|
Author
|
Topic: John A. Davison: Is Evolution Finished?
|
nosivad
Member
Member # 767
|
posted 19. March 2004 14:10
Dear Dr. Paul Lucas, I specifically indicated that a new species whose natural origin was known would be considered that if the presumed new species was unable to produce fertile offspring with its known parents. It is interesting that you would cite Drosophila which is the material that Dobzhansky chose. Of course his attempts were a total failure as he subsequently admitted. Incipient species are not species. The cytogenetic origin of many organisms which are regarded as new species remains in doubt. Autopolyploidy and allopolyploidy are very special cases and have nothing to do with selection. My highly specified claims were as follows. It has yet to be demonstrated that any organism reproducing by obligatory sexual means is capable of evolution beyond the subspecies. Even the most intense forms of artificial selection have failed, and I stick to my claims. It is selection that is the failure, whether natural or artificial. Sexual reproduction is antievolutionary, which is probably why it largely prevails. Unfortunately, since sexual forms are incapable of progressive evolution, they are nearly all doomed to extinction as the current scenario so convincingly demonstrates. Show me a new sexually generated species whose ancestor is known with certainty and I will recant. Until then let me live in what you apparently regard as my fantasy world.
As for Sidney Fox whom you cite at great length, I was his colleague at Florida State University when he was doing his experiments with proteinoids. I distinctly recall his great enthusiasm when he called us all to view his proteinoid spheres some of which seemed to be dividing. To suggest that those observations have anything whatsoever with the origin of life is pure fantasy. I am sure Sidney would agree with me if he were with us now. As for abiogenesis generally I will stick with Redi, Spallanzani and Pasteur. Selection as a creative device is without foundation as was obvious to Punnett, Bateson, Osborn, Goldschmidt, Berg and Grasse as well as myself. It serves only to preserve the status quo. I doubt very much if macroevolution is ocurring in hydrothermal vents or anywhere else. Such claims are without foundation. This is a trivial matter but I was awarded my Doctorate in 1954, so the title Mr. is at least inappropriate.
[ 19. March 2004, 14:17: Message edited by: nosivad ]
IP: Logged
|
|
Moderator
Administrator
Member # 1
|
posted 20. March 2004 02:39
Charlie, Paul,
You both need to take a "tone" time-out. Many of your comments are unprofessional and out of line for our board. So--tone it down. Especially avoid comments along the lines of "That's not what I said--now tell me how you would test X" (unprofessional to be treating a fellow scientist in such a condescending manner) or "Apparently Davidson has not even done a cursory search of the literature" (unprofessional because surely Davidson HAS done such a search, and he may find these references unpersuasive for any number of reasons). Once again--tone down, be respectful and curteous, or you may face banning, either temporary or permanent. Paul, if you want your posts to remain up, please edit them to refer to Dr. Davidson as "Dr." instead of "Mr.". Otherwise, I will delete them.
The friendly
Moderator
[ 20. March 2004, 02:43: Message edited by: Moderator ]
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 20. March 2004 03:33
The moderator introduced my paper "Is Evolution Finished?" which is the subject of this discussion. In order to keep things on track, I am happy to respond to the substance of that paper. If there are inaccuracies in it please call my attention to them as I haven't yet received the proofs. Much of what is being brought up now was presented earlier in my defense of "An Evolutionary Manifesto: A New Hypothesis For Organic Change" and I suggest that thread should be consulted to avoid redundance. It ran nearly 180 posts and I believe I responded to every challenge that was presented. If anyone wants to reactivate that thread I will continue to defend my position. I am now prepared to do the same with this paper. I only ask that the questions be as specific as possible. My handle is nosivad which is davison spelled backward. Someone once indicated that was very appropriate to my perspective, an observation with which I most certainly agree.
[ 20. March 2004, 03:39: Message edited by: nosivad ]
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 20. March 2004 10:15
Charlie,
If you want to discuss moderating decisions please send an email to moderator@iscid.org. These boards are not for justifications or for arguing about moderation (I won't be dragged into a give-and-take about your tone in your emails).
