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Author Topic:   About New Lamarckian Synthesis Theory
jar
Member (Idle past 393 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 16 of 264 (674649)
10-01-2012 12:14 PM


If the evironment is causing ...
If the environment was actually causing as opposed to filtering changes then the same changes should show up in all of a population living in the same environment; however evidence refutes that position.
As was pointed out in Message 57:
quote:
There is a population of mice.
The mice have baby mice.
Not all the copies are perfect, some have mutations.
Some baby mice are tan.
Some baby mice are dark gray.
Some baby mice are bright pink with yellow and green stripes.
The baby mice that are tan go out to eat and play. Those that stay on the tan rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty tan baby mice.
Those that play on the dark gray rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty tan baby mice.
The baby mice that are dark gray go out to eat and play. Those that stay on the dark gray rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty dark gray baby mice.
Those that play on the tan rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty dark gray baby mice.
The baby mice that are bright pink with yellow and green stripes go out to eat and play. They get eaten.
Soon there are two populations of mice, tan mice and dark gray mice and bad little mice are told, "If you do that again you will turn pink with yellow and green stripes and get eaten! And it will make you go blind too!".
It is a matter of filtering, not causation. The mutations continue and there will still be dark gray and tan mice born that will be filtered by the environment.

Anyone so limited that they can only spell a word one way is severely handicapped!

Replies to this message:
 Message 22 by zi ko, posted 10-02-2012 12:46 AM jar has replied

  
zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 17 of 264 (674667)
10-01-2012 2:12 PM
Reply to: Message 13 by Percy
10-01-2012 11:39 AM


Thank you Percy.I will try by my poor knowledge of biology.I think all the relevant data are well expressed in WIKIPEDIA.


This message is a reply to:
 Message 13 by Percy, posted 10-01-2012 11:39 AM Percy has seen this message but not replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 18 of 264 (674669)
10-01-2012 2:15 PM
Reply to: Message 1 by zi ko
09-28-2012 9:22 AM


Why evolutionists are not willing to discuss Lamarckian scenario in evolution?
Because it has been falsified by the evidence.
Doesn’t it show that scientists, at least in this forum, are only caring for to protect at any cost the sacred caw of exclusive random mutations?
There is nothing to protect. The evidence points to random mutations which is why we conclude that mutations are random. You, on the other hand, ignore the evidence and keep pushing guided mutations which are not supported by evidence. Why do you do that?
Epigenetic inheritance . . .
Epigenetic inheritance does not change DNA sequence nor does it explain the differences between species (e.g. the differences between humans and chimps). I really don't see how it is on topic in a discussion dealing with the question of random vs. guided mutations.
Classic evolutionists have to face this fact: ANY MUTATION DETRIMENTAL, NEUTRAL OR USEFUL IS A GUIDED BY THE ENVIRONMENT MUTATION.
Mutations are caused by mechanisms that are incapable of determining if the mutation will be harmful, neutral, or beneficial. That is why these mechanisms will produce mutations that confer antibiotic resistance when no antibiotics are present.
Surely they had ignored guided mutations, but not excluded it.
Hardly. You really need to read this paper:
http://www.genetics.org/content/28/6/491.full.pdf+html
Luria and Delbruck tested for both random and guided mutations. The results of the experiment pointed to random mutations.
"Soma to germ-line feedback
In the 1970s the immunologist Ted Steele, formerly of the University of Wollongong, and colleagues, proposed a neo-Lamarckian mechanism to try to explain why homologous DNA sequences from the VDJ gene regions of parent mice were found in their germ cells and seemed to persist in the offspring for a few generations. The mechanism involved the somatic selection and clonal amplification of newly acquired antibody gene sequences that were generated via somatic hyper-mutation in B-cells. The mRNA products of these somatically novel genes were captured by retroviruses endogenous to the B-cells and were then transported through the blood stream where they could breach the soma-germ barrier and retrofect (reverse transcribe) the newly acquired genes into the cells of the germ line." [emphasis mine]
The somatic hyper-mutation that produced those sequences were random with respect to fitness.
The effects of an animal's environment during adolescence can be passed down to future offspring, according to two new studies. If applicable to humans, the research, done on rodents, suggests that the impact of both childhood education and early abuse could span generations. The findings provide support for a 200-year-old theory of evolution that has been largely dismissed: Lamarckian evolution, which states that acquired characteristics can be passed on to offspring.
That is epigenetics. It does not involve a change in DNA sequence.

