word or in the way that some early Darwinists considered as fully random the variation available for natural selection. I believe that the, in this sense, nonrandom nature of mutation has had a profound influence on the diversity of life and on the extent and character of adaptations. This influence is sometimes overlooked, probably because almost everyone speaks of mutations as random, which they are in other senses of the word. A population in process of adapting to chnage in its environment or to an environment new to it may be expected to have some adaptive instability. It may be adapting by utilization of expressed and potential variability but it may also be adapting in part by adaptive mutations. Sooner or later and in some changes of adapation, if it is true that mutation is the ultimate source of material for evolution, adaptive mutation must be involved. In spite of the general "randomness" of mutation in the special senses noted, there is adequate evidence that aadaptive mutations are often available under such circumstances. "Simpson wouldn't go to such pains in defining adaptive mutations, if it was only for simply beneficial mutations. All we know them so well. I think it might be usefull as well to quote Dawkins from the same article: "It is grindingly, creakingly, obvious that, if Darwinism were really a theory of chance, it couldn't work. [Dawkins 1996: 67]Darwinism is widely misunderstood as a theory of pure chance. Mustn't it have done something to provoke this canard? Well, yes, there is something behind the misunderstood rumour, a feeble basis to the distortion. one stage in the Darwinian process is indeed a chance process -- mutation. Mutation is the process by which fresh genetic variation is offered up for selection and it is usually described as random. But Darwinians make the fuss they do about the 'randomness' of mutation only in order to contrast it to the non-randomness of selection. It is not necessary that mutation should be random for natural selection to work. Selection can still do its work whether mutation is directed or not. Emphasizing that mutation can be random is our way of calling attention to the crucial fact that, by contrast, selection is sublimely and quintessentially non-random. It is ironic that this emphasis on the contrast between mutation and the non-randomness of selection has led people to think that the whole theory is a theory of chance. Even mutations are, as a matter of fact, non-random in various senses, although these senses aren't relevant to our discussion because they don't contribute constructively to the improbable perfection of organisms. For example, mutations have well-understood physical causes, and to this extent they are non-random. ... the great majority of mutations, however caused, are random with respect to quality, and that means they are usually bad because there are more ways of getting worse than of getting better. [Dawkins 1996:70-71] "
I still have no idea what you are trying to say when you talk about the predictive value of mutations, it seems to be an essentially meaningless term as you use it.
Any theory so widely but not so scientifically, in my opinion, established as it is thought, as the random mutation theory is, should have predicted and verified some facts. This is what i mean by predictive value. Edited by zi ko, : No reason given. Edited by zi ko, : No reason given.
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
Simpson wouldn't go to such pains in defining adaptive mutations, if it was only for simply beneficial mutations. All we know them so well.
Simpson is defining adaptive mutations as increasing the random mutation rate in times of stress. The mutations are still random with respect to fitness, the opposite of guided mutations. Here is some background on adaptive mutations. One of the important experiments dealing with adaptive mutations was on lac revertants. They were trying to use the Luria-Delbruck experimental design in a situation where the challenge was not immediately lethal. They chose a bacterial strain that had a knockout mutation in the lac gene which is responsible for the metabolism of lactose. Then then put this strain on plates where the only carbon source was lactose. They then looked for mutations in the lac gene which resotored lactase activity. When the counted the number of lac revertants they found that there were many more than they expected. This opened up the possibility that the bacteria were specifically mutating the lac gene in order to fix that gene. Further experiments disproved this notion, and these experiments led to the discovery of the SOS response. The response is triggered by DNA damage, not by the presence of lactose. This response upregulates the production of error prone polymerases and increases the rate of gene duplication and recombination. The random mutation rate increases, but the mutations are not guided to the lac gene. Nowhere in the process does the bacteria sense the presence of lactose and then specifically mutate the lac gene. This is the type of system that Simpson is talking about. He is talking about the non-random nature of the random mutation rate. Nowhere is Simpson supporting your idea of guided mutations.
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zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
I am able to talk about it by actually demonstrating it, as shown in the Luria-Delbruck and Lederberg experiments. In these experiments, the beneficial mutations occurred without the bacteria needing those mutations. They were OBSERVED to be random with respect to fitness.
