What is the mechanism that prevents microevolution to become macroevolution?

Then here is where he is not understanding what I'm talking about because diversity at the level of the population is expected, while genetic diversity decreases. {Edit: Realizing the hazard of the term "diversity" in this context. What I mean is change. Change at the level of the population. observable change, change in the phenotype} Greater range of genotypes means a greater range of phenotypes doesn't it? I may have the technical picture off here somehow but I think this is just another way of saying what I'm saying. Because there are different frequencies of alleles, including very possibly a complete absence of some alleles, we now have entirely new combinations that didn't exist in the former combined population. Is this what you are saying?THIS kind of diversity {change} is expected, but it is brought about by a DECREASE in the number of alleles or in what I've been calling genetic diversity, i.e., the number of allelic possibilities in the population. The use of the term "genotype" may bring in a factor that makes this harder to express, but in any case it is describing a change in individuals that is different from what existed in the previous population, and this is at least because of a change in allele frequencies or even a reduction in the number of alleles caused by the elimination of some altogether. Well, what I am saying is the exact opposite. I'm saying that a DECREASE in the number of alleles occurring at specific loci is what brings about more diversity {change} at the level of the population, by which I mean new phenotypes, which I believe implies new genotypes but I haven't been thinking at the level of genotypes exactly except that they have fewer alleles to work with.{IMPORTANT EDIT: OK, I'm realizing there's some terminological confusion here. You are talking about increasing PHENOTYPIC/GENOTYPIC DIVERSITY, but I'm only talking about forming new phenotypes, period, not thinking about how diverse the options may be, more perhaps how striking the observable differences may be {between the phenotypes of the two populations.} The "diversity" is at the allele level and I haven't used the term in any other sense. At the population level, I'm talking about producing new traits -- diversity or numbers of such new traits isn't of any importance in what I'm saying. There may or may not be a lot of them and it doesn't matter. I'm talking about simply creating a new phenotype, period. I assume that a variety of new traits will show up in the new populations from the new frequencies of alleles due to the separation, and that over time, from interbreeding within each population these traits will get more or less blended in the population so that a typical phenotype will come to represent that population, one which differs in a number of traits from the original population, yet of course individuals will still possess some variety of different alleles.AGAIN, in all this discussion diversity of these traits is not the subject. I'm glad I caught this. The subject is confusing enough. Let's stick to diversity of alleles or genetic diversity and simple production of new traits without worrying about how many of them there are.} I've pretty much assumed this without saying it in so many words: That is, in both populations there is an absence of some alleles at a number of loci, caused by this population split. Sorry, you lost me there, got way too technical. I'm trying to stick to the level of simple presence or absence of different alleles plus the proportions in which they occur in the two populations -- for example,no alleles at all for genes 1 2 3 4 and 5,
3 alleles for gene 6
and 10 for gene 7, etc.,as compared to the other population's
5 for gene 1,
3 for gene 2,
2 for gene 3,
1 each for genes 4 and 5,
none for gene 6 and 1 for gene 7.{Edit: This situation could come about from the division of a population that originally contained all of the alleles in both new populations: 5 alleles for gene 1, 3 for gene 2, 2 for gene 3, 1 each for 4 and 5, ALL of these being lost to one of the new populations but retained in the other, and 3 for gene 6, in this case all going to the first population and lost to the second, and 11 for gene 7. I should have had more genes that retained some alleles, to be realistic, say a gene 8 with 12 alleles that split 5 to the first population and 7 to the second and so on}{EDIT: Somehow the above list seems to imply that alleles will only be split and fails to account for the fact that most of them will be shared but in different proportions. Oh well now my brain is too tired to figure out how to express this.}These differences are going to make for very different phenotypes and genotypes in the two populations.You are bringing in other qualities at this point that I think only confuses the issue unnecessarily.EDIT: I'm afraid this post is rather confused because I didn't grasp that you were using "diversity" in such a different sense than I was until the end. I tried to correct it by putting in "change" where you had used "diversity" in that sense, to delineate our two different views, but I'm not sure I succeeded at clarifying anything. I hope I didn't make it less clear.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

You explained the situation to Ben just as I am thinking of it, except for the part where you bring in selection pressures, and I think mutation, though you don't name it. Yes, nothing needed for the change in phenotype except "vastly different distribution of alleles" working their way through the new populations in subsequent generations. This part doesn't seem at all necessary to add. For one thing geographic isolation is more or less implied in the first paragraph, already meeting this requirement. Certainly the less gene flow the more divergence, and in this case, the mere "vastly different distribution of alleles" should explain even dramatic divergence, or even the accumulation of unique alleles. Neither further selection pressures nor mutation (which you didn't name, but perhaps implied in "unique alleles") is needed. Unique alleles are most likely simply alleles that occurred in low frequency in the previous combined population that now have an opportunity to be expressed in the normal pattern of sexual recombination. Selection pressure MIGHT enhance this but it is not needed for this to occur. Mutation is not necessary at all, and whether it might occur or not in any beneficial way is very much open to question. OK, fine, here you're saying what I'm saying. I should have read on. But I'll leave my statement that emphasizes this. Yes, all it takes is isolation.