This message is a reply to:
 Message 1 by zi ko, posted 09-28-2012 9:22 AM zi ko has replied

Replies to this message:
 Message 24 by zi ko, posted 10-02-2012 2:05 AM Taq has not replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 19 of 264 (674670)
10-01-2012 2:22 PM
Reply to: Message 8 by zi ko
10-01-2012 6:52 AM


But what is the evidence for random mutations?
Beneficial mutations occur in the absence of the environment in which they are beneficial. For example, mutations conferring antibiotic and bacteriophage resistance occur in the absence of antibiotics and bacteriophage. Even more, we can study the exact mechanisms that are producing these mutations. In the following study, they measured the fit between the incoming nucleotide and polymerase responsible for extinding the DNA molecule. They found that there is a loose fit between the substrate and the enzyme resulting in the random production of mutations.
quote:
Proc Natl Acad Sci U S A. 2005 Nov 1;102(44):15803-8. Epub 2005 Oct 25.
Probing the active site tightness of DNA polymerase in subangstrom increments.
Kim TW, Delaney JC, Essigmann JM, Kool ET.
SourceDepartment of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
Abstract
We describe the use of a series of gradually expanded thymine nucleobase analogs in probing steric effects in DNA polymerase efficiency and fidelity. In these nonpolar compounds, the base size was increased incrementally over a 1.0-A range by use of variably sized atoms (H, F, Cl, Br, and I) to replace the oxygen molecules of thymine. Kinetics studies with DNA Pol I (Klenow fragment, exonuclease-deficient) in vitro showed that replication efficiency opposite adenine increased through the series, reaching a peak at the chlorinated compound. Efficiency then dropped markedly as a steric tightness limit was apparently reached. Importantly, fidelity also followed this trend, with the fidelity maximum at dichlorotoluene, the largest compound that fits without apparent repulsion. The fidelity at this point approached that of wild-type thymine. Surprisingly, the maximum fidelity and efficiency was found at a base pair size significantly larger than the natural size. Parallel bypass and mutagenesis experiments were then carried out in vivo with a bacterial assay for replication. The cellular results were virtually the same as those seen in solution. The results provide direct evidence for the importance of a tight steric fit on DNA replication fidelity. In addition, the results suggest that even high-fidelity replicative enzymes have more steric room than necessary, possibly to allow for an evolutionarily advantageous mutation rate.
Guess what gene they used to measure the mutation rate? That would be the tonB gene, the gene that was responsible for bacteriophage resistance in the Luria and Delbruck paper that I referenced above. We understand down to the angstrom why mutations are random. What do you have to show for guided mutations?
The Baldwin effect it is another argument for guided mutations and against randomness.
The Baldwin effect is selection only. It does not deal with how mutations occur. The Baldwin effect results in selection for variants that are able to learn a behavior more quickly or more effectively. The production of those variants is still reliant on random mutations.
The interesting thing is that real scientist discuss easily about diversions of evolutionary theories in contrast of participants in evolutionary forums.
Real scientists do not push ideas that are not backed by evidence, and even worse, ideas that are contradicted by evidence. They also do not confuse epigenetics and random mutagenesis as you do.
Edited by Taq, : No reason given.