The problem is not that you "asked" for Dr. Davidson's comments, you demanded them in a rude and discourteous fashion. If all you had done was to ask a question, the problem would never have arisen. The entire tone of your post was negative and personal--and against the standards we try to uphold here at Brainstorms.
If you have something useful to say, please do so in a courteous fashion (something you again failed to do in this post, which is why it was deleted). Personal insinuations and rude demands are not welcome here.
The friendly
Moderator
[ 20. March 2004, 12:43: Message edited by: Moderator ]
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 20. March 2004 12:52
Chalie d. I am unable to answer questions concerning which neither you nor I have any certain knowledge. Since we don't even know how many times mammals were produced from reptiles, don't expect me to characterize the problem any further.
Yes, I have dismissed Darwinism for the several reasons I, and others long before me, have advanced. It is an observational and experimental disaster just as is Lamarckism is. Using the time honored method of the elimination of alternatives, I am now firmly of the opinion that evolution, exactly like ontogeny, has been (past tense) largely, if not completely, a prescribed process, resulting from the organized derepression of predetermined genetic information as is so obviously the case for ontogeny. Ontogeny and phylogeny are integral parts of the same organic continuum. I have presented this hypothesis in my 2000 Rivista paper "Ontogeny, Phylogeny and the Origin of Biological Information", an online version of which is available on my home page. www.uvm.edu/~jdavison
Incidentally, there is a glaring misrepresentation in the text of the online version which I corrected in the published paper. I wonder if you are anyone else can find it. That way I can at least be certain that the paper has been read.
[ 21. March 2004, 01:02: Message edited by: nosivad ]
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 20. March 2004 19:09
quote:
nosivad:
Chalie d. I am unable to answer questions concerning which neither you nor I have any certain knowledge. Since we don't even know how many times mammals were produced from reptiles, don't expect me to characterize the problem any further.
Thanks for answering the question. Although of course "certain knowledge" is an elusive concept in science, I am quite content with the provisional inference of modern evolutionary biology, based on consistent molecular, anatomical and paleontological evidence, that mammals are very likely monophyletic. On the other hand, I gather from your answer above that the semi-meiotic hypothesis cannot address whether humans and naked mole rats are just subspecies of the same semi-meiotic species, or if every single mammalian species originated independently from reptilian ancestors, and they all happened to discover the same sex determination mechanism. That settles it.
If you don't mind, I'll have ignore the rest of your post which accuses the scientific community (and myself) of utter incompetence and malignant persecution. If I didn't, I'd likely be engaging in the kind of professional discourtesy which is frowned upon on this board.
IP: Logged
|
|
Moderator
Administrator
Member # 1
|
posted 20. March 2004 19:37
nosivad,
You also need to be careful about taking jabs at Darwinists. In general your posts are fine, but occasionally you say things that are genuintely unfair; other things you've said in response to being attacked by Charlie and Paul. This last post is mostly negative and also rather unfair (comments that insinuate Darwinism is "a complete myth" or "disaster" or "Godless".) Certainly, one might hold these views without expressing them in flippant ways that will only further hostile feelings. These comments do nothing to further discussion of the content of your paper and serve to incite hostile responses (as has happened on this thread).
So--to be fair, I want to ask that you edit your previous post to remove the blanket statements about Darwinists and Darwinism. Let's strive to uphold a respectful, thoughtful forum where ideas can be discussed in positive, insightful ways without descending into stereotypes and ad hominems. I think your ideas are highly worthwhile for discussion--let's avoid the flippant jabs that tend to cause hostile responses.
Thanks.
the friendly
Moderator
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 21. March 2004 01:39
I thank the moderater for reminding me of my frustration. I hope removing my inflammatory remarks will serve to promote a more rational discussion, but frankly I doubt it. My experience on this and other forums serves to further reinforce the conclusions set forth in William Wright's book - "Born That Way". We are all very hard wired. Even those very well documented findings have been largely ignored by both the Creationists and the strictly materialist evolutionists (Darwinians) for the very reasons indicated in the title - "Born That Way". What we are witnessing is the age old conflict of how man is going to regard his position in the universe. Is he an accident as Dawkins and Gould would have us believe, or is he the inevitable product of a plan? I happen, with Robert Broom, to be convinced of the latter and with the Anthropic Principle generally. I also agree with Leo Berg that just as chemistry and physics have been determined by law, so has every aspect of both ontogeny and phylogeny. I have reached that position after a careful consideration of every line of evidence which I feel I am confident to comprehend. In any event, I am sure these issues will not be resolved by majority vote. Nothing in the history of science ever has.
