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Author Topic:   New theory about evolution between creationism and evolution.
zi ko
Member (Idle past 3620 days)
Posts: 578
Joined: 01-18-2011


Message 361 of 433 (655266)
03-08-2012 10:41 PM
Reply to: Message 357 by Wounded King
03-08-2012 4:49 AM


Re: Are there RANDOM MUTATIONS?
It seems strange then that absolutely none of the evidence presented in favour of an actual mechanism for guided mutations seems to have been in the metazoa. The only putative mechanisms that been put forward, i.e. Wright's de-repression based system, only seem to work in the context of unicellular organisms and have no readily apparent way to apply to multicellular organisms where there is a separation of the germ line from the somatic cells.
This does not mean that such mechanisms don't exist.Neural intervention in evolution is a very new idea, so it is not logical to expect presently relative evidence of such mechanisms.
And welcome back to evolutionary genetics 101! This is absolutely basic stuff Zi Ko, and if you aren't familiar with it then you just don't understand evolutionary theory at all.
The simple answer is that the disparities are principally the result of natural selection.
I don't deny natural selection's role in evolution. It is randomness's in mutations predictive value that concerns me.
Edited by zi ko, : No reason given.

This message is a reply to:
 Message 357 by Wounded King, posted 03-08-2012 4:49 AM Wounded King has replied

Replies to this message:
 Message 362 by Wounded King, posted 03-09-2012 4:27 AM zi ko has replied
 Message 364 by Taq, posted 03-09-2012 12:11 PM zi ko has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 362 of 433 (655281)
03-09-2012 4:27 AM
Reply to: Message 361 by zi ko
03-08-2012 10:41 PM


Re: Are there RANDOM MUTATIONS?
This does not mean that such mechanisms don't exist.
Sure and it doesn't mean that magical faeries aren't directing evolution, but at the moment your neural hypothesis and the magical faery hypothesis have the same evidentiary footing.
Neural intervention in evolution is a very new idea, so it is not logical to expect presently relative evidence of such mechanisms.
Except we would expect some evidence because even if the idea is new the mechanism shouldn't be, this should be a mechanism that has operated for millions of years. So far there hasn't been any evidence presented for directed mutation in the metazoa. So not only is there no evidence of a mechanism there is no data which requires such a mechanism to explain it.
If all you have is a theory which is mechanically indistinguishable from current theories based on random mutation and has no coherent and tenable mechanism then you have nothing that anyone should care two hoots about.
I don't deny natural selection's role in evolution.
Maybe you don't deny it but when you ask why there are differences in the divergences of different genes between chimps and humans then you make it very clear that you ignore it, meaning that you are ignoring one of the central features of evolutionary theory.
It is randomness's in mutations predictive value that concerns me.
This seems incoherent to me. Why should random mutations themselves have a predictive value? Why should it concern you?
Random mutations occur, they generated functional diversity and natural selection acts upon that functional diversity so as to over time shape the genomes of a population.
We can measure the rates and nature of these mutations and learn things about their probabilistic distribution. For a large enough population this may allow us to make certain predictions, such as in bacterial experiments where we can have a good idea of the size and number of generations required to have a diverse enough population that almost every single step nucleotide mutation will have probably occurred.
TTFN,
WK

This message is a reply to:
 Message 361 by zi ko, posted 03-08-2012 10:41 PM zi ko has replied

Replies to this message:
 Message 365 by zi ko, posted 03-09-2012 11:19 PM Wounded King has not replied

  
Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 363 of 433 (655319)
03-09-2012 12:06 PM
Reply to: Message 360 by zi ko
03-08-2012 10:18 PM