This message is a reply to:
 Message 8 by zi ko, posted 10-01-2012 6:52 AM zi ko has not replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 20 of 264 (674678)
10-01-2012 2:46 PM
Reply to: Message 13 by Percy
10-01-2012 11:39 AM


I think the way Zi Ko is looking at this is that if a behavior can be considered an acquired characteristic, then if that behavior is heritable it could be considered Lamarckian because it would be a heritable acquired characteristic, and it could be considered guided by the environment because the environment could have trained in the behavior, either naturally in the wild or experimentally through laboratory training, or through a classroom, and just through normal day-to-day activities.
Well, fair enough. However, it is not the specific mutation that is guided, and that's what zi ko is getting wrong.
One could say that there is guidance toward mutations that support the particular behavior, and fair enough on that, too. The tradition view would be to call that filtering by natural selection, rather than guidance. If zi ko is trying to make a case against the Darwinian account, then he needs to do better than that.

Jesus was a liberal hippie

This message is a reply to:
 Message 13 by Percy, posted 10-01-2012 11:39 AM Percy has seen this message but not replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 21 of 264 (674681)
10-01-2012 2:50 PM
Reply to: Message 12 by zi ko
10-01-2012 11:27 AM


nwr writes:
No, it isn't.
zi ko writes:
Can you or anny body else prove this assertion?
What's to prove?
The Baldwin effect is fully accounted for by standard Darwinian theory, as explained in the Wikipedia page that I linked to.

Jesus was a liberal hippie

This message is a reply to:
 Message 12 by zi ko, posted 10-01-2012 11:27 AM zi ko has replied

Replies to this message:
 Message 25 by zi ko, posted 10-02-2012 3:24 AM nwr has replied

  
zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 22 of 264 (674707)
10-02-2012 12:46 AM
Reply to: Message 16 by jar
10-01-2012 12:14 PM


Re: If the evironment is causing ...
Not all the copies are perfect, some have mutations.
I agree with the rest. But what would you say if add: ... mutations that are guided by environment? How can you exclude this scenario? Just by saying that 'all scientists believe so'? You must have evidence for it to say so.
If the environment was actually causing as opposed to filtering changes then the same changes should show up in all of a population living in the same environment; however evidence refutes that position.
Environment is never the same for different members.


This message is a reply to:
 Message 16 by jar, posted 10-01-2012 12:14 PM jar has replied

Replies to this message:
 Message 27 by jar, posted 10-02-2012 9:59 AM zi ko has replied

  
Dr Jack
Member
Posts: 3514
From: Immigrant in the land of Deutsch
Joined: 07-14-2003
Member Rating: 8.7


Message 23 of 264 (674710)
10-02-2012 1:41 AM
Reply to: Message 1 by zi ko
09-28-2012 9:22 AM


Epigenetics is not Lamarckian
Epigenetics is not Lamarckian. It shares some small piece in common but it does not allow Lamarck's method of change. There are two fundamental reasons for this:
1. Epigenetic change is not accretional. Epigenetic switches are there or not based on genetic sequences, changing epigenetic state does not create new opportunities for new epigenetic changes. This means that epigenetic change can only alter an organism's phenotype within finite limits.
2. There's a major part of Lamarck's ideas that tends to be forgotten. Lamarck believed in a kind of "chain of being" where new organisms rose up the chain in a largely linear fashion, so that "primitive" organisms such as, say, a leech were not evolved for a niche but simply less advanced along a chain of being that we had long since crossed. Obviously, epigenetics provides no support for this notion.

This message is a reply to:
 Message 1 by zi ko, posted 09-28-2012 9:22 AM zi ko has replied

Replies to this message:
 Message 26 by zi ko, posted 10-02-2012 4:01 AM Dr Jack has replied

  
zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 24 of 264 (674711)
10-02-2012 2:05 AM
Reply to: Message 18 by Taq
10-01-2012 2:15 PM


