More Evidence of Evolution - Geomyidae and Geomydoecus

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From this almost infinite all possible mutations (1 mutation of nucleotide in given sequence, two mutation or 10 mutations but on different places etc...) only one was picked by natural selection.

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Yeah, of course. Natural selection can only act on a mutation that has actually occurred. If a mutation does not occur, then there is nothing actually in existence upon which natural selection can act. Natural selection cannot act on potential mutations.

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Actually, if their god makes better pancakes, I'm totally switching sides. -- Charley the Australopithecine

You're getting way off-topic. This isn't a paper about mutations; this is a paper about parallel speciation, which, again, happened because of constraints on the population structure of both organisms. This has no meaning. Natural selection doesn't select mutations, it selects individuals, all of which have mutations. Some of those mutations produce a survival benefit, and they are preserved in the population. Some of those mutations produce a survival cost, and they will probably be selected against. Most of these mutations have no effect at all and they spread throughout the population stochastically, through genetic drift.Your 100:1 example is make-believe. This is not what speciation, or cospeciation, does. What we're talking about is population structure and phylogenic history, not mutations and genes. There's only one gene relevant to this example, and that's the gene they used to develop the molecular phylogenies in both groups of organisms - cytochrome oxidase I, a mitochondrial gene regularly used for this purpose because it's highly conserved. And I'm telling you that this example disproves directed evolution, because there's no coherent reason that pocket gophers and their pubic lice would be directed to speciate at exactly the same time, repeatedly.Rather, this example proves that evolution is not directed, but rather, occurs in response to environment - not from a prior program inserted by intelligence. Lice and gophers are so radically different that it's impossible to believe that they were directed to speciate in the same way, with radically divergent genomes.The parallel speciation phenomenon, in this case, proves that evolution here was not directed, but rather, occurred as a response to environment - the Darwinian explanation. You've completely misunderstood the article if you're under the impression that where it says "pure chance", it's referring to random mutations.This is not the case. "Pure chance" in this context simply means the chance of developing a convergent phylogeny between two populations that were, say, picked out of a hat. It has nothing to do with mutations in this context, and your arguments are all but nonsensical. (And again, I beg you to do a better job of rendering them readable in English.)Edited by crashfrog, : No reason given.

I'm not sure that you could be accurately characterized as the epitome of meekness. You're pretty aggressive for someone who still misunderstands the P<.01 part, and it's causing you to misinterpret all the rest: The P<.01, which is where I presume your 100:1 ratio comes from, applies to the statistical possibility that the findings of the researchers were due to chance. It does not apply to the possibility that a mutation will be selected. The paper doesn't mention such things, doesn't even speculate about them. The word "mutation" doesn't even appear in the paper.Let's say I was doing a study on a cancer treatment, and I discovered that the treatment on average reduced mortality in the year following initial diagnosis with a P<.01 probability of being due to chance. That doesn't mean the cancer patients had a 100:1 chance of survival. The P<.01 doesn't apply to the cancer patients at all. It applies to the probability that the study's results are due to chance. In other words, it's the probability that the study's results are incorrect.Anyway, I again suggest you read the paper: But let's examine part of your concluding comments: This observation is incorrect for two reasons. First, as already explained, the P<.01 is not the probability of a random mutation being selected by natural selection. It's the probability of the statistical results of the study being due to chance.Second, and more importantly, calculating the probability that a random mutation would be selected would be meaningless for the type of information this study was focused on, and nothing in the study would enable you to reach conclusions of this nature. But I understand the conclusion you're trying to reach, and it's clear you're thinking about the interplay of mutation and natural selection in the wrong way.Mutations occur all the time, but mutations in any species that is already well adapted for it's environment are likely to be selected against by natural selection. For example, if a rabbit is already well adapted for an annual average temperature of 60^oF, then any mutation that makes it better adapted for 55^oF or 65^oF would be selected against. It is only when the environment changes that mutations affecting temperature adaptation can be selected for and become fixed in the population so that a later generation of scientists can discover it in the DNA.This is why I mentioned that the mole forms the environment for the lice, and changes in mole morphology represent a change in lice environment. This places environmental pressure upon the lice, and now the constantly occurring mutations have a better chance of making the lice better instead of worse adapted, and so have a better chance of being selected instead of rejected. And so the mole and the lice speciate in concert with one another, and the evidence for these speciation events is recorded in their DNA, which is what the scientists who wrote this paper studied.Interestingly, your own idea of directed evolution is also consistent with this evidence (indeed, it would be consistent with any evidence, which is one of its problems), but speciation is taking place today, both artificially in the lab and naturally in the wild, and no designer/builder has even been detected tinkering with either mutation or selection.--Percy