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Ben is the only one who answered fallacycop with a fair representation of what I'm arguing, in his Message 85. Quetzal, in Message 83 is claiming all kinds of things are wrong with my argument and MJFloresta's but he is very far from having demonstrated any such thing. His examples have all tended to support our argument, and he has not made any kind of case whatever for mutation in any of the processes we have discussed.I just wanted to comment on a few things in NosyNed's post. I understand that one problem with pursuing any particular creationist argument is that there are many different creationist arguments and terminological uses, and elements from those may be assumed wrongly to be involved in a particular argument when they are not. This is a case in point. The term "speciation" has been very problematic for creationists because it often is used to imply macroevolution in itself. But speciation is really only variation within the Kind and it would help if creationists would all get on the same page about this. It is a common occurrence, most dramatically demonstrable in domestic breeding programs, but very frequent in nature under all kinds of situations that isolate populations just as domestic breeding does.In fact microevolution IS speciation. Geographic isolation should in fact bring about the genetic changes that lead to speciation, by simply altering the frequency of alleles in the isolated populations. The smaller the new population the more dramatic the change because the fewer alleles there will be available for developing the new phenotypes. This will do it all by itself. I guess by "ongoing changes" you are implying mutation? There is no need to assume mutation in any of this. Geographic isolation would all by itself tend to change the allelic frequencies sufficiently to bring new traits into the population and form new phenotypes.I have no idea what you mean by "ongoing genetic changes which have to happen." You mean this change in allele frequency or mutation or both or what? I also don't know what you mean by "smoothed out" or "can accumulate."I assume no useful mutations in everything I say. I see no need for them to explain any of these processes.Maybe your terms imply the following: With changed allelic frequency you get some new traits appearing in the first generations of a new population. These traits may very well accumulate in the population over time with inbreeding, and over time these traits will get more or less "smoothed out" by being intermingled over and over again, until a phenotype that characterizes that new population emerges in an identifiable way. Perhaps this is what you had in mind. I agree with this picture if so. Yes. I agree with the general point except of course the millions of years part. All of the accumulated differences ARE microevolution, and while mutation keeps being mentioned it's kind of like a third thumb, it has no role in any of this. Ordinary sexual recombination of different frequencies of alleles in isolated populations is all it takes to bring about new phenotypes and even speciation. As I've been trying to show, there is a point at which further change in the ordinary processes of speciation becomes impossible, and this is the barrier to macroevolution and provides the means to define the Kind. If normal sexual recombination of a reduced allelic set (which is the case in domestic breeding and in natural selection and geographic isolation etc) is all it takes to produce new phenotypes, and it is, this demonstrates that the reduced allelic set is the operative principle. Reduced number of alleles means less genetic diversity and this is what brings about phenotypic change all the way to speciation. Taken through many repetitions of the same processes the allelic set will be SO reduced that further change of any kind becomes impossible. This is fortunately a rare occurrence in most species so far, because it is a precursor, not to macroevolution but to extinction. This is what has happened to the cheetah. Again, THIS is the line that defines the Kind, that defines the limit of evolution at the outer edges of microevolution and means that macroevolution simply does not happen. Oh we see that just fine, but it's an illusion if you are really grappling with what goes on in the genetic processes that arrive at speciation. These genetic processes are an inexorable reduction in genetic diversity. This is what brings about new phenotypes and eventually speciation and eventually the extremity at which no further change is possible.You guys get yourselves all confused with this background assumption of mutation that nobody ever demonstrates is really going on but gets tossed into any discussion about population genetics. The actual observed facts of speciation 1) do not require mutation at any point, 2) would even be interfered with by mutation because speciation requires allelic reduction not addition,* and 3) do not in fact show any actual evidence whatever of mutation in anything yet discussed. This is a bogus problem, purely a matter of terminological confusion. "Species" is simply the Latin (or Greek?) word for "Kind." But the way it is used in practice it actually refers to varieties of a Kind, and this is why creationists have had to keep adjusting the terminology. This is true, and this is exactly what I've been doing and have in fact done. What I'm pointing at is the end result of a process that has to be grasped conceptually. It can only be demonstrated in the unfortunate cases of extreme genetic depletion as in the case of the cheetah, and you have to throw out that utterly useless notion that mutations have anything to do with it if you are going to understand what I'm talking about.{Edit: * The only exception to the allelic reduction formula is recombination or gene flow between two separated populations or hybridization, and in this case mutation is also not needed. This will reintroduce formerly lost alleles to the combined population and this will produce new phenotypes. Gene drift is a similar process. Without any mechanisms of selection or isolation or reduction new phenotypes can be produced this way, and ultimately the change may be striking enough to be called a new species. But this is more of a homogenizing and stasis-producing process. I don't see how you would ever get macroevolution out of it. To get macroevolution you need to select, and if you select you reduce numbers of alleles, and that means reduced genetic diversity, and then we are back at what I'm describing above, in other words the utter defeat of any possibility of macroevolution since all the processes that would be needed to bring it about actually make it impossible. Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Just so you know, I'm working on your Message 89 and expect eventually also to get to RAZD's Message 88.Cheers.