These experiments just demonstate a limited momen of evolution lifeI quote GOULD from WILKINS article (evolution and chance): "Thus, if you wish to understand patterns of long historical sequences, pray for randomness." If this is so, why "randomness" should be seen as random? Nature or God could just use it. if this is the case, and it seems it is. The lottery is random with respect to the tickets just as mutations are random with respect fitness. "It is grindingly, creakingly, obvious that, if Darwinism were really a theory of chance, it couldn't work." [Dawkins 1996: 67]"...It is not necessary that mutation should be random for natural selection to work. Selection can still do its work whether mutation is directed or not. Emphasizing that mutation can be random is our way of calling attention to the crucial fact that, by contrast, selection is sublimely and quintessentially non-random. It is ironic that this emphasis on the contrast between mutation and the non-randomness of selection has led people to think that the whole theory is a theory of chance." [Dawkins] Edited by zi ko, : No reason given. Edited by zi ko, : No reason given.
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Wounded King Member (Idle past 289 days) Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
we know them so well. Yes, we do, but Simpson was writing this in 1953. The structure of DNA was only elucidated that year, Cairns wouldn't publish his research on 'adaptive' mutation for another 35 years and the Lederbergs had only just demonstrated very clearly that adaptive, as in beneficial, mutations for one environment arose in environments for which they were not adaptive/beneficial. Indeed the Lederbergs' paper consistently (Lederberg and Lederberg, 1951 PDF) refers to the mutations as adaptive and does not use the term beneficial once. The distinction they draw is between pre-adaptive mutations and directed adaptive mutations. I don't think a single part of the rest of the quote argues against this interpretation and indeed it is much more consistent with this interpretation than that of Simpson meaning directed mutation.
Any theory so widely but not so scientifically, in my opinion, established as it is thought, as the random mutation theory is, should have predicted and verified some facts. It has, in fact the Lederberg plate experiment has been presented as an example of just such a case where the assumption of mutations random for fitness predicts that resistant colonies will be discreet and clonal with representation in both the selected and non-selected replicates while an adaptive response would predict a random distribution of resistant cells/colonies arising on the selected plate and not the un-selected. The fact that you are monumentally ignorant is not any sort of argument. As I've said before your theory only differs from the standard one in its uniquely insane regions which you seem to have chosen to no longer discuss. The rest of it seems to be made up of this sort of meaningless semantic drivel where you insist of confusing different usages of the term random. It is remarkable since the Wilkins article you are quoting so extensively is specifically designed to counter such confusion. TTFN, WK
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Wounded King Member (Idle past 289 days) Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
Simpson is defining adaptive mutations as increasing the random mutation rate in times of stress. I think you are ceding too much to Zi Ko's interpretation. What Simpson draws a distinction between is adaptation utilising already existant heritable standing variation including in the population and heritable variation that arises after some environmental challenge as a de novo adaptive mutation, what Lederberg differentiated as pre- and post-adaptive mutations. He stipulates that he thinks both exist but I'm not sure there is anything more to be drawn from the quoted material here. He never suggests anywhere that there is any sort of change in mutation rate due to stress. I'd be interested to know where you think he does. TTFN, WK
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
He never suggests anywhere that there is any sort of change in mutation rate due to stress. I'd be interested to know where you think he does. I was assuming that Simpson was using the modern term which is probably a bad assumption to make. If Simpson is merely talking about phenotype plasticity then Zi ko is really barking up the wrong tree.
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
These experiments just demonstate a limited momen of evolution life
They demonstrate that mutations are random with respect to fitness, the very thing you are trying to deny.
If this is so, why "randomness" should be seen as random? Nature or God could just use it.
Or it could be filtered through natural selection, just as we observe.
"...It is not necessary that mutation should be random for natural selection to work. Selection can still do its work whether mutation is directed or not. Emphasizing that mutation can be random is our way of calling attention to the crucial fact that, by contrast, selection is sublimely and quintessentially non-random. It is ironic that this emphasis on the contrast between mutation and the non-randomness of selection has led people to think that the whole theory is a theory of chance." I think you should reread that quote and think about it.
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zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
It has, in fact the Lederberg plate experiment has been presented as an example of just such a case where the assumption of mutations random for fitness predicts that resistant colonies will be discreet and clonal with representation in both the selected and non-selected replicates while an adaptive response would predict a random distribution of resistant cells/colonies arising on the selected plate and not the un-selected. The Lederberg experiment:The evolution mechanism in one cell organisms is an instance in the evolution history, not the whole of it. You cannot draw conclusions for the multicellular organisms, wrhere evolution mechanims are surely more complex. I think we need an example of predictive value of random mutations in multicellular organisms too. Random mutations is, somebody can easily say, a special for the case choice between other mechanisms by nature. As I've said before your theory only differs from the standard one in its uniquely insane regions which you seem to have chosen to no longer discuss.
The concept of of the organism-environment information interchange is very much connected with the the concept of neural's system and for the same reason of empathy's intervention in evolution process .
