A barrier to macroevolution & objections to it

So far your arguments that mutation cannot keep pace with the loss of alleles have been:1) Just ignore mutation. No further comment on the rationality of this argument is required.2) A guess that the number of alleles lost (which will be almost entirely neutral and detrimental alleles) with a guess at the number of beneficial mutations. The guessing alone would disqualify this as a logical argument - but the fact that the numbers are not equivalent completely invalidates it. To that should be added the difficulty in conclusively identifying mutations and the fact that you were reluctant to accept even an example where there was good eveidence that the new allele was a mutation (one that seems to be evolutionarily neutral, but beneficial in other terms). Thius it must be said that your guess at the number of beneficial mutations is likely to be an underestimate.So your asssertion is not the conclusion of a "logical argument". It is an opinion and the so-called "logical arguments" are fallacious post hoc attempts to support that opinion.Edited by PaulK, : No reason given.

Yes, ignoring mutation.http://EvC Forum: What is the mechanism that prevents microevolution to become macroevolution? -->EvC Forum: What is the mechanism that prevents microevolution to become macroevolution? So Faith claims that it is a "fact" that mutation "simply doesn't" "take up the slack". She says that has a "logical argument" to that effect. But we have to "keep mutation out of the picture" i.e. ignore it...But to be fair Faith has since moved to ignoring neutral mutations (i.e. the majority). Her argument is based on guessing the number of beneficial mutations - which, of course, is the wrong number when looking at allele diversity.Edited by PaulK, : No reason given.

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Evidence that mutation increases alleles after speciation has been promised but not delivered, and that is where the ball remains until it is delivered

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What is there about speciation that would STOP mutation from producing new alleles ?

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Yes, I see your point. But Faith is merely trying to establish the first point which is that normal speciation events result in stasis or loss of genetic information. Since the veracity of this concept is denied by most here, it is hardly possible to proceed to the second question - namely whether mutation is a sufficient mechanism to overcome the prior loss.

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If that is the case - and in fact I think you have things reversed - then Faith needs to stop claiming that mutation cannot produce sufficient new alleles to replace those lost until she has established her other claim. Yet she calls it a fact, and keeps claiming to have a logical argument for it when neither appears to be the case.Personally I am of the opinion that speciation usually requires mutation to produce divergence between the split population. And I have seen no argument to the contrary from Faith or any reason to suppose it is not true.I would add that the creationist "dividing line" you refer to seems to be entirely artificial and based on the assumption that evolution must be false.Certainly the claim that mutation cannot produce "new information" is never supported by sound argument and is usually not even accompanied with a measure of information that could be investigated. Spetner is I think the only person who has made a half-serious attempt and even he doesn't stick with a consistent measure of information - instead it seems that changes his measure as needed to get the results he wants.

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It has to produce useful alleles

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Alleles that work as well as those already in the population are "useful".

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It has to produce more useful alleles than deleterious or useless alleles. Evolution can't possibly have been built on a trade-off between disease and health.

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No, it doesn't. You need to take into account the role of selection. It's enough that it produces some new alleles that will be beneficial in the future in some species (evolution only has to account for what does happen - and many species go extinct without leaving descendants).

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It has to produce enough of them to take a new species from a state of sometimes severe genetic depletion to genetic abundance, where its parent species started many selections behind it.

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There's no reason to assume that new species typically start off in a state of "severe genetic depletion". There may be some reduction in diversity but it is unlikely to be sufficient to be an immediate threat to survival.

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The development of a new species, after all, is the point at which evolution is supposed to turn to macroevolution, so if in fact the new species has a lot fewer alleles per gene than other populations from which it speciated, mutation has to restore all that, and that would only get it back to where the original population is. So it has to provide a lot more than that.

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This really makes no sense. THe appearance of a new species is part of the DEFINITION of macroevolution used by biologists. It does not require that the new species have many fewer alleles per gene than the parent species nor for it to develop many more alleles per gene.

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And this is a very odd situation, since speciation itself is supposed to be this launching point for macroevolution. Why then are we having to add anything in at this point, a whole bunch of mutations to make up for the loss of genetic diversity, and note well, the very loss of diversity that makes the speciation happen in the first place. There is something wrong with this picture.

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Yes, there is something very wrong with your picture. You fail to understnad the definition of "macroevolution" used, you assume a radical depletion that is not required and you assume a drastic increase far beyond what is required.

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My first point is that whether or not creationists have identified the proper criteria, the evolutionist can not assume that none exists.