I've acknowledged that it does not NECESSARILY require loss, Quetzal. Speciation CAN come about slowly through gene drift or gene flow between separated populations or hybridization, which will also change the phenotype, but the kinds of speciation that lead to anything in the direction of evolution would seem to require population splitting or selection, which ultimately tend toward genetic reduction, and reduction of genetic diversity, the way it happens in domestic breeding. After all, evolutionists commonly define evolution in terms that require natural selection, but this is a process that either severely reduces some alleles in a population or eliminates them altogether while others that are selected as more adaptive are expressed. I've tried to avoid saying *always,* because I'm aware that in many cases ALL the alleles from the original population are likely to be split between the two new populations and that only the frequencies of each will be different, and perhaps this is the typical case. I'm trying to focus on a trend that occurs over time, and that is only dramatically seen in a shorter time period when a very small population is isolated, in which case not merely frequencies of alleles will change but some alleles are likely to be lost to it altogether. It is also most likely going to happen when there are a number of speciation events that split populations as in a ring species, such that the last new population is taking only a few alleles from the previous population which also had fewer of some alleles from previous populations. It can also take more of some and then the previous population will have fewer.However, the fact of divergence which you have noted many times, and which is what makes a ring species a ring species, there being as many phenotypes as there are separated populations, suggests that at least frequency change is to be expected, and mutation is not needed for this to happen, merely different proportions of pre-existing alleles, recessives coming more frequently to expression and that sort of thing. You have not shown this, merely asserted it.

You are apparently talking about diversity of phenotypes when you say "at the level of organisms" but I have been talking about diversity in terms of available alleles only. Alleles don't HAVE to be reduced to produce new phenotypes, this can happen within a population with gene drift or unknown selection of some over others that changes the phenotype over time.But we happen to be talking not about this kind of situation but about ring species, which are defined by the fact that they create new phenotypes that typify each new population that splits from a former population. And this comes about by a change in the proportions of the alleles from that in the former combined population. It does the same thing that selection may do, but it does it in a mechanical way.There is NO INCREASE anywhere in this process, ONLY a change in frequencies of the same alleles, which MAY involve but not NECESSARILY involve, the loss of some alleles altogether. No, I am not. I am saying the opposite. I am saying that phenotypic divergence, which means NEW phenotypes, is produced by reduced GENETIC diversity. If anything this could be more phenotypic diversity because of less genetic diversity, though I don't usually talk about phenotypic "diversity" -- organismal diversity as you put it -- but merely the production of new phenotypes. But I am never talking about a LOSS of phenotypic diversity, though this seems to be what you are saying above.Again I think you are confusing diversity of genetic possibilities with diversity of phenotypic expression. Again, I'm ONLY talking about diversity of genetic possibilities, which is determined by numbers of alleles or availablility of alleles within a population, and this brings about NEW phenotypes which is certainly not a loss of diversity there.And I don't know what you mean by "on a statistical level." Could be but what changes genetically when populations split is allele frequencies, and this is all it takes to produce the new organismal forms. Perhaps this comes about by the creation of new "genetic organization patterns," as you put it, but it's the new allelic frequencies that are doing all of it in any case. And back we go to mutation, and again it's only a hypothetical and not a known. Hey, I'd love to see that this is really possible, that mutation, or at least some form of mutation, really does do this, really does recreate viable alleles that have been lost through such things as a bottleneck event. I've thought many times that this COULD be possible since after all we are talking about chemicals, the making of proteins from chemical codes, but so far I've only seen this asserted as you do above, as a potentiality.And there again is the cheetah, still getting along on one allele per locus over many loci without the benefits such a re-creation process would bestow on it.And again, the usual processes of allelic sorting and recombining are enough in themselves to produce new phenotypes; mutation is simply not needed.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Dang, Crash, I may love you after all, mutation notwithstanding.

OK, I guess I missed that. Perhaps he is right, perhaps whole genes are lost, at least in some speciation events. I'd love to but it's very hard in the same way it is hard for scientists to come up with examples of all the bazillion mutations they assume to be the driving force of evoluation, and even harder of course for us nonscientists because we have to depend on your data, and without the technical knowledge, galling though that is to all concerned. I hope you will forgive us but this is simply the reality of the EvC debate unless more scientifically knowledgeable creationists come along. It's all theory at this point. Well, I am still going to get back to that post and to the link to that article. I've done a little work on it but got distracted by these more recent posts.However, as I recall, you gave no examples of increasing genetic diversity at all, of phenotypic divergence but not increasing genetic diversity. You merely asserted that it was there, the same way you asserted that mutations were behind phenotypic divergence, without proving it.You have given lots of evidence in the form of references, but it doesn't answer what I'm claiming. I don't need a counter-example if it's all a matter of how we are to interpret the facts in the example you gave.In Message 79 you really are only saying that you've proved me wrong by demonstrating "increasing divergence between the two populations" but this is a very odd thing to say if you get what I'm arguing, because that's the whole point I'm making -- we expect increasing divergence (in the phenotype) between the two populations over time simply as a result of the working through of the new allelic frequencies brought about by the split from the original population. So demonstrating increasing divergence between the two populations proves nothing since it isn't in dispute, to say the least -- we are simply accounting for this divergence in different ways, and to this point I have not seen a genuine case made for increasing genetic diversity as the explanation for this. See? As if "increasing divergence" is some kind of evidence against me, although this is exactly what I'm saying is to be expected from my own scenario. Your evidence simply does not prove your explanation of this divergence in terms of increasing genetic diversity. If now you are changing the subject to decrease in genome size, how easy would it be to identify the death of a gene? Honestly, Quetzal, I don't see how you think you have shown this. You simply have NOT shown "increased diversity" if by that you mean GENETIC diversity which is what I mean. But I'll now go look at that link.Edited by Faith, : No reason given.

