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Author
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Topic: John A. Davison: An Evolutionary Manifesto: A New Hypothesis For Organic Change
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Pim van Meurs
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Member # 541
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posted 19. June 2003 12:37
Davison, it seems that there are several problems with your claims. Let me explain
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Charlie d, you seem to be confident that evolution is in progress now.
That confidence is strengthened by the countless examples of evolution in progress right now.
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unlike evolution, gene mutations are reversible.
A common misconception of evolution. In fact several good examples of 'reversible' evolution exist.
Once one realizes that these two concepts are valid the conclusions seem to be obvious.
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Pim van Meurs
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Member # 541
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posted 19. June 2003 12:43
Dear Peter,
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dear Pim,
I recommend you to read Annual reviews of genetics 2002 from cover to cover. You will find out about: 1) Phenotypes are determined by DNA element topology, 2) the specificity of spontaneous mutations (NRM), and 3) a new and better evolutionary hypothesis than the current one.
Interesting assertions. Could you in a few words explain this 'better evolutionary hypothesis' as well as its relationship to the neo-Darwinistic variant called NRM?
Peter claims
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and sometimes (as we know of now) with respect to impoved fitness as a response to the environment
We have gone through your 'examples' and none of these mutations were with respect to improved fitness, rather they were hypermutations in response to "stress" followed by selection by the environment.
So far NRM is not only very simular to Neo-Darwinism but Peter has still failed to provide us with any detailed analysis to show why NRM is 'better' and how NRM can affect common descent inferences.
Looking forward to such an analysis Peter.
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nosivad
Member
Member # 767
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posted 19. June 2003 15:26
Gordon or Pim or whoever. If evolution has been reversible, I ask for specific examples. Simple assertions won't do. As to species definition, I gave you the one offered by a Darwinian. That same Darwinian, Dobzhansky, failed to transform Drosophila experimentally. Apparently you are not satisfied with a straightforward, testable, concrete, physiological criterion. The simple fact is that no one has yet created a species through the most rigorous application of selection, yet the Darwinians continue to claim that Nature blindly realizes that which they are so obviously unable to achieve. I find that notion untenable. I repeat my question - How can that which has been created become the Creator? nosivad
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Argon
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Member # 276
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posted 19. June 2003 17:19
I've been thinking about the idea that speciation or evolution has largely stopped today. I assume that hypothesis is based on some set of observations about the pattern and relationships of life today.
If aliens landed on Earth exactly 5,000,004 years ago and cataloged Earth's biota to the same degree that we've currently done with today's species, how would their observations or conclusions differ? Essentially, how would a snapshot of life of 5, 10, 20 or 100 million years ago suggest that evolution hadn't stopped at those times? What's unique about today?
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Nel
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Member # 614
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posted 19. June 2003 23:23
Charlie d.,
You lifted those sentences out of context. Of course, with your examples, they can be explained without reference to other genes. With my example (Rb-null fibroblasts), it seems to indicate that retinoblastoma is not monogenic.
With respect to Nup96, what I actually said was that hybrid sterility requires interaction with a second gene and therefore it is definitely not monogenic, I don't even think it's a phenotypic trait, and I explained this all in my previous posts. It's as simple as that. I didn't concede that speciation is a simple process, just that two genes not being compatible with eachother may be enough for hybrid sterility in the case of the flies.
Also, where do you get the idea that I'm somehow "giving up"? In fact, your line of thinking seems more like you are "giving up", a simplistic view of the Orr paper would force a scientist to conclude that Nup96 was all that is needed, and therefore the scientist wouldn't bother searching for that other required unidentified gene. Complexity requires more research to uncover all the pieces of the puzzle, it's not "giving up" at all. A good example of this is the main point of my previous posts, that phenotypic traits are not due to genes alone, and it would require a scientist to "give up" when in fact, the causes may be due to things like system dynamics, again, finding those other pieces of the puzzle instead of thinking that genes alone are the cause is the complete opposite of "giving up".
Finally, and I already discussed this as well, it matters very much to Darwinian theory if genes alone are not enough to account for phenotypic origination. My quotes and discussion of the references attest to that. That means that small incremental steps guided by selection is either not enough or irrelevant, as the Harold quote also attests to. Darwin didn't know about genes, but he did posit natural selection as the creator of phenotypic traits. And the modern synthesis tied this to random mutation of genes that confer a selective advantage. So of course it matters, if this is not due to a Darwinian mechanism, then we have to find out what the cause of heritable variation is. As I pointed out, we havn't identified any gene that encodes large amounts of information for development.
I don't think that origination of heritable traits is incomprehensible, but it may be the case that it is. But it would be good if it isn't, but that wouldn't mean that it's not complex, it just takes a lot more research then just saying "it's the result of random mutation and natural selection". If where they come from is not due to any Darwinian mechanism, then this leaves this area wide open for intelligent design research, especially if it is very complex.