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The fact that no boundary has been identified, plus the evidence for common descent is adequate reason to provisionally assume that there is no such boundary.

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For example, the drosophilia eye and the human eye are composed of very different genetic makeups. Can mutations lead from one to the other? It has never been shown to occur.

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The path between the two may indeed be very unlikely. However since nobody proposes that evolution did follow that path it hardly represents a problem for evolution.

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That is a serious missing link in the mutational change, without which, darwinian evolution can not be understood to have occured.

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But it isn't a "missing link" because no such link is thought to exist. Evolutionary theory in the broad sense says that humans and drosophilia had a common ancestor - and the hox genes are evidence of that. But it does not say that that ancestor had a compound eye.

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This does seem to be what people assume, and it may account for most of the confusion. Why it is assumed is a question. Is it only because it is vaguely recognized that speciation otherwise does often/usually/always deplete genetic diversity?

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I fact I gave a reason. Incompatibility is more likely to arise after the population splits because it would be detrimental before the population split.

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But breeders have always selected from traits already present, not traits that just appeared for the purpose of choosing them.

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They CAN'T select traits that don't exist. But if a trait does appear (like the "scottish fold" cat) they can and sometimes do select it.

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You can't just assume their origin was mutation once upon a time

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And you can't just assume that it wasn't - but you do.

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Natural selection selects traits already present, of course. Except for this one bacteria experiment that appears to show mutation out of the blue of a useful new trait...

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Several experiemnts - including replications - in fact. And even one experiment is more than you've produced.

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There is no reason to think that the observed changes in phenotype as a result of population split have any other basis than the expression of already- present alleles that are no longer in competition with others from the previous population.

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There's even less reason to suppose that is all that it is. So where's YOUR evidence ?

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The fact the drophilia and humans do not share a direct lineage is irrelevant, because the point in question is whether mutations CAN account for the transition of one species organ into another - not whether historically they did.

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On the contrary it IS relevant because given the fact that we have seperate and divergent lineages, there may very well be no viable evolutionary route between them. And given the timescales involved it certainly can't be claimed that it would be a sensible laboratory experiment.

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So I suppose you'd claim that any two species which possess cleary distinct organs (with the same function) belong to separate and divergent lineages thus being non-subjectable to experimentation because they lack viable evolutionary routes between them.

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If the organs are so clearly distinct then that is highly likely. However I did not base my claims on that, but on knowledge of the proposed phyologeny of drosphilia and of humans. i.e. what the relevant part of evolutionary theory actually says.

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And Evolution is falsifiable?

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The fact that your proposed argument is invalid because it is based on ignorance of what evolutionary theory actually proposes is hardly a good argument that evolution is unfalsifiable.

I'm not a biologist, just an interested layman. So far as I am aware there is no requirement in evolutionary theory that "clearly distinct" organs performing the same role must be related so that one directly evolved from the other. In fact the more clearly distinct they are the less closely related we would expect them to be, and since evolution can't be assumed to "stay still" in either lineage divergence is expected.

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If not, your theory is unfalsifiable.

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Unfalsifiability requires that there is no concievable evidence that could cause us to reject evolution. It does not require that results that we would expect if a theory were true should be treated as falsifications !

Let me put it this way. Would you say that creationism is falsified as scence because we can't get God to create a new species or "kind" for us in the lab, on cue ? Or is it an unreasonable test that doesn't allow us to draw that conclusion ?

I'm not going to go off my planned line of argument.So you agree that the test is unreasonable. Does the fact that that test is unreasonable allow me to conclude that creationism is unfalsifiable ?

The test is the one I stated. To get God to create a new "kind" in the laboratory, reliably and repeatably (you know that's a requirement for experiments, right ?). We agree that this is not a reasonable test.So I repeat the question. Does the fact that the test is unreasonable allow us to conclude that creationism is unfalsifiable ?

Genetic Surprise: Mobile Genes Found To Pressure Species FormationThis is an important bit - it confirms what I've been saying. No mention of incompatible alleles causing speciation anywhere. Presumably you could get similar effects with incompatible alleles. But I'm not aware of any such case, and I think that it would be more difficult so we certainly can't say that it is the usual situation. - not when there are known alternativesEdited by PaulK, : No reason given.

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This thread is about a barrier to macroevolution, for which I've produced scientific facts and reasoned argument therefrom.

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No, you have failed to producer any valid support for your assertion. It remains your unsupported opinion, and hacve produced absolutely no reason to beleive that it is true.