Why is showing divergence of relevance to our discussion? Why is showing greater genetic divergence across greater distance of relevance to our discussion? Why would selection pressures against the hybrids have anything to do with demonstrating a gradual increase in incompatibility between the two subspecies?, question one, and question two, even if it does, how does the hybrid zone add anything to the ability to demonstrate this: it ought to be demonstrable simply by sampling the two subspecies. In other words, whatever role the hybrids play here, which is the whole point of this article, is completely lost on me. I have no problem whatever with the idea that incipient speciation between the two subspecies is happening, or that speciation may already have happened for that matter. What we need is an explanation for the mechanism that is causing this and I'm arguing for mere change in allelic frequencies with probably a loss of some alleles.I'm no longer at all clear what you are arguing for. I do not see how the hybrid population has anything to do with this speciation process for starters, although it may, but only in a way peculiar to this one example, and I certainly do not see any evidence in anything you said or the article itself says (below) for an "increase in genetic diversity" as an explanation for it. Can you point out where either you or the article, which follows, says this? a) I believe this is begging the question. You seem to be saying that the mere fact of great divergence proves me wrong about how divergence is brought about.b) And again, NONE OF THIS SHOWS THAT "genetic diversity is increased."PLEASE point to where you or this abstract have shown how genetic diversity is increased.Here is the abstract: Please show me in the above where either you or the article argue that increased genetic diversity explains the increasing phenotypic divergence of the two Ensatina subspecies with increasing distance from one another.The mere existence of one identifiable mutation would not prove that increased genetic diversity caused the divergence, and nothing you have said shows that reduced genetic diversity which produces new phenotypes is not the explanation.The abstract is too technical for me to read.

For my purposes this is getting too technical. When we talk about the organismal changes that differentiate one population from another in a ring species, for instance, we are talking about phenotype, and it seems to do well enough for my purposes to keep the focus there. I'm aware that genotype is the coding FOR phenotype, but since it's a more complex level I'd rather stick to phenotype, and I don't see how that's a problem for this discussion. As I answered you, I believe that numbers of available alleles is the basis on which that "more" is built, and it is best to keep the discussion simple if we can. Yes, but this is not necessary to the discussion. All it takes to produce new phenotypes OR genotypes is a new combination of alleles, which can arise even through genetic drift, although this is definitely more likely to happen in the case of a population split. A new combination arises within a population which produces a new phenotype which for some reason is favored and passed on. Note I'm saying this CAN happen. It could be a combination already present in the population that simply becomes favored and then becomes a more frequent type until perhaps eventually it comes to characterize the population as a whole. Gene drift CAN lead to a new population-wide phenotype, perhaps even speciation, and I see no reason to think this requires any more than the usual combinations and frequencies of alleles in the population from generation to generation. This is the only one of all the evolutionary processes of population genetics that I've read about that does not involve a form of population reduction or isolation to bring about phenotypic change or even speciation.This continuing assertion of the need for mutation is simply not demonstrated, it is merely assumed. You underestimate the effect of the mere shuffling of alleles in the normal course of sexual recombination. I have very carefully said this is NOT invariable and the discussion above is a case in point. From the beginning my point has been that this is an overall trend of the processes that bring about speciation, and it may take generations to begin to show allele loss. Even in the case of population splits such as the ring species, alleles are not necessarily lost, at least not in the first split, but they MAY be. All that NEEDS to happen to bring about a new phenotype is a change in the frequencies of the alleles and the split will most likely bring that about as individuals with different alleles sort into the two populations. New traits then arise and over time spread in the new populations until a new phenotype comes to characterize each. Excellent point. Yes, they are ALL novel. In this basic constant production of novelty, one or a few individuals may have a set of traits that becomes favored for some reason or another and spread throughout the population and come to characterize it even to the point of speciation. IN the case of population splits which may eliminate some alleles the new phenotype may be rather dramatically different from the old population. Fine, but genotypes are on the same level as phenotypes in relation to what I'm talking about, since they are the INDIVIDUAL coding for the phenotype. I think you are confusing this subject by bringing in extraneous considerations. I am focusing on allelic diversity which is ALWAYS there and it can be discussed exactly as I'm discussing it. It doesn't take anything more than a change in frequencies of alleles to bring about dramatic phenotypic AND genotypic changes in a population. This is irrelevant to the point I'm trying to make. Please try to keep this simple. We are talking about the processes of speciation that can be observed, and allelic frequencies underlie it all, including the "organization and coordinated expression" thereof as I said in my previous post. Please stick to allele