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 21. March 2004 02:07
Charlie d. I'm sorry but that does not settle anything. It is perfectly possible that any diploid organism, reproducing sexually, could on occasion reproduce semi-meiotically. It could be happening right now for all I know. The great advantage of this possibility is that it creates a new chromosome homozygote instantly and does not require what has always been a glaring weakness of the sexual (Darwinian) model - the requirement for evolutionary change to occur in small isolated populations. Goldschmidt clearly recognized this weakness in the Darwinian scheme but was unable to formulate a cytogenetic explanation for what is a universal characteristic of diploid organisms. The chromosomes with the exception of the sex chromosomes occur as homologous pairs. The semi-meiotic hypothesis presents a mechanism whereby this could be generated at any time in any population in a single cytogenetic event. The first meiotic division is ideally suited to the task because it is universally the case that the sister (identical) strands remain together in the first meiotic division. The potential for the rare event should never be ignored, especially since it is subject to experiment.
"Treasure your exceptions". William Bateson
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 21. March 2004 09:22
quote:
Charlie d. I'm sorry but that does not settle anything. It is perfectly possible that any diploid organism, reproducing sexually, could on occasion reproduce semi-meiotically. It could be happening right now for all I know.
I guess evolution is not really finished, then. Fair enough, I guess. Also, current phylogenetic trees would hold as long as any parent species would give rise to a daughter species through semi-meiosis, instead of conventional mechanisms. So, say, for the hominid lineage some hominoid primate would have semi-meiotically originated an australopithecine, which in turn would have semi-meiotically originated habilis, and this erectus, from which sapiens would have been semi-meiotically derived (of course all these steps had a lot of intermediate species - this is just for simplicity). Each semi-meiotic step would imply a significant enough cytogenetic change to result in karyotypic incompatibility (like a translocation, or large chromosomal inversion). Do I interpret this correctly?
My original point however was about the implications of semi-meiotic speciation requiring that a new species would have to rediscover sexual reproduction mechanisms from scratch, as you indicated in a previous post. As you seem to indicate now that you do believe all current mammalian species are indeed separate species, and may well be linked by common descent, one would have to conclude that all mammals just happened to discover the same system of genetic sex determination after semi-meiotic speciation. A rather amazing coincidence - but fortunate enough for sex geneticists! quote:
The great advantage of this possibility is that it creates a new chromosome homozygote instantly and does not require what has always been a glaring weakness of the sexual (Darwinian) model - the requirement for evolutionary change to occur in small isolated populations.
That of course is not really a "requirement" of darwinian evolution. For instance, ring species show how speciation can occur by divergence of large, non-isolated populations. There is quite a bit of recent (last 20 years or so) literature about speciation mechanisms that is very interesting in this respect.
But going back to the semi-meiotic hypothesis, every new species would originate as a single individual. So, initially, the genetic diversity of a species would be limited to 2 alleles per locus, and all the polymorphisms currently observed in a species would be derived after speciation. Correct?
[ 21. March 2004, 09:23: Message edited by: charlie d. ]
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 21. March 2004 11:24
charlie d
Every heritable genetic change of any sort originates in the germinal line of an individual organism. That is the reason I have insisted all along that the individual is the unit of evolution rather than the population. I fully realize that this is in contrast with population genetic theory. The important point as I see it is that when we compare ourselves to our living primate relatives we see exactly what Goldschmidt predicted 64 years ag - chromosome restructurings. These cannot occur gradually and it seems to me they must have originated in a particular creature. Furthermore there is no evidence to indicate that such events involve the addition of genetic information, which is why I have come up with the Prescribed Evolutionary Hypothesis. I don't understand why sexual cytogenetic mechanisms have to reinvented. I specifically postulated in the Manifesto that semi-meiosis and full meiosis could coexist and on reflection I see no reason why macroevolution could not recur although there is no reason to assume that. I also postulated that the vertebrate gonad, which is now a sterile epithelium, may have been the original site of semi-meiosis. There is a curious medical observation that supports this possibility. One of the more common ovarian teratomas consist of growths containing primarily the ectodermal derivatives of hair and teeth. Occasionally more than one such tumor can occur in a woman. I recall reading of a case of a womam who had two such tumors, one blond and one brunette. I presume these were produced from the gonadal epithelium. If that is so they most likely were produced semi-meiotically to indicate that the woman was heterozygous for hair color and probably a brunette herself. Perhaps Dr. Lucas can track down this literature as I have managed to lose the reference.