Re: Are there ONLY RANDOM MUTATIONS?
but what is the evidence that these supposed random mutageneses are not in fact guided from environment,external or internal?
This goes back to the two foundational papers on mutations:
Luria and Delbruck Flucutaiton Experiment
Lederbergs' Plate Replica Experiment
In these experiments they demonstrate that mutations confering bacteriophage and antibiotic resistance occur in the absence of either bacteriophage or antibiotics. In other words, the mutations occur when they are not needed. The occur spontaneously and without any meaningful input from fitness. They are OBSERVED to be random with respect to fitness.
So why would a guided process produce mutations that are not needed, and in fact deleterious to the health of the organism? That is the opposite of what a guided process should look like, and yet that is the process of mutagenesis that we observe. The very same mechanisms that produce beneficial mutations also produce neutral and detrimental mutations. There is no way around this conclusion.
Again, what is the evidence for random mutations vs guided mutations?
I have provided evidence that they are random. It is now up to you to supply evidence that mutations are guided, or retract your claim that they are guided.
I am afraid also current theory has the same problem at least up to now and it had a lot of time to prove itself.
It doesn't have this problem, and hasn't since the 1940's and 1950's when those experiments above were done. Scientists had demonstrated that mutations were random with respect to fitness before they had even discovered DNA. Since the discovery of DNA we have been able to tease out the specific molecular mechanisms of mutagenesis, and once again they have been found to be random with respect to fitness (such as in the case of the Wright et al. paper that we discussed).
Maybe i have to stress again "guidance" in my hypothesis is "collecting" information from environment.
How is this done? What are the molecular mechanisms that are involved? How does one design and experiment to test this hypothesis?

This message is a reply to:
 Message 360 by zi ko, posted 03-08-2012 10:18 PM zi ko has replied

Replies to this message:
 Message 367 by zi ko, posted 03-10-2012 2:56 AM Taq has replied

  
Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 364 of 433 (655321)
03-09-2012 12:11 PM
Reply to: Message 361 by zi ko
03-08-2012 10:41 PM


Re: Are there RANDOM MUTATIONS?
This does not mean that such mechanisms don't exist.
But you are saying that they DO exist, so it is up to you to supply evidence for this claim or retract it until you do have this evidence.
Neural intervention in evolution is a very new idea
From everything I have seen you post, it is an entirely made up idea. It is make believe.
It is randomness's in mutations predictive value that concerns me.
Then you should read the Luria and Delbruck paper where one of their hypotheses predicted that there would be high variance in the number of bacteriophage mutants in parallel cultures due to random mutations. This work was done in the 1940's, and it has the very predictions you claim don't exist. You are 70 years behind modern science.

This message is a reply to:
 Message 361 by zi ko, posted 03-08-2012 10:41 PM zi ko has not replied

  
zi ko
Member (Idle past 3620 days)
Posts: 578
Joined: 01-18-2011


Message 365 of 433 (655392)
03-09-2012 11:19 PM
Reply to: Message 362 by Wounded King
03-09-2012 4:27 AM


Re: Are there RANDOM MUTATIONS?
but when you ask why there are differences in the divergences of different genes between chimps and humans then you make it very clear that you ignore it, meaning that you are ignoring one of the central features of evolutionary theory.
As i had told you again. i just wanted face Taq's assertiion that guided mutations have no predictive value as compared with random mutations. He understood my remark and answered about it properly.
Why should random mutations themselves have a predictive value? Why should it concern you?
Don't you think this would help random mutations concept to be more easily accepted by reasonable people? This is the core of my argumentation on this thread.
Random mutations occur, they generated functional diversity and natural selection acts upon that functional diversity so as to over time shape the genomes of a population
With the same justification, somebody could say exactly the same about guided ,through environment -organism direct interaction, mutations with the same inpact on divercification and genomes through natural selection.
Why does he have to choose one over the other?

This message is a reply to:
 Message 362 by Wounded King, posted 03-09-2012 4:27 AM Wounded King has not replied

  
subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 366 of 433 (655393)
03-10-2012 12:14 AM
Reply to: Message 360 by zi ko
03-08-2012 10:18 PM


Re: Are there ONLY RANDOM MUTATIONS?
I can't pretend i fully understand this ERV stuff and its predictive value as regards randomness in mutations.In any case this complex example show the difficulty of the theory to give other more easily understandable examples. but what is the evidence that these supposed random mutageneses are not in fact guided from environment,external or internal? So we are back to the same basic issue:choosing between random or not random mutations is a matter of belief.
So you admit you don't understand the science yet you feel qualified to comment on the validity of it versus some other hypothesis.
Hubris much?