Epigenetic inheritance does not change DNA sequence nor does it explain the differences between species (e.g. the differences between humans and chimps). I really don't see how it is on topic in a discussion dealing with the question of random vs. guided mutations.
Epigenetic inheritance gives the first part of a mechanism of environmental effect on outer and some times deep genome. It paves the way for deep genome mutatations relevant to organism's needs. Of course nobody would expect to see such mutations in action.
Mutations are caused by mechanisms that are incapable of determining if the mutation will be harmful, neutral, or beneficial. That is why these mechanisms will produce mutations that confer antibiotic resistance when no antibiotics are present.
I almost agree.But environment knows about which mutations will be needed even for the near future in a range of propailities.
Why do you do that?
Because you ignore a possible scenario of evolution in spite of very little evidence against it.
Luria and Delbruck tested for both random and guided mutations. The results of the experiment pointed to random mutations.
This experiment refers to one cell organisms, where randomess is an economical mechanism for nature to choose. You should bring evidences from multicellular organisms.
The somatic hyper-mutation that produced those sequences were random with respect to fitness.
If you go a bit earlier you will see that environment had caused hyper mutation, at the time it needed it.
That is epigenetics. It does not involve a change in DNA sequence
You could see that change if you had time.
Edited by zi ko, : No reason given.


This message is a reply to:
 Message 18 by Taq, posted 10-01-2012 2:15 PM Taq has not replied

  
zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 25 of 264 (674713)
10-02-2012 3:24 AM
Reply to: Message 21 by nwr
10-01-2012 2:50 PM


The "Baldwin effect" is better understood in evo-devo (evolutionary developmental biology) literature as a scenario in which a character or trait change occurring in an organism as a result of its interaction with its environment becomes gradually assimilated into its developmental genetic or epigenetic repertoire (Simpson, 1953; Newman, 2002). In the words of Daniel Dennett,
Thanks to the Baldwin effect, species can be said to pretest the efficacy of particular different designs by phenotypic (individual) exploration of the space of nearby possibilities. If a particularly winning setting is thereby discovered, this discovery will create a new selection pressure: organisms that are closer in the adaptive landscape to that discovery will have a clear advantage over those more distant. (p. 69,[1] quoting Dennett, 1991).....According to Dennett, recent work has rendered the Baldwin effect "no longer a controversial wrinkle in orthodox Darwinism" (p. 69[1]).
From above we can deduct that 1. Environmental information can result deep genome changes. 2. The Selection mechanism is present.3. There was for some time a wrinkle in orthodox Darvinism. what is the new evidence that the wrinkle has gone or this not just a belief? Where is the proof that relevant mutations were not guided?


This message is a reply to:
 Message 21 by nwr, posted 10-01-2012 2:50 PM nwr has replied

Replies to this message:
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zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 26 of 264 (674714)
10-02-2012 4:01 AM
Reply to: Message 23 by Dr Jack
10-02-2012 1:41 AM


Re: Epigenetics is not Lamarckian
1. Epigenetic change is not accretional. Epigenetic switches are there or not based on genetic sequences, changing epigenetic state does not create new opportunities for new epigenetic changes. This means that epigenetic change can only alter an organism's phenotype within finite limits.
Epigenetic changes pave the way to relevant epig. changes.
2. There's a major part of Lamarck's ideas that tends to be forgotten. Lamarck believed in a kind of "chain of being" where new organisms rose up the chain in a largely linear fashion, so that "primitive" organisms such as, say, a leech were not evolved for a niche but simply less advanced along a chain of being that we had long since crossed. Obviously, epigenetics provides no support for this notion.
That is why i am talking about the NEW SYNTHESIS OF LAMARCKISM.


This message is a reply to:
 Message 23 by Dr Jack, posted 10-02-2012 1:41 AM Dr Jack has replied

Replies to this message:
 Message 34 by Dr Jack, posted 10-03-2012 4:21 AM zi ko has replied

  
jar
Member (Idle past 393 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 27 of 264 (674724)
10-02-2012 9:59 AM
Reply to: Message 22 by zi ko
10-02-2012 12:46 AM