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 21. March 2004 14:27
quote:
Every heritable genetic change of any sort originates in the germinal line of an individual organism. That is the reason I have insisted all along that the individual is the unit of evolution rather than the population. I fully realize that this is in contrast with population genetic theory. The important point as I see it is that when we compare ourselves to our living primate relatives we see exactly what Goldschmidt predicted 64 years ag - chromosome restructurings.
Sure, but relatively limited, given the evolutionary distance. There is one major chromosomal fusion in the H. sapiens compared to other apes. I am not aware of any other large chromosomal rearrangements. Wouldn't semi-meiosis predict at least one major rearangement/speciation event? quote:
I don't understand why sexual cytogenetic mechanisms have to reinvented. I specifically postulated in the Manifesto that semi-meiosis and full meiosis could coexist and on reflection I see no reason why macroevolution could not recur although there is no reason to assume that.
But wouldn't semi-meiosis oblifgatorily give rise to a female in mammalian organisms? quote:
There is a curious medical observation that supports this possibility. One of the more common ovarian teratomas consist of growths containing primarily the ectodermal derivatives of hair and teeth. Occasionally more than one such tumor can occur in a woman. I recall reading of a case of a womam who had two such tumors, one blond and one brunette. I presume these were produced from the gonadal epithelium. If that is so they most likely were produced semi-meiotically to indicate that the woman was heterozygous for hair color and probably a brunette herself. Perhaps Dr. Lucas can track down this literature as I have managed to lose the reference.
Yes, most teratomas are diploid (some polyploid, IIRC), but derived from a haploid germ cell (after the first meiotic division). I am not sure a teratoma is the prototypical "hopeful monster" though.
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 21. March 2004 15:18
charlie d
There are at least a dozen chromosomal rearrangements distinguishing us from chimpanzees alone. I refer you to Figure 2 in the Manifesto for verification. That figure is taken directly from the paper by Yunis and Prakash. The most similar chromosome is the X chromosome, precisely what one would expect for a gynogenetic mechanism. The least similar chromosomes are the Y chromosomes again exactly as one might expect if the males were secondarily produced, which incidentally is precisely what N.N. Vorontsov suggested when he wrote -
"Against the background of these facts it is unclear whether the male species of different groups are homologous or not; they appear to be nonhomologous"
Again I refer you to the Manifesto where all this has been already discussed at length.
As for semi-meiotic products being female,
it simply is not so. Again I refer you to the Manifesto and the experiments of Loeb, Hertwig and Nace. Both male and female frogs are produced semi-meiotically. Furthermore the XX males produced are fertile and can when crossed with XX females again produce both sexes with approximately 20 females to every male. There is thus no question that the potential to produce both sexes in contained in the female vertebrate genome. Since these experiments have not been tried in mammals, we simply do not know. Besides, since macroevolution is no longer apparently occurring it is of no consequence in any event. Apparently, judging from your questions, you are not familiar with the literature which I have summarized in my published papers and the Manifesto.
I am also not at all convinced that the teratomas I mentioned have originated from contemporary germ cells. It is certainly possible that they originate directly from the gonadal epithelium, which apparently is no longer competent as a source for gametogenesis. Incidentally, a germ cell is not haploid after the first meiotic division as you claimed. It is diploid and does not become haploid until the completion of meiosis II. That indisputable fact lies at the heart of the semi-meiotic hypothesis. If the sole purpose of meiosis was to produce haploid gametes we can be certain that Natural Selection, that wonderfully totipotent evolutionary force, would never have allowed gametogenesis to proceed as it so universally does. There would be a single reduction division.