I know I've probably said the same thing about 200 different ways, but just trying to get my point across.
For example, there is a lot of interesting discussion here http://www.cds.caltech.edu/~doyle where they actually compare many aspects of Biology to engineering, designed complex systems, like the internet and it's protocols (TCP/IP, HTTP, FTP, etc).
Here is a quote:
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The future of biology also has many parallels with the future of complex engineering systems. Emphasis is now shifting from components and molecules to the study of the vast networks that biological molecules create that regulate and control life. It is our claim, which this article will not attempt to justify, that while biology and technology have different system-level behavior and even more vastly different component parts, the organizational principles that govern the layers of protocols, modules, and feedback that lie in between are far more alike than is commonly realized. LEGO and the Internet are completely unalike, but they share certain essential features involving robustness, protocols, and feedback control, and these essential features are shared with biology. While there are perhaps many ways in principle to interconnect components to make complex systems, very few that are robust and thus likely to
persist and be observed.
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The E. coli chemotaxis system has some remarkable design features, from the modularity and dynamics of the sensors and signal transduction network, to the construction and action of the flagella, to the stochastic search algorithm implemented by “run and tumble” to overcome the inherent limitations in gradient sensing at such small scales. It has been correctly remarked that nothing like this system exists in engineering. Only in bacteria has this particular combination of methods been combined in this particular way, and it will be some time before nanotechnology allows engineers to build micronsize swimming robots. In contrast, all of the known system level organizational principles appear to
correspond to standard engineering practice. Such
similarities throughout biology to engineering control systems have been noted elsewhere.
Of course full discussion of this may be beyond the scope of this thread. The short answer to your question is that we are all probably just feeling up different parts of an elephant we can't see (some are looking at just the genes, others are looking at spatial aspects, etc). The shortest answer to your question is I think we are looking at complex systems that were designed. Finding out exactly how the design works, how the design was implemented, and what design questions we can ask to study the system and how those questions actually help to get the answer to your question, will be a lot of fun.
[ 19. June 2003, 23:45: Message edited by: Nelson_Alonso ]
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charlie d.
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Member # 159
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posted 20. June 2003 08:13
quote:
Nelson:
You lifted those sentences out of context.
I did nothing of the sort. The only part of your entire post I left out was the following, which basically reiterates the same point: quote:
Speaking broadly, all genes work within the context of the organism's genome. However, the distinction between hybrid sterility and a trait is pretty clear. For a trait what matters is that the expression depends on the form of the gene in the context of the organism's genome whereas for hybrid sterility it depends on the form of the gene when combined with the form of another gene in the context of the organism's genome.
I interpret this as: all genes, included those that can be called sufficient to determine a trait, work in the context of other genes in the genome, but genes that determine hybrid sterility cannot be called sufficient to determine the trait, because they must work in the context of other genes in the genome. Whatever. quote:
With my example (Rb-null fibroblasts), it seems to indicate that retinoblastoma is not monogenic.
Fine, but then be aware you are using an unconventional definition of "monogenic". quote:
Hybrid sterility requires interaction with a second gene and therefore it is definitely not monogenic, I don't even think it's a phenotypic trait, and I explained this all in my previous posts.
....
Darwin didn't know about genes, but he did posit natural selection as the creator of phenotypic traits.
You are also using an unconventional definition of phenotype, considering that hybrid sterility is a phenotype of hybrids, and that Darwin never dreamed of positing natural selection as the creator of phenotypes.
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gordon
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Member # 781
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posted 20. June 2003 08:21
I know that excessive quoting and 'off the cuff' responses are frowned upon, but if the moderator will me indulge this once.
Dr.Davison:
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...Simple assertions won't do.
Then in the same post:
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How can that which has been created become the Creator?
The implicit assertion here is that we were 'created', and simple assertions such as that will not do.
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As to species definition, I gave you the one offered by a Darwinian. That same Darwinian, Dobzhansky, failed to transform Drosophila experimentally. Apparently you are not satisfied with a straightforward, testable, concrete, physiological criterion.
You may have provided an accepted definition of species, but it seems at odds with your hypothesis. I did not ask for someone else's defintion, I asked for yours. You say you are content with the sterile hybrid criterion, but as Grasse pointed out, and you acknowledge, chromosomal rearrangements do not always result in speciation, and differing karyotyes, again according to Grasse, are not necessarily barriers to producing viable offspring.
So, your hypothesis seems to 'suffer' from the very 'shortcoming' of Darwinism that you are so uncomfortable with - randomness.
Sometimes meiotic chromosomal aberrations result in speciation, sometimes they do not.
But you only answered a small part of my repeated inquiries.