Is it? If organisms speciated according to a built-in program of direction, wouldn't the gophers and the lice have speciated independantly, regardless of their ecological relationship? Doesn't the fact that one species is constrained to speciate parallel to the other prove that organisms speciate as a result of the effect of environment on population structure, and not according to some built-in plan?It strains credibility to suggest that a pubic lice and a pocket gopher, being so different from each other, would be programmed to speciate on coincidentally the same schedule. (In fact the paper explains what the chance of that happening is - less than .01. ) And we don't see the same phenomenon in most parasite/host relationships, which would seem to buttress the proof against directed evolution.Unless, I guess, MartinV wants to come out and say that they were directed to cospeciate to fool us into believing in evolution, which I guess I can't disprove. Maybe that's what you were referring to. Certainly if someone wanted to specify an "Intelligent Director" who wanted to make it look like evolution, they would need to provide evidence from a source aside from the natural world.

A beneficent designer would of course evolve his creations as necessary. The limited mobility of this type of lice made it necessary for the designer to evolve the lice whenever he evolved the moles.Being consistent with the evidence isn't an argument in favor of directed evolution. This is the problem with all proposals of godlike designer/builders, where whatever the evidence shows happened, that's what the designer/builder did, so they're not testable. Even worse, there's no positive evidence for any designer/builder.--Percy

Could the word “random” have a psychoactive effect on MartinV and his ilk? Something like "heathen" or "godless"? He might read “random” as “not by the hand of God,” which of course offends his faith. Everything said afterward about Darwinism is essentially blocked out by this attitude.But whose fault is it? I think MartinV and his ilk are understandably confused by the confusion amongst evolutionary biologists about the role of random mutations as they relate to natural selection. Here’s one measure of importance attached to mutation: What is confusing here is the implication that natural selection always requires random mutations to enable an evolutionary event. This explanation ignores the role of exaptation”alleles and genes already carried in the genome, remaining unexpressed until favorable changes of circumstances allow for their selection. Gould, for example, reasoned that the genetic potentials for exaptation may actually account more for the evolution of certain species than random mutations.So the notion of potential takes on new meaning. And those exapted genes and/or alleles do not have to come only from mutations”some find their way into a genome by way of horizontal DNA transfer, also viewed as gene flow.Maybe MartinV might be more comfortable with Darwinism his he saw that genetic potentials were often causal in the course of evolution. Then he could always say: Hey, look, if there are potentials then they can be seen as evidence of ”the hand of God.’”HM

Yeah, but why were they already carried there? Random mutation, most of the time. HGT is a form of gene flow, sure. But where did those genes come from to be HGT'd? Random mutation.All I'm saying is, it gets back to random mutation, eventually. The processes you're talking about explain how a given individual might come to possess a certain sequence, but the origin of that sequence is almost always random mutation.

Tsetse flies, maybe? Do you consider HGT a form of mutation?

Besides what crashfrog wrote, I would add the question why aren't these alleles expressed? Because the regulatory mechanisms don't transcribe them. Why would they become expressed? Because a mutation, presumably random, changes the regulatory parts of the genome to cause these alleles to be transcribed.

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Actually, if their god makes better pancakes, I'm totally switching sides. -- Charley the Australopithecine

Why, Hoot Man, you're not trying to substitute glib comebacks for intelligent debate, are you? Who on Earth would ever suspect you of acting so out-of-character? You seem to have missed my point completely. Sure, there are mechanisms that move genetic sequences from individual A to individual B that have nothing to do with mutation. (Obviously reproduction is such a process, but so is HGT, or retroviral insertion, or genetic engineering by dudes in labcoats, or what have you.)But how did it get to A in the first place? You can say "HGT" again, but then it's just a process of recursion. We follow the HGT's back to the individual who first had the genetic sequence without getting it via HGT or any other such process. That individual developed the sequence by random mutation.Processes like HGT move genetic sequences. Random mutation creates genetic sequences.