[ 21. March 2004, 15:31: Message edited by: nosivad ]
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 21. March 2004 23:48
quote:
There are at least a dozen chromosomal rearrangements distinguishing us from chimpanzees alone. I refer you to Figure 2 in the Manifesto for verification. That figure is taken directly from the paper by Yunis and Prakash.
nosivad, the Yunis paper, though certainly a classic, is from 1982. Cytogenetic techniques have since improved quite a bit, and as you know has gone well past G-banding. More recent works have been published using the more accurate and less artifact-prone FISH and chromosome painting techniques (eg, Muller and Wienberg, Hum Genet. 109, 85, 2001). According to those results, large chromosomal rearrangements actually seem to have been quite rare in hominoid evolution. Comparing the human karyotype to that of other hominoids, only the chr. 2 fusion looks like unquestionably very significant, with other alterations being more subtle and, as far as I can tell, of uncertain functional significance (usually involving pericentric heterochromatin expansions/deletions or inversions). For 14 chromosomes (13 autosomes and the X) humans even retain what is likely the ancestral hominoid chromosome structure - that's quite impressive, if you ask me. Of course, this is not meant to diminish the role of chromosomal recombination events in evolution, which is indeed well known. quote:
The most similar chromosome is the X chromosome, precisely what one would expect for a gynogenetic mechanism. The least similar chromosomes are the Y chromosomes again exactly as one might expect if the males were secondarily produced, which incidentally is precisely what N.N. Vorontsov suggested when he wrote -
"Against the background of these facts it is unclear whether the male species of different groups are homologous or not; they appear to be nonhomologous"
Again I refer you to the Manifesto where all this has been already discussed at length.
Thankfully, our understanding of sex determination and Y chromosome structure also has improved since 1973, when that quote is from. Not only we have likely identified most Y chromosome coding sequences, including Y-specific genes such as SRY and a bunch of others, but people were lso able to phylogenetically track when and how some of those Y chromosome genes originated (eg, through transposition events from other chromosomes). Skaletsky et al (Nature 423, 825, 2003) have a nice description of the structural features and phylogenetic changes of Y-specific chromosome sequences. Putting it succintly, de novo generation of the Y chromosome, as you propose it, starting from an XX female individual after each semi-meiotic speciation event would imply:
1. De novo massive loss of X chromosome material from a single X chromosome (not the other) - such loss has to be coordinated and almost identical in all species, since the pseudoautosomal region (shared between X and Y) is quite conserved.
2. De novo independent generation and massive expansion of vast amounts of repetitive DNA elements on the new Y chromosome. These independently generated Y-specific repetitive elements somehow have to end up being structurally related in phylogenetically close species.
3. Independent import in multiple species of the same exact genes from other chromosomes, in the same order, followed by rapid diverge sufficient to simulate ancient phylogenetic separation of the paralogues, synchronized through related species according to their phylogenetic distance as measured on autosomal sequences.
4. De novo functional differentiation of the whole testes-determining genetic developmental program, in exactly the same fashion though all species.
Not exactly a parsimonious model. quote:
Again I refer you to the Manifesto and the experiments of Loeb, Hertwig and Nace. Both male and female frogs are produced semi-meiotically. Furthermore the XX males produced are fertile and can when crossed with XX females again produce both sexes with approximately 20 females to every male. There is thus no question that the potential to produce both sexes in contained in the female vertebrate genome. Since these experiments have not been tried in mammals, we simply do not know.
Yes yes, every kid who has seen Jurassic Park knows that frogs have rather flexible sex determination. Why do you think I am sticking to mammals? Indeed, any significant experiment aimed at testing the universal applicability of the semi-meiotic model (rather than its potential as a further anuran oddity) should probably avoid frogs as well. quote:
Apparently, judging from your questions, you are not familiar with the literature which I have summarized in my published papers and the Manifesto.
Sorry, I am not supposed to answer this allegation, as I may violate standards of professional courtesy on this board. quote:
I am also not at all convinced that the teratomas I mentioned have originated from contemporary germ cells. It is certainly possible that they originate directly from the gonadal epithelium, which apparently is no longer competent as a source for gametogenesis. Incidentally, a germ cell is not haploid after the first meiotic division as you claimed. It is diploid and does not become haploid until the completion of meiosis II.