frequencies. Other factors do not have to be brought into this. Allele frequencies alone can accomplish what I'm talking about. It is the only way that is under discussion, and it is sufficient by itself to bring about all the changes in both genotype and phenotype that come to characterize a new population to the point even of speciation. Since the normal processes of allelic shuffling are enough all by themselves to bring about speciation, mutation becomes redundant, and truly, it has NOT been shown to have any role in the production of new phenotypes at any rate that would bring about speciation. It is assumed but it has not been demonstrated. This is adding unnecessary technicalities to this discussion. Yes, of course they are OBSERVED, of course they OCCUR, but their role in speciation is merely assumed, it has not been shown. Most of them don't do anything; others produce diseases, even diseases that survive in the population, and very very very few SEEM to have anything beneficial to confer on a population. And meanwhile there are thousands of other genetic factors that are constantly in operation that DO make a difference in the processes that lead to speciation, all this shuffling of already-present alleles that I've been talking about. I have NOWHERE denied this. I was not talking about their mere occurrence, which is not in doubt, but their character and their function in speciation and their effect on the population at all. Even if it does occur it is apparently a very occasional thing and in actual observed reality hasn't been shown to contribute anything to the actual plight of species on the verge of extinction. Fine, they occur, which I haven't denied, but then the upshot of this is that mutations are useless even if they are in fact occurring, so why do you all make so much of them? However it happens, mutations simply are not having this hugely necessary influence that is so often imputed to them. THANK YOU. That's ALL I'm talking about. If you agree that the usual processes are sufficient, and that mutation is not needed, then we are on the same page. Please let's stay there.I guess I can keep on saying "genotype OR phenotype" since you insist. I guess in the end it really does not make an important difference. Thank you. Theoretically it does not, but in actuality it has not been shown, and everything everybody has said about the actuality of mutations continues to add up to a big lack of contribution of anything of any value to the processes that are said to bring about evolution. Meanwhile the normal processes of allelic shuffling are ongoing and potent in their production of genotypic/phenotypic variations. Is there such a thing as a truly novel protein or a truly novel allele for that matter? And what would guarantee that such novelty would be of any real use? Aren't there enough proteins and alleles already in circulation to float the whole boat of what is actually observed in species variation? So it has been said many times, but when it comes down to discussion of the actual observed occurrences and effects of mutations they simply do not cut the mustard. How could they possibly "contribute important changes to population structure" considering their rarity of occurrence, their usual lack of effect at all, their frequent effect in disease processes and their extremely rare supposedly beneficial effect? Please. This is constantly asserted, but it has not been demonstrated at all. I haven't presented it as evidence against mutations. (Mutations are evidence enough against themselves from what has been said about them.) All I have been saying is that allelic sorting is sufficient to drive all the changes that lead to speciation. If mutation enters into this somewhere, sobeit, but it doesn't change this basic fact.Edited by Faith, : No reason given.

Finally I get to this post. Yes it's all of those things I guess you are saying. I guess there's no way to tell from the kind of mutation it is which effect it is going to have? I mean whether it reverses the order of the bases, or jumps a chromosome or whatever? But whatever they are specifically, junk DNA overall appears to be some sort of genetic graveyard, yes? Well, another question is how much actual coding DNA does bacteria have? Some worm or other small organisms have more than human beings do, correct?But all this is really a side issue. On to the meat of the discussion: Finally, this is the crux of the matter of mutation I believe. It's not that mutations have been OBSERVED to do all the work ascribed to them, it is simply ASSUMED that they do because without them evolution can't explain the ORIGIN of all the alleles already present. Am I reading this right?The creationist answer to your question is that all the alleles and genes in existence have been present since the Creation (and we figure LOTS of them have died, and I think possibly ended up in that junk DNA graveyard). Happens, doesn't it? Either there is an adaptation possible from the assortment of alleles available in the population, or the population goes extinct.But this raises the question how on earth this random unpredictable rare occurrence of useful mutations could possibly be expected to provide the necessary adaptive allele in such a circumstance. You mean as soon as an inhospitable environment is encountered, presto chango abracadabra The Mighty Mutation comes along right on cue and supplies the necessary protection against the environment before it kills off our victim species? Where is there any evidence that such a thing is possible, let alone that it actually occurs? Doesn't this expectation that such a useful thing could be counted on amount to a teleology? That is true. But this is only a problem for evolutionists; it doesn't bother creationists. We know they are sufficient for all the variations we see coming about all the time, all kinds of new breeds. We also figure they are very gradually being reduced in all species as well. Yes, this is exactly what evolution requires, isn't it? For there to be potentially limitless variation, mutation HAS to occur, doesn't it?