The logical conclusion of your hypothesis, and from what I have read from you here, is that a new species is born, if I may use the term, instantaneously. Fallout of this, as I have read elsewhere, is the requirement that this one new species prototype then engages in asexual reproduction to establish a population, which then somehow reverts to sexual reproduction.
Is this correct?
If so, what mechanisms have you proposed, found evidence for, and/or tested to account for this?
If this is not correct, how is it that a new monotypic species - a single specimen - which will produce sterile hybrids with its parental stock, can establish itself as a viable population of a new species?
Brainstorming welcome.
[ 20. June 2003, 08:23: Message edited by: gordon ]
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nosivad
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Member # 767
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posted 20. June 2003 08:46
Gordon, if I could answer certain questions, I would. I have indicated that the semi-meiotic and sexual modes could possibly have coexisted. As for the reinvention of males, I think the evidence supports that. Again, that notion is not new with me. Vorontsov, whom I have quoted in my papers and the Manifesto had this to say :
"... Against the background of these facts it is unclear whether the male species of different groups are homologous to each other or not; they appear to be nonhomologous."
I see no evidence of structural homology in the Y chromosomes of chimps, gorillas, orangs and humans. By way of contrast, the X chromosomes seem to be similar if not structurally identical as one would expect of a gynogenetic (semi-meiotic) mechanism. I hope you will understand that I arrived at the semi-meiotic hypothesis entirely through the necessity of abandoning the sexual model. I am not ready to abandon the reality that evolution occurred in the past. At the same time, I see no evidence for macroevolution at present.
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Argon
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Member # 276
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posted 20. June 2003 10:02
nosivad writes:
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At the same time, I see no evidence for macroevolution at present.
If we had arrived on this planet 10,000,004.5 years ago, would we have seen evidence for macroevolution which is qualitatively different from the sort of evidence we see today?
[ 20. June 2003, 10:03: Message edited by: Argon ]
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nosivad
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Member # 767
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posted 20. June 2003 11:40
Argon, the short answer to your interesting question is yes. nosivad
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Argon
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Member # 276
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posted 20. June 2003 11:50
If we need to keep replies short, could you provide details for just one or two particular examples? And this would pertain to what an observer would note if they arrived exactly 10,000,004.5 years ago, or perhaps over any 100-200 year "snapshot" of time in the past.
[ 20. June 2003, 11:52: Message edited by: Argon ]
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nosivad
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Member # 767
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posted 20. June 2003 11:51
Gordon, I am sorry I missed this question in your post. You asked if I think species were instantaneously born. The answer is yes. that is why all extant species are discretely different from one another. I assume that was also true in the past. Also, what is wrong with my use of the term created? Are you or anyone else denying that? While the mechanism may be unknown everything in the universe was somehow produced, made or created, wasn't it?
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nosivad
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Member # 767
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posted 20. June 2003 11:58
Dear Argon, I will let the greatest paleontologist of his day speak for me. "The first bird came from a reptilian egg" - Otto Schindewolf
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Nel
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Member # 614
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posted 20. June 2003 14:53
Charlie, you lifted those sentences out of context, and then you changed the subject, brought in a completely different quote, and then completely misinterepreted it. The difference between a monogenic trait and polygenic trait is that with a polygenic trait a single gene is insufficient, as it is with hybrid sterility. In that quote you cite I stated this quite clearly:
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when combined with the form of another gene in the context of the organism's genome.
I can't make it any clearer than that, but I'll try.
The section that you took out of context was completely different. I was referring to the fact that your Rb examples would not lead anyone to think that it was polygenic because they can be explained without reference to interaction with a second gene, whereas my example seems to indicate that it is polygenic.
Those were two very distinct points.
charlie wrote:
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Fine, but then be aware you are using an unconventional definition of "monogenic".
No, I'm using a conventional definition of monogenic. Not monogenic means that a single gene is not sufficient, it needs other genes.
charlie wrote:
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You are also using an unconventional definition of phenotype, considering that hybrid sterility is a phenotype of hybrids,
No I'm using a conventional definition of phenotype. I explain this in my previous posts.
Charlie wrote:
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and that Darwin never dreamed of positing natural selection as the creator of phenotypes.
Yes he did. He would call them "characters".
[ 20. June 2003, 17:07: Message edited by: Nelson_Alonso ]
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Argon
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posted 20. June 2003 15:04
Thanks for the quick response. What the quote says is that we know evolution occurred in the past because we have historical evidence for it. Unfortunately, I don't think it addresses my question. I'll try once more.
What you are suggesting is that 10 million years hence, and assuming life survives, no new species or macroevolutionary changes will be seen. The reason why we can say that evolution didn't stop 10,000,004.5 years ago is because of what we saw happen afterwards. But, if you were stuck in 9,998,005.5 BC and had no idea what the future held (and this is the key point your quote does not address), why couldn't one claim that evolution had stopped then?
[ 20. June 2003, 15:14: Message edited by: Argon ]
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