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zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
Or it could be filtered through natural selection, just as we observe.
So ,it is a matter of choice of belief, as many times i had been saying.
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
The evolution mechanism in one cell organisms is an instance in the evolution history, not the whole of it. You cannot draw conclusions for the multicellular organisms, wrhere evolution mechanims are surely more complex. I think we need an example of predictive value of random mutations in multicellular organisms too.
This thread is about your theory of evolution. Where are those predictions?
Random mutations is, somebody can easily say, a special for the case choice between other mechanisms by nature.
Random mutations is the rule. It is the only mechanism for producing heritable variation that I am aware of. If you disagree, then now would be the time to cite evidence.
The concept of of the organism-environment information interchange is very much connected with the the concept of neural's system and for the same reason of empathy's intervention in evolution process . You need more than concepts. You need evidence. Where is it?
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
So ,it is a matter of choice of belief, as many times i had been saying.
It is a matter of fact and observation. We observe that mutations are random with respect to fitness. We observe that these random mutations filter through natural selection.
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zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
It is a matter of fact and observation. We observe that mutations are random with respect to fitness.
It applies only to mono-cell organisms.It would be more scientific if you mention that and even more responsible if you had added that this "randomness" maybe is part of nature's or God's plan.Surely it is not only your fault. I discern a fiddling with of the whole evolutional community, who wand to attach to the evolutional process an aura of moral meaning. Edited by zi ko, : No reason given.
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Wounded King Member (Idle past 289 days) Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
It applies only to mono-cell organisms. No, it doesn't. Just repeating something that isn't true doesn't magically make it true. It is easier to demonstrate in unicellular organisms because they have very short generation time and can be cultured very simply but there are no studies in metazoa that support directed mutation and all the existing studies seem consistent with mutation being random in terms of their phenotypic/fitness effects. The real problem is that except in very extreme selective environments it is hard to detect any signature of something like directed evolution. It isn't impossible that there is a tiny signal of directed mutation lost in the vast ocean of random mutational noise, but there is no evidence in the metazoa to support it.
It would be more scientific if you mention that No it wouldn't, it would be lying. Now I believe I have pointed out before that somewhere where it would be germane to suggest that all the evidence, and there isn't much of it, comes from bacterial/unicellular examples is for the sort of directed mutations you have been promoting. You have yet to articulate even the most sketchy outline for how your theoretical system could overcome the germ/soma division in more complex multicellular animals.
I discern a fiddling with of the whole evolutional community, who wand to attach to the evolutional process an aura of moral meaning. That you see things that aren't there is unlikely to surprise anyone at this late stage in the debate. TTFN, WK
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Taq Member Posts: 10302 Joined: Member Rating: 7.1 |
It applies only to mono-cell organisms. Evidence please.
It would be more scientific if you mention that and even more responsible if you had added that this "randomness" maybe is part of nature's or God's plan.Surely it is not only your fault. It applies to all DNA based life. All life is exposed to mutagens, random mistakes by polymerases, indels, recombination events, and exogenous insertion of repetitive elements (e.g. transposons). We can see this in the divergence of non-coding DNA between species. The process of mutation in ALL life produces deleterious, neutral, and beneficial effects. Also, I have yet see evidence of any god or a plan set by this unevidenced god. Why would I include something for which there is no evidence?
I discern a fiddling with of the whole evolutional community, who wand to attach to the evolutional process an aura of moral meaning. So says the person who thinks, without evidence, that there is a supernatural plan at work in evolution. You are projecting.
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zi ko Member (Idle past 3876 days) Posts: 578 Joined: |
all the existing studies seem consistent with mutation being random in terms of their phenotypic/fitness effects.
If i am right, i don't think you ever mention any study in metazoa to prove random mutations. Just to prevent any recycling of old arguments, these studies must specifically state that their results could not be explained by environmentally directed mutations.
It isn't impossible that there is a tiny signal of directed mutation lost in the vast ocean of random mutational noise, but there is no evidence in the metazoa to support it.
Existence even of tiny signal of directed mutations, as you say, it shows that there is , never mind how rare it is, the mechanism to suceed it. So why you so insistantly used to ask me to present that mechanism?In spite of this random mutation noise the evidence is negligible. You have yet to articulate even the most sketchy outline for how your theoretical system could overcome the germ/soma division in more complex multicellular animals.
I suggest neural system to bridge this division.That you see things that aren't there is unlikely to surprise anyone at this late stage in the debate. If you remain unable to bring the needed evidence, i insist there is fiddling with.
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