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Author Topic:   A Creationist's view of Natural Limitation to Evolutionary Processes (2/14/05)
Brad McFall
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Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 151 of 218 (341136)
08-18-2006 4:11 PM
Reply to: Message 149 by Equinox
08-18-2006 3:25 PM


Re: Considering rapid rate of mutation
Let’s say Faith intended “genetic” in the sense of Bateson as cited by Gould(orange below):
quote:
SJ GOULD "The Structure of Evolutionary Theory"
If she even unconsciously and materially had had a vibrationally envisoned reality of the transient transition from any genetic realism to a form phenotypically ontogenized then she could have used “variation” polyvocally without confounding it with the shape of any particular actual creature. She would have not provided the statistical evidence that such was the case but that it might be collected can not judged against a priori seems to me. Now if a responder to Faith insisted that Bateson was materially incorrect and by analogy of any dream Faith is 'incorrect' as Gould proposed etc., this would not work either, because for Gould to retain his position he needed to deny to D’Arcy Thompson direct imposition whether by a law of nature or the “hand” of God in the Cartesian place of transformed co-ordinates.
As long as there are to be provable limits to natural selection caused change by human artificial selection experiments (Provine denied these exist to Johnson but can one deny these to Faith?) it seems possible that evolution could slow down a posterori (although we do not know this as of yet) if Fisher’s theorem relating genetical variance to fitness was mediated by counter active niche construction (for as Kant said, the first condition he judged would be the habitat not the kind) (counter active construction works organically against already existing selection pressures (see book “NicheConstruction””) mediated by the 2nd law of thermo within macrothermodyanmics(Gladyshev). Thus Fisher’s thought that entropy and his law were analogous would cash out the academic tension supposed to result in nothing between Wright and Fisher into this "genetic variance" that is molecular, no matter what “phase” the history of this biology is incurred to.
Who is to say whether space or time is being represented here??? I think Gould went too far in relating Bateson and Galton but that is just my tail end of the argument. I think rather he failed so “save” the notion of meristic variation itself.

This message is a reply to:
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 Message 153 by Faith, posted 08-19-2006 2:17 AM Brad McFall has replied

Faith 
Suspended Member (Idle past 1521 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 152 of 218 (341139)
08-18-2006 4:11 PM
Reply to: Message 148 by ramoss
08-18-2006 2:20 PM


You are making a couple of mistakes in your reasoning. 1) most mutations are 'neutral' .
I took that into account in what I said. However, this is most likely not true if I understand the process, and I may not. I think all you mean is that they produce no clear change for positive or negative in the organism, but in the sense that they are a mistake in the production of an allele they are a destructive process, isn't this so? That is, they replace a functioning allele with something whose function is not clear if it has a function at all. Is this "neutral?" Perhaps I misunderstand this and if so, please explain.
2) Unless there is some survival reason for a genetic disease, it tends to become less over time. For example, the gene for diabeties. You would think that it would get less as generations went by, but they found that when one parent had that gene, and the other didn't, there was a bigger perceptange of children born with the gene than expected. Since most pregnancies end in miscarriage, the conclusion that can be drawn from this is that the gene that might cause health problems later in life gave a survival characteristic to a fetus in the womb. There were less spontanous miscarrages with fetus's that carried the gene than did not.
A very backhanded notion of "survival" I would say, that for some reason a genetic disorder that causes early death nevertheless is protected in the womb so that the person can be born and grow up and have children who also have the disorder and die young. Diabolical process this evolution.
You are also ignoring the filtering of natural selection. "bad" mutations are more likely to be 'filtered' out than neutral or "good" mutations.
Well, natural selection is one of those "evolutionary processes" I have been discussing all along that lead to decreased genetic variability. I would think that anything called an "evolutionary process" ahould lead to an increase in diversity, but this is not the case. I would point out again that you don't just select out one trait by natural selection, but many other alleles may be selected out in the very process of selecting out a disease or selecting in something else, quite randomly, which is this overall trend to genetic decrease I've been talking about. So, presumably, most diseased genes are eliminated in the selection process, but others die along with them. And along with the greater survivability of diabetics there is simply no formula for a healthy species let alone the strength, the variability, the many USEFUL genetic options one would expect to find if evolution were true, implied in any of this.
As for the 'things are getting worse' senerio from the creationsist... there is no objective evidence for it.
Well, it's fortunately a very slow trend, and the reason there is no evidence for it yet is that what evidence there is at the moment is co-opted by evolutionist explanations, bad fit though they are, as well as that the science of genetics is very new and what happened in the previous few millennia can only be guessed at.
Edited by Faith, : Various grammatical changes for clarity.