I believe you are implicitly acknowledging here that even if there isn't actual proof of mutations bringing about the limitless variation evolution requires, it is assumed that they do, because without them evolution is a dead duck. Yes, but that's focusing on an individual. My mistake I guess since of course if an individual has it then it was passed down. But if you focus on the population at large, it is possible for there to be a rare or recessive allele out there somewhere that gets expressed, especially if the population is greatly reduced, and if there are favorable circumstances, it could even increase in frequency and come to spread in the population, that trait eventually characterizing the majority. Got it. But still, a gene could be rare in a population as a whole, no? But what about complex organisms? There it is not all that easy to rule out the possibility of a rare allele -- Quetzal's orange sock, remember? -- in the population. Rare meaning very low frequency. In complex organisms at least, it appears possible that all kinds of less-than-desirable mutations may spread in the population and not lead to immediate death. This being the case, Crash, isn't it a fair inference from these facts that mutation couldn't possibly be relied upon to supply an adaptive allele to deal with environmental threats? I suppose you are assuming very gradual changes in long time frames here, but even then the rate of mutation of any kind whatever, let alone possibly useful ones, seems astronomically unlikely to turn up one that might provide precisely the adaptive value needed in a particular environmental pinch. In fact if anything borders on "God did it," or sheer magic, this does. It is far easier to assume that the allele(s) for the needed adaptation is already present among the allelic possibilities in the population, having been there all along, and gets selected by the environmental threat itself. If you want to say that mutation put it there in the first place, and it's been there since then, well, then we're back to assuming this because evolution needs it anyway, since it can't be proved to be the case. Far more likely all the genetic possibilities were built in back in Eden. Oh I suppose there could be some mutational effects in here somewhere, for repairing broken genes maybe, restoring lost alleles maybe, but not of a degree that would fuel evolution. And I guess we know so far that the effects are mostly neutral, a far number deleterious, even some that aren't lethal at least right away, and very very few are possibly useful. I find it a bit scary myself that there is so much of it since the vast majority of the changes are not clearly desirable. The neutral ones are a wild card it seems. Nothing in all that shows anything that could be relied on for useful or adaptive changes. But what evolution needs is mutations that contribute alleles that can form viable useful variations, and nothing in any of that whole process you just outlined, which tosses up mostly unknowns and undesirables, suggests such a possibility in reality, except at such an astronomically low probability it's as good as nothing at all. That is true. But this number is still large enough for the number of possible combinations to produce very striking variations. That is quite true, but it is evolution that demands the limitless variations, not creationism. The existing stash of alleles is quite sufficient for enormous variations, even after millennia of attrition due to the Fall. It won't ever produce anything beyond the Kind though. Yay, Crash, that is absolutely correct. Absolutely. Evolution absolutely depends upon mutation. Unfortunately what is actually known of mutations does not bode well for their capacity to work the miracles needed by evolution.Edited by Faith, : No reason given.

I'm not so much pointing to the speciation "event" as to the allelic circumstances that bring it about. Back to the example of the ring species, which is a series of populations that migrated each from the former, in other words sticking to the example that best shows what I'm trying to say, the processes that lead to speciation START with the population split. I'm focusing on the situation of a reduced number of individuals being isolated, so that they stop interbreeding with the former population, or at least mostly stop, and inbreed among themselves. This is what happens in various forms of "evolutionary processes" including selection processes. While some processes such as bottleneck will severely alter allele frequencies, in fact eliminate most of them, in most other circumstances the process is slower, but over time you still get to the point where you have fewer alleles, reduced genetic diversity AND strikingly new phenotypes. In the ring species, the reduction in allelic diversity may not be apparent until the last population in the series. The new species doesn't really emerge until the new allelic situation has worked itself through the new population, and I agree there is no absolute identifiable point when this can be said to have occurred. I note you say "diversity" rather than "genetic diversity" and this makes all the difference, and this ambiguity I think is responsible for much confusion on this subject as people have been using it in different senses and thereby missing my whole point.Diversity at the level of phenotype (or genotype) or at the "organismal" level WILL rise. But this is BECAUSE of BUT, if you DO mean GENETIC diversity "is going to rise" no. Only diversity of phenotypes will rise. And this is BECAUSE there is less genetic diversity.If you are claiming a rise in numbers of alleles, and therefore genetic diversity, has been OBSERVED, nobody has shown this to be the case. It has merely been assumed and asserted. The occasional mutation has been observed, but its role in the processes under discussion could only be negligible. True, you appreciated it early on, thank you.Again that ambiguous use of "diversity." Again, of course we see PHENOTYPIC/GENOTYPIC diversity rising. What I am doing is EXPLAINING this rise in phenotypic diversity by the reduction of ALLELIC diversity.And again, if you mean allelic diversity is rising, this has not been shown to be the case. Odd way to put it but I know what you're trying to say, so thanks. In any case, I think the creationists overturned evolution years ago myself, but anyway.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : bunch of edits to provide indents, signature, various grammatical improvements.Edited by Faith, : Added Edit section in middle.

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1Corinthians 1:25-29: Because the foolishness of God is wiser than men; and the weakness of God is stronger than men. For ye see your calling, brethren, how that not many wise men after the flesh, not many mighty, not many noble, [are called]: But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty; And base things of the world, and things which are despised, hath God chosen, [yea], and things which are not, to bring to nought things that are: That no flesh should glory in his presence.

