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Author | Topic: front loading: did evos get it backwards | |||||||||||||||||||||||
BeagleBob Member (Idle past 5699 days) Posts: 81 Joined: |
quote: As a material cause, yes. As an ancestral cause, no. You're arguing on a chemical level, which has no bearing on the biological subject of evolution.
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deerbreh Member (Idle past 2914 days) Posts: 882 Joined: |
quote: No that would not make them related. Common genetic ancestry is what makes living things related. Elements are not genes. The TOE has nothing to say about how life began. Edited by deerbreh, : typo correction.
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randman  Suspended Member (Idle past 4921 days) Posts: 6367 Joined: |
You're arguing on a chemical level, which has no bearing on the biological subject of evolution.
Actually it does. First off, chemistry plays a significant role in DNA as well as physics. Secondly, the idea he's presenting is that commonalities can be explained by the fact creatures were created from the same source, the earth, rather than evolving from a theoritical (almost mythical) common ancestor.
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BeagleBob Member (Idle past 5699 days) Posts: 81 Joined: |
quote: Of course it does, but when you speak of chemistry totally divorced from biology as ICANT did, it doesn't make much sense. I really can't see the central point that she's trying to make.
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randman  Suspended Member (Idle past 4921 days) Posts: 6367 Joined: |
The thread isn't about parsimony, wk, and I still see no relevance here as far as this thread.
By parsimony we assume that identical or very high identity genetic features only arose once. If such a feature is shared by 2 species we assume it was present in their common ancestor. Except of course when evos don't, and then they call it convergent or parallel evolution, right?
I would suggest that given how few species most of the common LCA genomic estimates are based on, and the ever increasing number of sequenced genomes, we must expect to see increases in the size of the estimated LCA genomic complement. Do you disagree with this analysis? If so why?
Isn't that in agreement with my OP and what front loaders predict? I don't see why you are making a fuss out of parsimony unless you think parsimony is wrong and leads to an incorrect and inflated estimate of the size the LCA genome. Is that what you are saying?
Rubbish. There is no single front loader model So what? There is no single evo model either, but there are general commonalities of evo models. It appears this is a red herring you are throwing out for some reason, at least from my perspective. ND is gradualistic and does predict what I have stated already in terms of morphological and genetic evolution roughly paralleling one another, which as I stated before, is why evos were so startled and shocked to find the data disagreeing with their expectations.
Again you say something scientifically nonsensical. The latest common ancestors aren't the most primitive organisms. I've not mixed anything up. Once again, you are doding the point. Te comment "most primitive" is relative to the creatures that followed the LCA, not the theoritical and I might add mythical first common ancestor. Also, please don't keep trying to move the goal-posts. No one said there is a 1 to 1 parellel between morphological and genetic evolution, but that they "roughly" parellel, and regardless of what you or anyone says, this is what ND says. It is gradualistic, not saltational, nor Lamarckian, and it does posit that random mutations are adapted via natural selection thus coupling the 2 together. As such, it predicts as evos expected that the more primitive LCAs (as opposed to the species that supposedly followed) would be more primitive genetically. That's why they were surprised and consider it paradoxical that this expectation didn't pan out. On the coral paper, why do you think they consider the findings "paradoxical"? Why did scientists expect to find the opposite? Could it just be that's what evo theory predicted?....hmmm
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randman  Suspended Member (Idle past 4921 days) Posts: 6367 Joined: |
Well, it's not totally divorced. He's saying biology is formed from the earth's chemistry.
In general, I think he has a good point even if you are not a creationist. There are certain constraints and put another way, directives, about how biological creatures, DNA, etc,....are made-up. Evos took too simplistic an approach and insisted all commonalities are the result of common descent with their massive exceptions of parallel and convergent evolution (which imo doesn't explain the data that well) and said that's all there is. In reality, specific features and even specific mutations are dictated by the principles of chemistry and so would arise, if evolution even occured as evos think, independently anyway based on the constraints of chemical properties. Of course, that doesn't mean they were not simply created which explains it as well. In other words, all these similarities evos posit as smoking-guns of common descent are not actually smoking guns at all. Heck, there are even studies showing viruses introduced tend to create mutations in the same loci. Evos insist that the only explanation is common descent, but really medical studies indicate otherwise. Let's don't go there because it would be a different thread, but the main point is that chemistry plays a huge role in the appearance of similarities in biological creatures.