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 Message 148 by ramoss, posted 08-18-2006 2:20 PM ramoss has replied

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Faith 
Suspended Member (Idle past 1521 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 153 of 218 (341273)
08-19-2006 2:17 AM
Reply to: Message 151 by Brad McFall
08-18-2006 4:11 PM


Back to reduced genetic variability in speciation events
As long as there are to be provable limits to natural selection caused change by human artificial selection experiments (Provine denied these exist to Johnson but can one deny these to Faith?) it seems possible that evolution could slow down a posterori (although we do not know this as of yet)
I'm sorry, I have a terrible time understanding you, but you seem to be supporting my thoughts to some extent in the above? Somebody "denied" that there are provable limits to natural-selection-caused change by human artificial-selection experiments? Denied this to someone but can't deny it to me? I would think that would depend on the ability to demonstrate that these limits do not exist, wouldn't it? But don't breeders of all kinds have to deal with the practical ramifications of this very situation all the time? The more you select, the more you eliminate genetic options. That's the point, you WANT to eliminate genetic options -- this is the formula for producing a new phenotype.
And this reduction, if repeated over many generations until you have a phenotype completely maintained by inbreeding, this very process that produces the new type ALSO tends to multiply genetically caused health problems. Isn't it true that some "new species" in the wild, that is, "species" that are naturally rather than artificially selected, suffer from genetic problems of various sorts that make them vulnerable to extinction? Combining this vulnerability with the reduced genetic variability that reduces the possibility of further change, and with the inability to interbreed with the parent species from which it evolved, which is one of the hallmarks of "speciation," overall the processes of speciation are not beneficial to any creature. The overall tendency, slow but sure over many generations, noticed most in the dramatic cases of severe selection pressures (as in domestic breeding for instance), is to new phenotypes at the expense of strength and health. Isn't this the case with the cheetah (an animal that does surprisingly well considering its genetic handicaps)?
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
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DrJones*
Member
Posts: 2293
From: Edmonton, Alberta, Canada
Joined: 08-19-2004
Member Rating: 5.9


Message 154 of 218 (341279)
08-19-2006 2:36 AM
Reply to: Message 152 by Faith
08-18-2006 4:11 PM


Is this "neutral?" Perhaps I misunderstand this and if so, please explain.
Good, bad and neutral are in relation to if the mutation helps or hurts the organism to reproduce. I have a condition called keratoconus, which has a genetic component. My corneas become deformed and don't focus light correctly and in the long run without cornea transplants I'd be blind. Keratoconus does not strike until late puberty and has a slow progression therefore it would not be a hinderance to reproduction. This is an example of a neutral mutation.

Just a monkey in a long line of kings.
If "elitist" just means "not the dumbest motherfucker in the room", I'll be an elitist!
*not an actual doctor

This message is a reply to:
 Message 152 by Faith, posted 08-18-2006 4:11 PM Faith has replied

Replies to this message:
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Faith 
Suspended Member (Idle past 1521 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 155 of 218 (341283)
08-19-2006 2:44 AM
Reply to: Message 154 by DrJones*
08-19-2006 2:36 AM


Thank you. This clearly demonstrates that the mutation is actually harmful to the organism, person, in this case you, although it is called neutral for the merely technical reason that it does not interfere with reproduction. It's the same situation as in the case of diabetes, which causes all kinds of misery and ultimately kills people, though it doesn't interfere with reproduction and so escapes the selection processes that would weed it out.
This is a very odd trend if you think about it. It would seem to lead to a proliferation of genetic diseases in the population to such an extent that over a few millennia there couldn't be a healthy species left on earth.
{Edit: Which is pretty much what biblical creationism says. Except that we assume that this is not the normal way genetics works. We assume PRIOR greater health, and gradual deterioration over time, due to the accumulating effects of the Fall from generation to generation. Only uniformitarianism supposes that such disease processes are normal, but logically this should have led to nothing but sickness and weakness in all species by now, and mass extinctions despite reproductive ability, if it really is a normal process of evolution}.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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DrJones*
Member
Posts: 2293
From: Edmonton, Alberta, Canada
Joined: 08-19-2004
Member Rating: 5.9


Message 156 of 218 (341288)
08-19-2006 2:51 AM
Reply to: Message 155 by Faith
08-19-2006 2:44 AM