Ridicule is the only weapon which can be used against unintelligible propositions. -- Thomas Jefferson
We see monsters where science shows us windmills. -- Phat
It has always struck me as odd that fundies devote so much time and effort into trying to find a naturalistic explanation for their mythical flood, while looking for magical explanations for things that actually happened. -- Dr. Adequate
...creationists have a great way to detect fraud and it doesn't take 8 or 40 years or even a scientific degree to spot the fraud--'if it disagrees with the bible then it is wrong'.... -- archaeologist

This message is a reply to:
 Message 360 by zi ko, posted 03-08-2012 10:18 PM zi ko has not replied

  
zi ko
Member (Idle past 3620 days)
Posts: 578
Joined: 01-18-2011


Message 367 of 433 (655412)
03-10-2012 2:56 AM
Reply to: Message 363 by Taq
03-09-2012 12:06 PM


Re: Are there ONLY RANDOM MUTATIONS?
Luria and Delbruck Flucutaiton Experiment
Lederbergs' Plate Replica Experiment
These are just experiments ( very important of course) and as such have not any predictive value.
Any way you treat their results in the way they fit to your expectations and beliefs. I see them quite differently:
1.You can't apply them easily to metazoa, where things are much complicated and where nature life cannot rely it's preservation on pure chance. Now environmental information must be used to prevent the disorginizing effect of the expected more common deleterious mutations, through reducing their rates.
2.In one cell organisms nature can use more easily "randomness" in mutations for it's final goal, e.g ,life's preservation. So we can't really talk about real randomness.
How is this done? What are the molecular mechanisms that are involved? How does one design and experiment to test this hypothesis?
I n metazoa ,through neural system.With the same mechanism which informs and causes span life expectation reduction on descendants of ancestors that had suffered a famin some generations ago.( a Swedish study)
Edited by zi ko, : No reason given.
Edited by zi ko, : No reason given.

This message is a reply to:
 Message 363 by Taq, posted 03-09-2012 12:06 PM Taq has replied

Replies to this message:
 Message 370 by Taq, posted 03-12-2012 1:29 PM zi ko has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 368 of 433 (655636)
03-12-2012 9:21 AM


Zi Ko's new best friend?
I came across a paper recently and I find it hard to believe that it isn't one Zi Ko has brought to our attention. The paper is 'Neural Control of Gene Recruitment in Metazoans' by Nelson Cabej (2011) who also has a website http://www.epigeneticscomesofage.com .
It seems that Zi Ko and Dr. Cabej may be long lost soul mates.
Nelson Cabej writes:
The second possibility of the cause of gene recruitment is that metazoans are endowed with capability for recruiting genes, for producing adaptive morphological, physiological, life history, and behavioral changes in response to the changing environment. It would essentially require an inherent potential of the organism to determine the spatial (where) and temporal (when) expression of its genes, suggesting manipulation of gene expression.
...
While the above, and numerous similar examples, represent no authentic cases of gene recruitment they demonstrate the ability of the central nervous system to manipulate expression of genes, i.e. to adaptively express specific genes in response to specific stimuli by nonclassical genetic mechanisms. This is made possible by the capability of the central nervous system to interpret and explicate to non-nervous cells the meaning of the stimulus in the language of gene. Thus, the central nervous system (CNS) is capable of establishing new, previously nonexisting, causal relationships between various stimuli and practically any gene.
...
We might never be able to directly demonstrate how gene recruitment took place in any particular case in the course of metazoan evolution, but the representative evidence presented in this article represents weighty premises for a general inference on the nature and origin of the gene recruitment.
When we remember:
1 That the central nervous system is responsible for gene recruitments that bring about inherited phenotypic changes in cases of transgenerational developmental plasticity;
2 That the CNS is uniquely involved in the regulation of developmental pathways for changed/new characters in the examples presented in this article and numerous others;
3 That the developmental pathways leading to the appearance of changed/new characters start with chemical signals from the central nervous system;
4 That the failure of the CNS to produce the signal that triggers the relevant developmental pathway prevents the development of the new/changed character, although all the genes of the pathway are present and functional.
When all the above facts are taken into consideration, one cannot help but think that the central nervous system has been crucially involved in gene recruitment throughout metazoan evolution.
Despite Cabej's emphasis on the CNS' role in the 'processing of information' most of his examples are developmental and are more related to the CNS' development and how that interacts with other developing systems than to the nervous system's role as a mediator of environmental information, and certainly not the direct result of neural activity.
TTFN,
WK

Replies to this message:
 Message 369 by zi ko, posted 03-12-2012 12:25 PM Wounded King has not replied
 Message 371 by Taq, posted 03-12-2012 1:32 PM Wounded King has not replied

  
zi ko
Member (Idle past 3620 days)
Posts: 578
Joined: 01-18-2011


Message 369 of 433 (655650)
03-12-2012 12:25 PM
Reply to: Message 368 by Wounded King
03-12-2012 9:21 AM


Re: Zi Ko's new best friend?
I came across a paper recently and I find it hard to believe that it isn't one Zi Ko has brought to our attention. The paper is 'Neural Control of Gene Recruitment in Metazoans' by Nelson Cabej (2011) who also has a website http://www.epigeneticscomesofage.com .
It seems that Zi Ko and Dr. Cabej may be long lost soul mates.
Very interesting. I never knew anything about Dr Cabej or his work. Thank you any way.