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Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
Except of course when evos don't, and then they call it convergent or parallel evolution, right? That depends on what you consider a feature. If you look at morphological traits then you are correct if we consider similar traits, the question is whether something similar is the same as something identical. We think that proteins are homologous because of their shared sequence identity not merely because they perform the same function. Therefore similar functional morphological traits, as we see from convergent evolution, need not have a similar genetic basis. Similarly parallel evolution may not have a similar genetic basis, or perhaps I should say identical genetic basis as the same gene can be affected in a multitude of different ways and different mutations on the same gene could be considered a similar genetic basis. If you have some clear examples of parallel or convergent molecular evolution I would be very interested. There are several cases, such as armor changes or spine loss in Sticklebacks which show that the same genes can be identified in parallel evolution, but offhand I can't think of any examples of identical mutations. Your argument stands for morphological phylogenies however, which is why we don't ideally base phylogenies on single traits but on a wide range. The principle is still one of parsimony but the fuller the picture the more outlying convergent traits between distant species require more changes to be incorporated into a common ancestor. To explain further, if we have very similar characteristic which evolves multiple times, lets take for example trap jaws in spiders, see here for a phylogeny of spiders showing the occurence of trap jaws, then a parsimonious explanation should involve the least changes possible. The basis of the original tree is genetic sequences rather than morphology. You can see that for the trap jaw trait to be the result of common ancestry, even in the more closely related Ponerinae and Ambyloponinae clades, we would be requiring the loss of the trait at least twice. Two losses of the trait is no more parsimonious than two gainings of the trait, which we require in the absence of common ancestry, when we go to the more distantly related clades you would need as many as 6 independent losses of the trait compared to 3 independent gains under the assumption that it isn't commonly derived. Perhaps I simplified too much and should have caveated my statement with, 'all other things being equal'.
Isn't that in agreement with my OP and what front loaders predict? No, because there is a world of difference between being more complex than the previously estimated LCA genome and being as complex or more complex than any existing descendant species.
I don't see why you are making a fuss out of parsimony unless you think parsimony is wrong and leads to an incorrect and inflated estimate of the size the LCA genome. Is that what you are saying? If you had understood any of what I have been saying about parsimony, or even understood the concept itself, you would see that parsimony will tend to underestimate the size of the LCA genome, especially when it is only estimated from a few fully sequenced genomes. This doesn't mean that the true LCA genome would have been as complex or more complex than the genome of any existing descendant species. What I have emphasised time and again is that with parsimony we would only expect to see the LCA genomic complement expand as more species are added. Now were extensive convergent genetic evolution or even protein evolution, to occur then you would be right to suggest that in fact our parsimonious reasoning could lead us to overestimatethe gemonic complement of the LCA. However, as with the trap jaw trait in my example as we added more species, in this case their genomes, to our phylogeny the less parsimonious and overestimated LCA would become. As yet I am aware of no compelling evidence for significant parallel or convergent genetic evolution producing identical genetic bases for traits. I would consider substantive evidence of such a phenomenon being widespread to be quite good evidence for some sort of 'hidden' information form of front loading. The 'super genome' form of front loading produces lots of non-parsimonious tress as shared genetic traits from distant species would require multile independent losses in various species not sharing that trait despite its presumably having been present in the supergenomic LCA.
So what? There is no single evo model either, but there are general commonalities of evo models. Good point, what I am saying is that there aren't even these commonalities between 'front loader' models. The predictions of a 'supergenome' type front loading are completely opposite to those of a 'hidden information' type front loading argument or somone like the writer at telic thought who thinks that 'front loading' consists merely of the de novo creation of an organism with the potential to evolve further complexity. In fact only the 'supergenome' form of front loading seems to agree with your prediction of a LCA as complex or more complex than any descendant species, the others would tend to agree more with the standard evolutionary models.
ND is gradualistic and does predict what I have stated already in terms of morphological and genetic evolution roughly paralleling one another, which as I stated before, is why evos were so startled and shocked to find the data disagreeing with their expectations. Enormous hyperbole to describe your own totally unsubstantiated interpretation of data.
I've not mixed anything up. Once again, you are doding the point. Te comment "most primitive" is relative to the creatures that followed the LCA, not the theoritical and I might add mythical first common ancestor. How on earth could anyone get that from you writing, 'the most primitive organisms of the latest common ancestors'?
As such, it predicts as evos expected that the more primitive LCAs (as opposed to the species that supposedly followed) would be more primitive genetically. That's why they were surprised and consider it paradoxical that this expectation didn't pan out. Except you are once again storming ahead of the evidence. The evide hasn't failed to 'pan out'. As I seem to keep having to reiterate a more complex LCA than previously estimated is by no means an LCA as complex or more complex than any of its descendant species. If you think you actually have some evidence showing an as complex or more complex genome then present it. Don't just keep going, 'but look how surprised these evos were!!!!!', it isn't an argument or at least it isn't a good argument.
On the coral paper, why do you think they consider the findings "paradoxical"? Why did scientists expect to find the opposite?
Because, as you say, there is a tendency to expect simpler morphologies to correspond to simpler genomes, and previous estimates have predicted simpler genomes for the metazoan LCA, that much is quite correct. It's where you go from there, leaping ahead of the evidence, that is problematic.