This clearly demonstrates that the mutation is actually harmful to the organism, person, in this case you, although it is called neutral for the merely technical reason that it does not interfere with reproduction.
Calling it a "merely technical reason" is ignoring the point. Evolution does not care about the individual, it cares about reproduction. Once the individual's genes have been passed on it becomes irrelevant to evolution.
This is a very odd trend if you think about it. It would seem to lead to a proliferation of genetic diseases in the population to such an extent that over a few millennia there couldn't be a healthy species left on earth.
Sure bad (and in this case I mean bad to the individual in the long term, like my keratoconus) mutations can slip past the reproduction filter, but so do good and neutral mutations that can counter or modify those bad ones.
edited to address your edit
but logically this should have led to nothing but sickness and weakness in all species by now
Only if you ignore good and neutral mutations
Edited by DrJones*, : responding to faith's edit

Just a monkey in a long line of kings.
If "elitist" just means "not the dumbest motherfucker in the room", I'll be an elitist!
*not an actual doctor

This message is a reply to:
 Message 155 by Faith, posted 08-19-2006 2:44 AM Faith has replied

Replies to this message:
 Message 157 by Faith, posted 08-19-2006 3:02 AM DrJones* has replied

Faith 
Suspended Member (Idle past 1521 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 157 of 218 (341292)
08-19-2006 3:02 AM
Reply to: Message 156 by DrJones*
08-19-2006 2:51 AM


This clearly demonstrates that the mutation is actually harmful to the organism, person, in this case you, although it is called neutral for the merely technical reason that it does not interfere with reproduction.
Calling it a "merely technical reason" is ignoring the point. Evolution does not care about the individual, it cares about reproduction. Once the individual's genes have been passed on it becomes irrelevant to evolution.
Far from ignoring the point, this IS the point. Since the defective genes are passed on we have a state of increasing genetic disease in the population.
Once the individual's genes have been passed on it becomes irrelevant to evolution.
And what I am saying is that this means that evolution is really impossible, since not only does speciation lead to decreased genetic variability, but the passing on of diseases in the population leads to overall lack of vigor that all by itself tends to extinction rather than to anything that could produce a healthy species as evolution implies must happen.
This is a very odd trend if you think about it. It would seem to lead to a proliferation of genetic diseases in the population to such an extent that over a few millennia there couldn't be a healthy species left on earth.
Sure bad (and in this case I mean bad to the individual in the long term, like my keratoconus) mutations can slip past the reproduction filter, but so do good and neutral mutations that can counter or modify those bad ones.
So far in this discussion there have been no examples of these, only examples of "neutral" mutations that cause disease.
but logically this should have led to nothing but sickness and weakness in all species by now
Only if you ignore good and neutral mutations
I'm addressing a supposed "neutral" mutation, two of them, both causing disease. The supposed "good" mutations are pretty much a wishful fantasy so far.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
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Replies to this message:
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 Message 164 by Percy, posted 08-19-2006 11:10 AM Faith has replied
 Message 165 by nator, posted 08-19-2006 11:23 AM Faith has replied
 Message 166 by nator, posted 08-19-2006 11:41 AM Faith has replied

DrJones*
Member
Posts: 2293
From: Edmonton, Alberta, Canada
Joined: 08-19-2004
Member Rating: 5.9


Message 158 of 218 (341296)
08-19-2006 3:10 AM
Reply to: Message 157 by Faith
08-19-2006 3:02 AM


Far from ignoring the point, this IS the point. Since the defective genes are passed on we have a state of increasing genetic disease in the population.
A genetic disease in the population that has already reproduced is irrelevant. If I have a genetic disease that kills me 15 seconds after I reproduce am I evolutionary failure or success? Answer: success because I reproduced and passed on my genes.
o far there have been no examples of these, only examples of "neutral" mutations that cause disease
well I'm just a layperson you'll have to find someone more learned than I to show you those.
These supposed good mutations are pretty much a wishful fantasy so far.
There's good old sickle cell anemia, which helps the organism live to reproduce by giving them a resistance to malaria. I suspect you'll hand wave this away by claiming that since it hurts the organism in the long run that it is not "good", but in evolutionary (which is what we're talking about) terms it is.

Just a monkey in a long line of kings.
If "elitist" just means "not the dumbest motherfucker in the room", I'll be an elitist!
*not an actual doctor

This message is a reply to:
 Message 157 by Faith, posted 08-19-2006 3:02 AM Faith has replied

Replies to this message:
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Faith 
Suspended Member (Idle past 1521 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 159 of 218 (341303)
08-19-2006 3:27 AM
Reply to: Message 158 by DrJones*
08-19-2006 3:10 AM


Yes, as you say, and I agree and find it very telling, in evolutionary terms, genetic disease may be "good," even without a secondary benefit such as sickle cell anemia happens to confer. It is important to keep this in mind.

