A barrier to macroevolution & objections to it

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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.

My first point is that whether or not creationists have identified the proper criteria, the evolutionist can not assume that none exists.My second point is to establish at least one criteria that evolution has not been observed to account for. Organs and by implication the genes behind the organs. 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. As I pointed out, many scientists are hopeful that Hox genes will provide such evidence. I believe it is largely based on Hox genes that Biochemist Michael Denton recanted his anti-evolutionist stance. I am skeptical that Hox genes will play the savior to the mutational mechanism, but we'll see. To date, however, optimism is the only support the mutational mechanism has as to accounting for the transition of one type of gene into another.That is a serious missing link in the mutational change, without which, darwinian evolution
can not be understood to have occured.

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?But breeders have always selected from traits already present, not traits that just appeared for the purpose of choosing them. You can't just assume their origin was mutation once upon a time. 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, and that's the ONLY experiment that has shown such a thing, in a one-celled animal, really not a basis for assuming that as a normal occurrence in complex organisms. 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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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.

This is a somewhat simplistic way of looking at it. New organs don't just don't appear. We're talking about the accumulation of mutations over three billion years, not spontanious organ generation. They deserve to be be ignored - they are straw-man issues of your own creation.- As far as I'm concerned most mammals, for example, have a strikingly similar body plan. Four limbs, one head, a tail, heart, ribcage etc. The simlarities far outweigh the differences.- "Increased complexity" isn't a problem. Ever seen a picture of a magnified snowflake? This sounds like a warmed over version of YEC thermodynamics nonsense. The Earth is not a closed system.Edited by RickJB, : No reason given.

I used the example of the drosophilia eye vs the human eye:A. to contrast organs that would be accepted as being different.B. because to date, little to no contrastive studies have been done comparing closer relations - say chimps and humans. Keep in mind the state of genetics; We have only recently finished cataloguing the human genome. We have mapped the genomes of certain other species but the VAST majority of species' genomes are so far unmapped, and information on the genomes of those species that have been mapped is not readily available...When such comparative studies are available, studying the transition of oranismal genetics will be possible. For now, we have to make to with what we have available.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. This is a laboratory-testable proposition. To date, it has not happend.

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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 ?

In fact, that's not how I am looking at it. I don't feel like restating myself everytime I'm misrepresented, so I may not continue to respond since I'd just be repeating myself unnecessarily.I never mentioned spontaneous organ generation. I merely asked whether mutations are capable of novel organ generation - obviously over 3 billion years according to ToE. The question is not the time, it's the mechanism. Is it up to the task?

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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.

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.And Evolution is falsifiable?

This is one serious misunderstanding. It doesn't.The filter of selection simply has to leave more useful ones than deleterious.Apparently, about half of human pregnancies end quickly in a spontaneious abortion. Perhaps that is a filter that removes a lot of the most deleterious mutations.Also you've forgotten that "useless" isn't a term you can safely apply to diversity. You arguement has been that genetic diversity HAS to decrease. "Useless" mutations are a counter to that.

Here's a nice vid showing some of the current thinking about eye formation. Interesting even if there is still much more for us to learn.Evolution: Library: Evolution of the EyeThe scientific consensus is that mutations are certainly up to the task of organ generation. Furthermore, no barrier to this process has been seen to exist.

This is an oft repeated concept that needs to be understood. Before something has to be denied, the affirmative must be established.You can tell me, for example, that you've created gold from straw. Would I stop what I'm doing and go prove the opposite? Of course not; I'd keep doing what I'm doing because in the absence of any proof from you, it's just a say so story.The assertation has been made that novel organs can and are generated by mutational mechanisms. If you're wondering where this assertation has been made, it is inherent in the darwinian understanding of mutations accounting for all of life's diversity. (This is an example of how darwinianism fails to properly understand the scope of its claims). Until this asseration has been heavily supported, it would be ridiculous to establish a barrier to this proccess - there is no 'proccess' for which a barrier is required...As to the vid I'll take a lookEdited by mjfloresta, : Orthography

Being that human eyes and compond eyes did not evolve from eachother your question is fatally misplaced. You will never find a string of mutations that have a human eye "lead" to a compound eye. The mutations the created the various eyes are changes from a more primitive eye that is very similar to the current one. This will seperate for each type of eye that you discussed. If they could show it to occur, this would completely invalidate the ToE. I hope you undersand this and that by such statements you are operating with a vastly uninformed knowledge of the ToE.

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Of course, biblical creationists are committed to belief in God's written Word, the Bible, which forbids bearing false witness; --AIG (lest they forget)