This message is a reply to:
 Message 368 by Wounded King, posted 03-12-2012 9:21 AM Wounded King has not replied

  
Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 370 of 433 (655653)
03-12-2012 1:29 PM
Reply to: Message 367 by zi ko
03-10-2012 2:56 AM


Re: Are there ONLY RANDOM MUTATIONS?
These are just experiments ( very important of course) and as such have not any predictive value.
The hypotheses that the papers tested through those experiments did have predictive value. Please read the Luria and Delbruck paper. They spell out numerous hypotheses that they test with those experiments, one of which is random mutagenesis.
Any way you treat their results in the way they fit to your expectations and beliefs.
No, I treat them as they should be treated. Please read the Luria and Delbruck paper. It spells out what the results should be if the mutations are guided and what the results should look like if the mutations are random. Please show why their hypotheses are wrong, if you can.
1.You can't apply them easily to metazoa, where things are much complicated and where nature life cannot rely it's preservation on pure chance. Now environmental information must be used to prevent the disorginizing effect of the expected more common deleterious mutations, through reducing their rates.
How does the rate reducing mechanism know which mutations to fix and which to not fix?
2.In one cell organisms nature can use more easily "randomness" in mutations for it's final goal, e.g ,life's preservation. So we can't really talk about real randomness.
But we can talk about the fact that the same mechanisms that produce beneficial mutations also produce neutral and detrimental mutations which is contrary to the hypothesis of guided mutations.
I n metazoa ,through neural system.
That is not a mechanism. That is make believe. A mechanism has evidence to back it up.

This message is a reply to:
 Message 367 by zi ko, posted 03-10-2012 2:56 AM zi ko has replied

Replies to this message:
 Message 372 by zi ko, posted 03-13-2012 12:36 PM Taq has not replied

  
Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 371 of 433 (655654)
03-12-2012 1:32 PM
Reply to: Message 368 by Wounded King
03-12-2012 9:21 AM


Re: Zi Ko's new best friend?
Despite Cabej's emphasis on the CNS' role in the 'processing of information' most of his examples are developmental and are more related to the CNS' development and how that interacts with other developing systems than to the nervous system's role as a mediator of environmental information, and certainly not the direct result of neural activity.
It also deals with gene regulation, not DNA sequence. Zi ko is trying to say that the brain can change DNA sequence which is quite different than gene regulation.

This message is a reply to:
 Message 368 by Wounded King, posted 03-12-2012 9:21 AM Wounded King has not replied

  
zi ko
Member (Idle past 3620 days)
Posts: 578
Joined: 01-18-2011


Message 372 of 433 (655767)
03-13-2012 12:36 PM
Reply to: Message 370 by Taq
03-12-2012 1:29 PM


Re: Are there ONLY RANDOM MUTATIONS?
The hypotheses that the papers tested through those experiments did have predictive value. Please read the Luria and Delbruck paper. They spell out numerous hypotheses that they test with those experiments, one of which is random mutagenesis.
OK , the experiment proves the existance of random mutations. But:
1.It does not preclude guided mutations in bacteria , as it didn't take on account the time factor of the stress, the type of the stimuli ,ect, and more so in metazoa.
2.Cairns and many others have proved and as it is generally now accepted, that bacteria in stress (i.e lack of glucose) cause increased rate of mutation (beneficial or or non). This fact makes in this case, guided mutations unnecessary. In more complicated organisms this randomess could be lethal l for the species. Randomness and non randomess are serving the same purpose; preseving life. So there isn't real randomness.
How does the rate reducing mechanism know which mutations to fix and which to not fix?
It rests on the needs of the organism.
But we can talk about the fact that the same mechanisms that produce beneficial mutations also produce neutral and detrimental mutations which is contrary to the hypothesis of guided mutations.
It is not contrary. We don't need to confine guided mutations to only beneficial mutations, but as a boad canalisation to a direction, that is relevant to the needs. Randomness still plays a role ( the continuation principal).
I n metazoa ,through neural system.
That is not a mechanism. That is make believe. A mechanism has evidence to back it up.
See W.K's 368 post.
Edited by zi ko, : No reason given.