I'm actually replying to both Chiroptera and Crashfrog, not just Crashfrog.I think Hoot Mon raises a good point. A good sized segment of those on the science side believes the issue is one of education, that if only people were more informed they'd be more accepting of evolution. For those of us who accept this perspective (one I'm growing less and less receptive to), Hoot Mon is arguing that we're not doing as good a job as we could of educating MartinV.But the larger issue that this brings to mind is that the education approach is not an easy one. All creationist miseducators have to do is portray their fallacies in any number of convenient and easily understood ways and the evolutionists have a multi-day re-education task on their hands, one that most creationists won't stick around for, or that discussion won't stay civil long enough for.Attempting the educational approach is worthwhile because at a minimum it makes clear to those newly arrived at the issue that there are sound evidence-based reasons for accepting evolution. But while there will be conversions in both directions, the vast majority of people who care are already entrenched in their positions, evolutionists because of evidence from the natural world, fundamentalists because of revelation from God in the Bible.So when fundamentalists attempt to influence boards of education to select certain textbooks or change the science curriculum, while attempts to educate such boards is still a good idea, there are other options more likely to have a positive effect. These options do not address the hope of reconciliation between the two sides, but they do allow science education to kept free of religious influences. Such approaches tend to ignore the specific scientific issues and stress public relations approaches that characterize the fundamentalists as special interest groups, emphasize the economic risks to a region perceived as anti-science, and highlight the negative effect on the opportunities for higher education for students from such regions applying to universities.--Percy

Well, they might already be expressed when exaptation takes place. Let me try this hypothetical scenario:There are two alleles that express the inner ligament protein of the human thumb. One is a dominant allele, which is not as flexible as the other allele and prevents the thumb from curving backwards into a “hitchhiker” position. The other allele, the recessive one, produces a more flexible ligament, permitting the thumb to curve backwards into the so-called “hitchhiker’s thumb” position.Right now, neither allele plays any role in selection, so far as we know; the gene is evolutionarily neutral. But let’s say something changes, something that would benefit the recessive hitchhiker’s thumb allele. Let’s say it assumes a sexual advantage”mate attraction, perhaps”so that those humans with hitchhiker thumbs are reproductively favored over those who don’t have them. Here would be a case of exaptation accounting for a selection advantage without the need for mutation.”HM

What you've described isn't exaptation, it's just selection.You say "without the need for mutation", but mutation isn't a part of selection; so naturally you don't see mutation in the parts that are just selection. Mutation comes in the part you've ignored - where the multiple alleles for this protein came from.The mutation is that, where there was one allele for the ligament protein, there are now two. Selection is when, later, individuals with one of those alleles reproduce more than individuals with the other one.How you misinterpreted that as a situation of exaptation, where the function of a biological characteristic becomes something other than what it had been as it evolved, is beyond me, but it only serves to illustrate another instance where you've displayed absolute confidence in your completely erroneous understanding of basic biology.

And why we are sure that such cospeciation needs darwinistic explanation - chance 1:100 by "pure chance" considering millions of years of evolution is more than probable to occurs. Such high probability of "pure chance" can explain cospeciation as well - even without "natural selection" that "picked out of hat" morphology made by "random mutation". Such high probability means that cospeciation would occurs whatever happens. Such high probability means that cospeciation is inevitable. That cospeciation is governed by inevitability, by probability = 1. By Nomogenesis.

I actually thought Hoot Mon's example was okay. Exaptation happens when a feature becomes used for a purpose other than the one for which it evolved. In Hoot Mon's example the hitchhiker's thumb did not play a role in sexual selection, and then it did. It didn't evolve for the purpose of sexual selection, so this *is* an example of exaptation. His example has to be somewhat qualified since something else evolved (sexual selection) to change the hitchhiker's thumb's purpose, which is why it isn't a perfect example.But even if I'm wrong and Hoot Mon's example is full of holes, the point he was trying to make still holds, that a mutation might already be expressed before something else changes to make it vulnerable to selection pressures.But even though Hoot Mon's point is valid, it's a minor quibble of a point. Chiroptera was only trying to explain a principle in a general sort of way, not enumerate all the possible circumstances and permutations.--Percy