You are certainly correct here, "haploid" is not the right term: these cells are 2n. I was referring to your observation that the teratomas can express recessive alleles - cells after meiosis I can be functionally haploid (both copies of each gene identical). Regardless, teratomas have a unique genetic complement that as far as we know can only be derived from cells after meiosis I, which as far as we know can only be germ cells. If you think other cells can enter meiosis I, that's entirely possible for what I can tell, but the burden of proof is on you. quote:
That indisputable fact lies at the heart of the semi-meiotic hypothesis. If the sole purpose of meiosis was to produce haploid gametes we can be certain that Natural Selection, that wonderfully totipotent evolutionary force, would never have allowed gametogenesis to proceed as it so universally does. There would be a single reduction division.
But of course, no one says NS is totipotent; indeed, its solutions are often cumbersome. Apart from the "accident" model, there may also be more significant reasons for the current meiotic double division mechanism related to the functional constraints imparted on cell division by DNA replication, chromosome condensation, etc. I suggest Cavalier Smith's review "Origins of the machinery of recombination and sex." (Heredity. 88, 125, 2002) as a good starting point on the more recent literature.
[ 22. March 2004, 00:04: Message edited by: charlie d. ]
IP: Logged
|
|
nosivad
Member
Member # 767
|
posted 22. March 2004 02:07
charlie d It is obvious from the tenor of your comments that you have dismissed my views out of hand. Your general perspective is that of the typical Darwinian gradualist, invoking randomly generated genetic alterations as the elements which Natural Selection serves to filter somehow, leading inexorably toward evolutionary change. Natural Selection is and was nothing but a conservative device which serves to maintain the status quo, a conclusion reached in roughly chronological order by St George Mivart, William Bateson, Henry Fairfeld Osborn, Reginald Punnett, Leo Berg, Richard Goldschmidt, Pierre Grasse, and a host of other biolgists including myself. Artificial slection invariably leads to a loss of fitness.
It has yet to be demonstrated that any higher organism reproducing by obligatory means is capable of transcending the species barrier let alone the prospect of ever resulting in a new Genus, Family, Order, Class or Phylum. That incidentally is presumbly the subject of this thread - "Is Evolution Finished?". It is my studied conviction that it is.
Since sexual reproduction is a failure, I have concluded that the primary role for
sexual reproduction is to stabilize the species. This stabilization and loss of evolutionary potential offers an immediate explanation for the undeniable reality that 99% plus of all species that ever existed were doomed to extinction. Why? Because they could not evolve. Cats, Racoons, opossums and squirrels are not even capable of the trivial sort of behavioral evolution that might protect them from their primary urban predator, the automobile.
Since sexual reproduction, being a highly conservative mechanism, has failed, I proposed that it was preceeded by the first of the two meiotic divisions as a creative evolutionary device. The first meiotic division is a perfectly normal form of diploid reproduction and contains in its elements all the necessary features to produce novel chromosome structural homozygotes from any single structural change in any single chromosome in any cell destined to become an oocyte. What we witness in meiosis is the
historical sequence in which the first division had to preceed the second. Once the second became mandatory so did sex and evolution came to a standstill.
Quite independent of this, I am now of the firm opinion that evolution, like ontogeny, has resulted from preformed information which was expressed by derepression. This interpretation remains compatible with the absence of any convincing demonstration that mutations have somehow introduced meaningful information into the genome. I simply don't believe it. Just as all of mathematics, chemistry and physics had been prefomed and predetermined, so apparently have been all of the laws that govern both ontogeny and phylogeny been predetermined. It is in short exactly as Leo Berg so accurately observed- "Nomogenesis or Evolution According to Law".
If you or anyone else wants to continue to adhere to the most failed hypothesis in the history of science, there is nothing I can possibly do to disuade you. I wish you well. Please just leave me to my fantasies. I am in the process of moving so I will not be able to respond at length at least for a little while.
"Here I stand. I can do no other"
Martin Luther
[ 22. March 2004, 02:17: Message edited by: nosivad ]
IP: Logged
|
|
|
Topic Closed
Printer-friendly view of this topic