Crash, great claims are made for mutations, very great claims. Mutations are evoked to explain speciation in all creatures. They are evoked to explain the formation of new phenotypes /genotypes /organismal diversity in ring species or in any species.From what I've been arguing here, it is not needed to produce new phenotypes at all, shuffling of pre-existing alleles alone can explain absolutely everything that has occurred in this process, all the way out to frank speciation.And so far the only experiment you've actually referenced is this one with the bacteria. By the way, is that experiment performed frequently and always with the same results? And I assume you examine the genome of the bacteria before and after the mutation event, so what exactly are you seeing there in the basic genetic stuff? Is it possible to pinpoint the mutation, identify what it did to the DNA, and the protein it codes for and all that?Anyway, I have no problem with the fact that mutation occurs, but I continue to maintain that so far nothing has been shown that comes anywhere near supporting the great claims that are made for it, and quite a bit of evidence that suggests otherwise.I do wonder about the occasional beneficial mutation. EZ suggested that one kind may restore or replace a lost allele. He didn't have evidence, merely hypothesized it, saying that mathematically it is likely. In any case, this is interesting to think about. But even if it occurs, that is not enough beneficial mutation to power evolution, and not even the right kind since it's more like a healing process.And again, what DOES power evolution, microevolution I mean -- meaning the development of new phenotypes -- is the normal processes of gene drift, population splitting, migration, allelic shuffling and often allele loss and so on. Mutation is simply being mentally substituted in the role of these normal processes, being assumed to perform the functions these normal processes perform.Please show me that mutations occur often enough even to make a difference in the development of a new phenotype in a ring species. Well, I know you get mutations. I know sometimes they spread in populations. I don't know what the relevance of getting them in bacteria is to chipmunks. For all I know this is simply an expectable natural form of reproduction and not a mutation of the mistake kind.You've claimed you can do the same sort of experiment in other species, so could you give me a reference to such experiments? What new alleles? I think you are mostly assuming new alleles rather than proving they exist. I mean truly novel chemical coding stuff that codes for something the cell can actually use. You have claimed this happens but all I've seen is processes that would bring up previously suppressed alleles, recessive alleles and so on. Please again reference these experiments. I haven't been impressed with what you've shown so far. OK, big hypothetical there. You say all the pre-existing stuff mutated there. You are merely ASSUMING that it mutated there. I assume it was created there in the very beginning. Well, drat, Crash, this is what I assumed was the case way back, that the adaptive potential was already present in the population and merely selected out in the presence of the antibiotic. Its already being there fits MY model. YOU have to show that it APPEARED in response to the antibiotic or you have not proved anything about mutations having anything to do with it. But the odds against a mutation happening along EVER that can protect against a completely unpredictable environmental change is just beyond calculation in the real world. Yes, it has to be common among his ancestors, most of whom are back in the first population that the new population split from if we're talking about a new ring species population for instance, and where this trait of his ancestors may have occurred at a relatively low frequency or been recessive or that sort of thing. But we are talking about population level changes. Again, the role you claim that mutations play in the whole process of evolution of all species is not going to be proved by your ability to create a culture of mutated bacteria. And if what you said above is the case, that the different bacteria were already in the population, then scrap the whole show because that fits MY model. *I* have no problem keeping this in mind. It's the tragic consequence of the Fall. And what I've been arguing is that it is very likely to occur at the far edge of the evolutionary processes, at the extremity of allele depletion, because it is this depletion which is the overall trend of all these processes, and ultimately powers the formation of new phenotypes to the point of speciation. Allelically depleted species simply do not have the capacity to produce an adaptive variety. So in my model extinction is the natural ultimate end of all the evolutionary processes. Were it not for the Fall, even the most extremely allelically-depleted species would exist without threat of extinction. My point exactly. Well, that's the evolutionary model for sure. In my model those that didn't die waiting, didn't die because those normal adaptive variations that had been provided them back at the Creation, happened to be still available to them despite horrific losses over the millennia. Not mutation, original creation. More like .0000000000000000001 likely. But anyway, how can you expect mutation to be anywhere near the kind of influence you are all claiming given its rarity, its high proportion of uselessness which may in fact be destructive in the end, and so on? Oh I'm not thinking of myself, just the plight of the creation. I expect all the death and ultimate exinction. It fits my model. But you guys are pursuing this fantasy of its all being normal, and that's far scarier than facing the facts of what is really happening. It isn't enough to do what you all claim it must do. It just isn't. Astronomically far from it. Here comes the Credo, the Statement of Faith. I guess you believe that. But that's only for one trait that has one gene for it, and there can be many genes for the same trait in some cases. Depends on how big the original genome was.Also could be that this mutation EZ was hypothesizing about, that simply reproduces a known allele where one has been lost, is simply part of the normal way DNA works. But then I do have to wonder why the cheetah hasn't experienced this. Faith, Crash, nothing but blind faith.

In saying it is driven by environment you seem to be claiming that natural selection is the only method that can bring about speciation? But a bottleneck can bring it about, and that can be caused by accidental factors that happen to isolate a tiny remnant of a population. Gene drift can bring it about. And migration alone can bring it about. There need be no selection pressures involved at all. Ring species may form simply by migration and isolation of a part of a population.These are all the processes that create new phenotypes, and you get speciation at a certain extremity of phenotype change. There is no reason to assume that the alleles that bring about these changes were not always present in all previous populations. There is no reason to assume mutation at any point and there is no reason to assume selection pressure, although selection pressure MAY certainly be part of it. This has been my argument from the very beginning. {EDIT: But I only recently started using "diversity" at the level of the phenotype by mistake. This confuses things. I merely mean that new phenotypes are brought about by the shuffling of alleles which may include loss of alleles}.In fact I used to overemphasize it to the slighting of the role of frequency changes without loss of alleles. It's simply a more extreme version of frequency changes, though: instead of one allele's becoming very rare in the new population it simply is nonexistent, because the individuals that possess it didn't happen to be in the migrating population at all. In the original population they might have been fairly