This message is a reply to:
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Brad McFall
Member (Idle past 5110 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 160 of 218 (341324)
08-19-2006 8:49 AM
Reply to: Message 153 by Faith
08-19-2006 2:17 AM


Re: Back to reduced genetic variability in speciation events
Yes I was generally supporting you position.
Chicken breeders who have been artifically selecting for more eggs have gotten chickens with better ability to lay more and more eggs.
Will Provine, who grew up on such a farm, and talks with the chickens' dept. at Cornell asserted to Phil Johnson in the mid 90s that there is no limit to this process because the chicks hatched continue to be more fecund. The only graph of this data I saw from Lerner in the 50s indicates that allthough there does appear to be continued improvement in egg productivity the gains made selectively per generation seem to be dropping off.
I think there IS some limit. I have thought up some theoretical means to this end. That is why I do not understand how posters can be objecting to your use of this idea unless like Will they wil it not to be the case but I did not read them asking you for information about the limit itself.

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Dr Adequate
Member (Idle past 361 days)
Posts: 16113
Joined: 07-20-2006


Message 161 of 218 (341333)
08-19-2006 10:02 AM
Reply to: Message 157 by Faith
08-19-2006 3:02 AM


Far from ignoring the point, this IS the point. Since the defective genes are passed on we have a state of increasing genetic disease in the population.
No. Natural selection favors good genes over bad ones.
And what I am saying is that this means that evolution is really impossible, since not only does speciation lead to decreased genetic variability...
Obviously, other things being equal, there is more genetic variability in two species than in one.
but the passing on of diseases in the population leads to overall lack of vigor that all by itself tends to extinction rather than to anything that could produce a healthy species as evolution implies must happen.
No: see my first comment. Such genes would not lead to the extinction of the species, but to the extinction of the group within that species carrying those genes, keeping that species healthy. One animal is not harmed by the bad genes of another.
This is a very odd trend if you think about it. It would seem to lead to a proliferation of genetic diseases in the population to such an extent that over a few millennia there couldn't be a healthy species left on earth.
And since even creationists admit to "a few millenia", it is clear that your reasoning must be wrong, since there are in fact no "unhealthy species", except for those which have had their gene pool dramatically bottlenecked by human activity --- the cheetah, for example.
The supposed "good" mutations are pretty much a wishful fantasy so far.
Take for example the evolution of antibiotic resistance in bacteria. This is scarcely "wishful fantasy", and it is certainly good for the bacteria.

This message is a reply to:
 Message 157 by Faith, posted 08-19-2006 3:02 AM Faith has not replied

ramoss
Member (Idle past 689 days)
Posts: 3228
Joined: 08-11-2004


Message 162 of 218 (341342)
08-19-2006 10:56 AM
Reply to: Message 152 by Faith
08-18-2006 4:11 PM


Well, since it is true, you do not understand the process. Most mutations do not produce either an advantage or disadvantage, it is for the most part, merely a change. Some of these genes don't provide an advantage or disadvanate in the current environment, but MIGHT, if the environment changes. If it is a 'change in alle', it might or might not be destructive. ALl it means is that the duplication process of the gene when the egg/sperm was created was imperfect. If it is not benefictial,the gene gets filtered out via natural selection. Many of these changes seem to stop the organism from forming in embryo form (did you know that 75% of all human pregnancies end in miscarrage , mostly during the first month?
As for the tend for things 'gettings worse'. I havent' seen ANY evidence for it being true at all. I have seen examples of beneficial mutations .. such as delta 26, and the HDL cholestrol gene of that sicilian family.

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nator
Member (Idle past 2247 days)
Posts: 12961
From: Ann Arbor
Joined: 12-09-2001


Message 163 of 218 (341346)
08-19-2006 11:10 AM
Reply to: Message 146 by Faith
08-18-2006 1:00 PM


quote:
The problem is that most changes by mistake are not desirable ones.
Most genetic changes by mistake are neutral with regards to fitness, actually.
quote:
"Genetic difference" in itself is not at all desirable in other words. This is how we get all the genetic diseases.
This is also how we get genetic benefits.
Bacteria obtain antibiotic resistance in exactly this way, which would certainly be a benefit to the bacteria, right?