Could it just be that's what evo theory predicted? That's what the current models of the metazoan LCA had predicted. I think I need to point out that it would by no means contravene evolutionary theory to have a common ancestor to a clade like the metazoa which was more complex than its descendants. What it would contradict are all of our current models of the evolutionary history of life on earth, which are principally based on parsimonious assumptions. It would contradict evolutionary theory if the LCA were to have fully developed genetic networks for the development of structures which the LCA did not posses. I know that is how you have tried to skew the A. millepora (I think before I was spelling that millipora, like the water filters) research but it just won't go that far. In my reply to you on the criticising neo-darwinism thread, see my Message 263, I describe known alternative roles for the genes 'associated with highly differentiated nervous systems', which don't have anything to do with nervous systems but with very early stage embryonic development. TTFN, WK
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deerbreh Member (Idle past 2914 days) Posts: 882 Joined: |
quote: First off, the fact that chemistry plays a significant role in DNA (duh - of course it does, DNA is a molecule, after all) in no way validates the claim that being made of the same elements is equivalent to sharing common ancestry. That is just bad logic and it would be really off topic to go into it. The argument that commonalities can be explained by the same creator using the same materials - well yes the logic is a little better there - but 1) that is not what was said and I think you are putting words in the mouth of ICANT. and 2)this argument, while attractive on the surface, is quite easily refuted by studying that other occurance which you seem to think is a problem for the TOE - convergent or parallel evolution. In fact, what parallel evolution shows is there is often more than one way to solve many problems presented by natural selection - exactly what you would expect from evolution acting on different populations of organisms but not what you would expect from a common creator using the same materials. Edited by deerbreh, : typo Edited by deerbreh, : another typo
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deerbreh Member (Idle past 2914 days) Posts: 882 Joined: |
quote: I call strawman on the whole argument. I have never heard an evolutionary biologist make this argument the way you did here. Make your arguments against the TOE if you can but stick to what it actually says and not your cartoon version. Just because you don't understand convergent evolution (imo you don't, based on your comments here) doesn't mean there is something wrong with the way it explains the data.
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ICANT Member Posts: 6769 From: SSC Joined: Member Rating: 1.6 |
deerbreh writes: The argument that commonalities can be explained by the same creator using the same materials - well yes the logic is a little better there - but 1) that is not what was said and I think you are putting words in the mouth of ICANT. I was walking very softly as we are in a science thread.
That would mean we have a common place of origin.
Message 45 If we trace life back to the simplest form we have a single cell critter that is supposed to have come from a chemical reaction of amino acids pounded by lightning or at least some form of coming to life. Could you please explain the difference in everything coming from this single cell creature that came from a chemical reaction and what I proposed. I am just a dumb old Bible Thumper so explain for those with no knowledge of the process. Thanks andGod Bless, "John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."
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randman  Suspended Member (Idle past 4921 days) Posts: 6367 Joined: |
Just lost a massive post with several papers linked....arrgghh!
So I will cut to the chase and come back with examples of convergent mutation and explain why parsimony isn't the issue later.
That's what the current models of the metazoan LCA had predicted. But the prediction was wrong, right? What was the basis for that model? Btw, I'll address parsimony briefly. If this was due to parsimony causing an underestimate of the LCA's genome, it wouldn't be such a "surprise", "shock", and considered "paradoxical."
similar functional morphological traits, as we see from convergent evolution, need not have a similar genetic basis. As yet I am aware of no compelling evidence for significant parallel or convergent genetic evolution producing identical genetic bases for traits. I would consider substantive evidence of such a phenomenon being widespread to be quite good evidence for some sort of 'hidden' information form of front loading. I can near guarantee evos won't accept it or anything as evidence for front loading, at least for awhile, but addressing the 2 larger points above. Is there any evidence one way or another yet? I thought we went over this before and the conclusion was the genetic data wasn't there yet to say, for example, if genetic convergent evolution was the reason, say, Marsupials and Placentals share common traits. Moreover, I pointed out that either way it is problematic for evolution and incidentally, evos will argue either result fits Darwinism. If there is convergent genetic evolution, they will say, as you did in one example, there is "deep homology" or some such, and if there is not, they will say all the better. But regardless, do you not expect on the whole that similar traits between Marsupials and Placentals will share similar genes expressing those traits? And wouldn't that be, according to you, evidence of front loading per your comment above? I've got more but need to post this for fear I lose it again.
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deerbreh Member (Idle past 2914 days) Posts: 882 Joined: |
quote: Simple. A random collection of elements does not a common ancestor make. A single cell containing DNA might, on the other hand. There is no ancestor before the first ancestor, in other words. Edited by deerbreh, : clarity
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deerbreh Member (Idle past 2914 days) Posts: 882 Joined: |
quote:On the whole, we would expect them to share similar genes, yes, because in fact marsupials and placentals do have a common ancestor. But in the case of traits resulting from convergent evolution, no.
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ICANT Member Posts: 6769 From: SSC Joined: Member Rating: 1.6 |
deerbreh writes: Simple. A random collection of elements does not a common ancestor make. A single cell containing DNA might, on the other hand. There is no ancestor before the first ancestor, in other words. I am kind of thick headed so bear with me on this. I got a pool of chemical elements that produces a single cell life form over a long period of time this life form produces all life forms. I got a pile of dirt full of chemical elements that produces all lifeforms these life forms produce life forms. I really don't see the difference. But I better leave it there. God Bless, "John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."
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randman  Suspended Member (Idle past 4921 days) Posts: 6367 Joined: |
So you would consider it evidence against Darwinism if it can be shown similar genetic sequeces for similar traits, you know, the ones credited to convergent evolution?
Is that your position?
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