numerous, but are simply not part of the new one at all.The cheetah, again, is an example of a population that has lost all but one of the alleles for many genes, in this case because of a bottleneck. But a series of population splits by migration can over time also eliminate alleles completely. Obviously this must be a common occurrence given that population splits in the wild are common. Paint doesn't make a useful analogy here. The removal of alleles allows others previously less frequent in the population, perhaps suppressed by being recessive, to be expressed and come to characterize the new population that is without the competing alleles. Usually it's a matter of change in frequencies and the previously dominant alleles are not completely eliminated but merely now far less frequent; but total loss can occur and in fact is pretty much guaranteed to occur over many population splits. In some domestic breeds you can be sure that you will NEVER get certain traits if you keep inbreeding them. They simply do not have the alleles for those traits any more. This is the problem with allowing the term "diversity" into this discussion. I finally allowed it, but I didn't like it at first at all. EZ brought it in and I didn't do a very good job of dealing with it at that point. I had been only saying that "phenotypic change" or "new phenotypes" is brought about by a reduction in allelic diversity, NOT "phenotypic diversity." Perhaps I should go back to that after all. I decided at one point that diversity might not be as big a problem as I'd thought, since what happens when frequencies change is that a bunch of new traits come out, and that IS diversity, and it IS caused by the increase in some alleles along with decrease in others; and if some alleles are totally lost, the new traits based on the remaining alleles that now come to the fore, that were previously less frequent in the population, STILL amount to an increase in diversity -- of traits, of phenotypes. This is all in the context of population splits.It's not a larger RANGE, it's simply the greater expression of previously unexpressed traits, or previously less frequently expressed traits.This is a semantic problem. I may have to throw out "diversity of phenotypes" after all. It just makes it more confusing as I feared. Get back to "new phenotypes" and "phenotypic change." OK, let me go back to my original way of saying it: Yes, and again I decided to change the terminology, thinking "allelic" might be clearer than "genetic" since EZ for one seemed to be getting confused by it. Fewer choices of alleles means that the fewer now bring about new traits that were not in the former population, at least not in such numbers. There is less competition from the lost or reduced alleles so that the greater frequency of the others comes to characterize the new population overall. This is a new phenotype brought about by the favoring of a smaller set of alleles than formerly existed.{EDIT: If a new population has fewer of some alleles than were present in the former population, then they will come to expression in greater numbers than they did in teh former population. So they are fewer with respect to the former population but greater in the new. These formerly few now get to proliferate and come to characterize the new population.It's sort of like, to ridiculously oversimply, say the former population had equal numbers of alleles for purple fur, green fur, orange fur and silver fur. Forget dominant-recessive and other sensible considerations. Say a portion of the population gets isolated, which is made up of 50% individuals with the purple allele, 30% with the green, 19% with the orange and 1% with the silver.Then say this population further splits and the new isolated population is made up of 40% individuals with the purple, 10% with the green, 30% with the orange and 20% with the silver.Say it further splits and this time only orange and silver migrate, with maybe one purple individual, no greens.And so on. I'm too tired to work out the implications. Maybe later. Exactly. But in this case I mean mostly different from the main type in the previous population. I'm sorry I gave into the pressure to use "diversity." I think there IS a new diversity of traits in a split-off population, certainly in the first generation or so, but what I'm really trying to say is merely that you get a new phenotype that characterizes that new population over time. Yes, but I'm talking about the point at which this population split off from the previous population. This new allelically depleted creature is a new phenotype in contrast to the old. But the usual example is when there are still plenty of alleles, only fewer than before the split. Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

NO, I am not thinking about this in an individual, but in the population.Drat, this is now awfully frustrating. My own fault for allowing that misuse of "diversity" to get into this and now the whole thing is a terminological nightmare. I knew better at first and then allowed it against my better judgment. Communication about these things is difficult at best; now it just seems impossible. Anyway.I can't take the time to get into this again for a while, but I'll just answer one small part of this one post: Again, SO sorry I allowed "diversity" into the description of the phenotype. Stupid of me. Please let's try to eliminate the idea of phenotypic/genotypic or organismal diversity or "diversity at the population level" from the discussion. I guess I need to go back through all my posts and edit them all to reject this word. Sigh.Anyway, about the cheetah: Again, forget "phenotypic diversity." The cheetah is a NEW phenotype, that's all I ever wanted to say, I'm only talking about new phenotypes coming about through these processes of evolution, particularly through the reduction of genetic diversity, a change in phenotype from an earlier type, in the cheetah's case brought about from the old through a bottleneck which severely reduced its alleles for certain loci. The lost alleles could no longer affect the phenotype. The phenotype is now completely defined for those particular traits by those single alleles. It is a NEW phenotype compared to the population it was bottlenecked from, differentiated from its parent population back who-knows-when by the dominance of these particular traits and by the loss of those traits it no longer shares with it.There are some cases where new phenotypes emerge in a population without any increase or decrease in alleles / genetic diversity, such as gene drift, such as population splits where all alleles are retained in both populations but only the frequencies change, etc. Some have said that speciation can occur this way. Point here is that INCREASE in genetic diversity is not needed to bring about new phenotypes/genotypes/organismal or population-level changes.There is only one situation in which an increase in genetic diversity occurs, and that is hybridization, a reintroduction of alleles where they had once been lost. Nothing new is added but old alleles are recombined. Does hybridization lead to new species?Or mutation, but that's a big questionmark still.But loss of alleles is still the general trend over time, and new phenotypes are certainly produced by this loss, and speciation as well. Instead of a mere reduction in frequency that allows other formerly suppressed alleles to be expressed in new traits in the new population, a complete absence of the competing alleles may be the case. Many population splits, say in a ring species, is very likely to bring about this situation, and speciation can certainly result from it.My claim is that this trend to loss of alleles is general for all species over time, and it comes about in the production of new phenotypes and new species, which requires that some alleles not be expressed while others are, and if the competing alleles are completely gone so much more certainly will the new phenotype come to dominate.
Edited by Faith, : No reason given.