"Science is like a blabbermouth who ruins a movie by telling you how it ends! Well I say there are some things we don't want to know! Important things!"
- Ned Flanders
"Question with boldness even the existence of God; because, if there be one, he must more approve of the homage of reason than that of blindfolded fear." - Thomas Jefferson

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Percy
Member
Posts: 22606
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.0


Message 164 of 218 (341349)
08-19-2006 11:10 AM
Reply to: Message 157 by Faith
08-19-2006 3:02 AM


Faith writes:
Far from ignoring the point, this IS the point. Since the defective genes are passed on we have a state of increasing genetic disease in the population.
Only if there's no selection is there a situation of increasing genetic defects in a population, which may be the precise case for homo sapiens. If that's your point, then I agree with you. One of the dangers the human race poses for its own survival is that our ability to develop medical treatments for genetic diseases allows people with genetic defects, who in earlier times would have died young, to produce offspring.
One extremem example that comes to mind is cystic fibrosis. Individuals with this genetic defect used to die young, but modern medicine now allows many to live into their 40's. Because cystic fibrosis is an extreme example where every victim is intimately familiar with the consequences of the disease, victims probably rarely pass this gene on. They either choose not to have children, or they use genetic screening to check for the presence of two defective copies of the CFTR gene before birth and terminate the pregnancy.
But other less severe genetic defects, like color blindness, are probably passed on all the time. In modern societies the survival cost of color blindness is minimal, but in prehistoric times it was probably much more important. For instance, those with color blindness often have much greater difficulty seeing in the dark.
Visual acuity and focussing ability also has a genetic component. Darwin observed in Patagonia that the natives all had far better vision than the Europeans. In a civilization without eyeglasses, the genetic ability to produce good eyesight would be well maintained.
So I think you have a good point for homo sapiens, but we're increasing the defects in our gene pool through articial rather than natural means, usually medically related means. We even do the same thing for our pets. For instance, I believe german shepherds have a genetic defect that causes hip problems, but we treat the hip problems and allow the dogs to reproduce. Of course, it was humans who bred german and shepherds and all other dogs from wolves, anyway, so perhaps this is too artificial an example. But you probably get the idea.
In the wild, medical means of alleviating the effects of genetic defects are not available, and genetic defects are filtered out, meaning the affected individuals do not survive to produce, or if they do, they produce fewer offspring than unaffected individuals.
And what I am saying is that this means that evolution is really impossible, since not only does speciation lead to decreased genetic variability, but the passing on of diseases in the population leads to overall lack of vigor that all by itself tends to extinction rather than to anything that could produce a healthy species as evolution implies must happen.
You say that evolution is impossible, and I grant that your misunderstanding of evolution is impossible. This is representative of too deep a misunderstanding to take the time to correct. I know that's a copout, I'm criticizing without providing the proper counterpoint, but I am pressed for time right now. Please give me a pass on this for now and I'll try to come back to it later.
So far in this discussion there have been no examples of these, only examples of "neutral" mutations that cause disease.
I don't think we should let any formal definitions of "neutral mutations" get in the way of understanding. Whatever those definitions might be, I think your approach makes more sense. Describing as neutral a genetic defect that adversely affects the ability of an organism to produce offspring does not make any sense to us laypeople.
I'm addressing a supposed "neutral" mutation, two of them, both causing disease. The supposed "good" mutations are pretty much a wishful fantasy so far.
Haven't examples of good mutations been provided for you in the past? Anyway, one common type of good mutation is caused by gene duplication. Let's say there's a gene that provides a beneficial protein, say a protein involved in muscle endurance. Now there's a mutation that duplicates this gene, and so muscle cells suddenly start producing twice as much of this muscle endurance protein. That's an example of a beneficial mutation.
Any particular gene can experience many different types of mutation, from simple nucleotide replacement to complete inversion to complete removal. While most potential genetic mutations are either harmful or neutral, some mutations are improvements, and the probability that these mutations will happen is not zero. Hence, given time they are inevitable, and to the extent that they provide an advantage they will propagate throughout a population.
--Percy

This message is a reply to:
 Message 157 by Faith, posted 08-19-2006 3:02 AM Faith has replied

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nator
Member (Idle past 2247 days)
Posts: 12961
From: Ann Arbor
Joined: 12-09-2001


Message 165 of 218 (341350)
08-19-2006 11:23 AM
Reply to: Message 157 by Faith
08-19-2006 3:02 AM


quote:
Far from ignoring the point, this IS the point. Since the defective genes are passed on we have a state of increasing genetic disease in the population.
But if that disease does not hinder reproduction, it doesn't matter with regards to reproductive fitness of the population, as long as the environmental pressures remains the same.

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 Message 157 by Faith, posted 08-19-2006 3:02 AM Faith has replied

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