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 Message 370 by Taq, posted 03-12-2012 1:29 PM Taq has not replied

Replies to this message:
 Message 373 by Wounded King, posted 03-13-2012 1:45 PM zi ko has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 373 of 433 (655777)
03-13-2012 1:45 PM
Reply to: Message 372 by zi ko
03-13-2012 12:36 PM


Re: Are there ONLY RANDOM MUTATIONS?
That paper is also pretty light on the evidence, as the author himself states ...
Cabej writes:
While the above, and numerous similar examples, represent no authentic cases of gene recruitment
He has an idea and because the nervous system is an important factor during metazoan development and acts as an organising center for various other systems he thinks it should be able to do what he proposes. But there is not any solid evidence of it and all the examples he gives really come down to standard evolution acting upon developmental systems that just happen to involve the CNS as part of their development.
As Taq pointed out the paper doesn't propose the sort of directed genetic changes you have been proposing. Instead it is a more like some of Waddington's epigenetic scenarios where the CNS interaction with the environment tends to channel selection in a particular direction through changes in gene expression patterns controlled or initiated by the CNS.
TTFN,
WK

This message is a reply to:
 Message 372 by zi ko, posted 03-13-2012 12:36 PM zi ko has not replied

Replies to this message:
 Message 374 by AceGreen, posted 03-14-2012 10:45 AM Wounded King has replied

  
AceGreen
Junior Member (Idle past 4397 days)
Posts: 2
Joined: 03-14-2012


Message 374 of 433 (655879)
03-14-2012 10:45 AM
Reply to: Message 373 by Wounded King
03-13-2012 1:45 PM


Re: Are there ONLY RANDOM MUTATIONS?
I think it would be profitable for both zi ko and Wounded King to read his book Epigenetic Principles of Evolution. It seems to me that examples of direct involvement of the CNS in evolution are mentioned. I don’t think he believes the CNS can induce changes in DNA base sequences. I haven’t read his article but the book basically rejects the opinion that there is not any solid evidence of it and all the examples he gives really come down to standard evolution acting upon developmental systems that just happen to involve the CNS as part of their development. In his website I read that Eva Jablonka, a leading biologist, writes that the book provides a host of useful examples arguing convincingly that the nervous system has a central role in animal evolution.

This message is a reply to:
 Message 373 by Wounded King, posted 03-13-2012 1:45 PM Wounded King has replied

Replies to this message:
 Message 375 by Wounded King, posted 03-14-2012 12:23 PM AceGreen has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 375 of 433 (655895)
03-14-2012 12:23 PM
Reply to: Message 374 by AceGreen
03-14-2012 10:45 AM


Re: Are there ONLY RANDOM MUTATIONS?
Sure Ace, you stump up the ~$150 dollars that Cabej's book costs and I'll be happy to read it.
It seems to me that examples of direct involvement of the CNS in evolution are mentioned.
This is pretty vague, I'm quite happy to stipulate that the CNS has direct involvement in evolution in many ways represented in the examples in the paper, I just don't think that there is much evidence for the more speculative way Cabej describes in his paper. Cabej himself states that his examples of genee recruitment are not examples of a neural mechanism of gene recruitment but simply of gene recruitment in which the nervous system was involved. In at least 2 of the examples, Pax6 and Neural Crest Cells I'd say it was the role of the developing nervous system as an organising centre that was the cause of that involvement since the key developmental timepoints involved are well before the CNS starts acting as a central interpreter of environmental information.
Even in the introduction he only cites his book as a reference for examples of metazoans directly controlling their own gene expression instead of actually giving any examples or details, so it is hard to know exactly what sort of thing he is thinking of. There are plenty of environmental stimuli that change gene expression, some of these are mediated through the nervous system, what Cabej seems to be proposing is a more complex phenomenon than simply that observation and the fact it is a suitable substrate for heritable variation and natural selection surely?
I don’t think he believes the CNS can induce changes in DNA base sequences.
I don't think he does either, in fact that was pretty much exactly what I said in the last paragraph of the post you were replying too.
I doubt that Zi Ko considers that Cabej's thesis either, that is more what Zi Ko's own theory is about.
TTFN,
WK

This message is a reply to:
 Message 374 by AceGreen, posted 03-14-2012 10:45 AM AceGreen has replied

Replies to this message:
 Message 376 by AceGreen, posted 03-14-2012 8:58 PM Wounded King has not replied

  
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