Re: If the evironment is causing ...
jar writes:
Not all the copies are perfect, some have mutations.
I agree with the rest. But what would you say if add: ... mutations that are guided by environment? How can you exclude this scenario? Just by saying that 'all scientists believe so'? You must have evidence for it to say so.
If you said that I would laugh, laugh loudly and heartily. And I presented the evidence and and you even quoted part of my evidence. But did you actually read it?
If the environment was actually causing as opposed to filtering changes then the same changes should show up in all of a population living in the same environment; however evidence refutes that position.
Environment is never the same for different members.
Nonsense, utter nonsense.
Let me repeat the example for you.
quote:
There is a population of mice.
The mice have baby mice.
Not all the copies are perfect, some have mutations.
Some baby mice are tan.
Some baby mice are dark gray.
Some baby mice are bright pink with yellow and green stripes.
The baby mice that are tan go out to eat and play. Those that stay on the tan rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty tan baby mice.
Those that play on the dark gray rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty tan baby mice.
The baby mice that are dark gray go out to eat and play. Those that stay on the dark gray rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty dark gray baby mice.
Those that play on the tan rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty dark gray baby mice.
The baby mice that are bright pink with yellow and green stripes go out to eat and play. They get eaten.
Soon there are two populations of mice, tan mice and dark gray mice and bad little mice are told, "If you do that again you will turn pink with yellow and green stripes and get eaten! And it will make you go blind too!".
The environment did absolutely nothing to cause the mutations.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 22 by zi ko, posted 10-02-2012 12:46 AM zi ko has replied

Replies to this message:
 Message 28 by zi ko, posted 10-02-2012 10:45 AM jar has replied

  
zi ko
Member (Idle past 3619 days)
Posts: 578
Joined: 01-18-2011


Message 28 of 264 (674726)
10-02-2012 10:45 AM
Reply to: Message 27 by jar
10-02-2012 9:59 AM


BRe: If the evironment is causing ...
Before you start laughing i suggest you to make some thinking firstly.Serious scientists have different wiews than you on the matter.(See O.P) I would be most grateful to you if you could give me some evidences concerning your stiff belief on random mutations, so to restore my own shattered belief on it.


This message is a reply to:
 Message 27 by jar, posted 10-02-2012 9:59 AM jar has replied

Replies to this message:
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 Message 30 by jar, posted 10-02-2012 10:55 AM zi ko has not replied

  
NoNukes
Inactive Member


Message 29 of 264 (674728)
10-02-2012 10:54 AM
Reply to: Message 28 by zi ko
10-02-2012 10:45 AM


Re: BRe: If the evironment is causing ...
I would be most grateful to you if you could give me some evidences concerning your stiff belief on random mutations.
It is fair to note that jar did not provide any evidence supporting the fact that mutations are random with respect to fitness. But that scarcely matters, because others have done so, and you've ignored what they have presented.
As for the OP, it does leave room open to argue about some Lamarckian aspects to epigenesis, but even that modification might well be random with respect to fitness even if the mutations themselves are induced by external stimuli. In order to have a case, you need to show not just that the rate of mutations is susceptible to environmental pressure, but that the fitness of those mutations is also susceptible to the same pressure.

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The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.
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This message is a reply to:
 Message 28 by zi ko, posted 10-02-2012 10:45 AM zi ko has not replied

  
jar
Member (Idle past 393 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 30 of 264 (674729)
10-02-2012 10:55 AM
Reply to: Message 28 by zi ko
10-02-2012 10:45 AM


Re: BRe: If the evironment is causing ...
I did provide evidence just above but will happily repeat it yet again.
quote:
There is a population of mice.
The mice have baby mice.
Not all the copies are perfect, some have mutations.
Some baby mice are tan.
Some baby mice are dark gray.
Some baby mice are bright pink with yellow and green stripes.
The baby mice that are tan go out to eat and play. Those that stay on the tan rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty tan baby mice.
Those that play on the dark gray rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty tan baby mice.
The baby mice that are dark gray go out to eat and play. Those that stay on the dark gray rocks find lots of food and have fun playing. They grow up and marry the mouse next door and have lots of pretty dark gray baby mice.
Those that play on the tan rock though get eaten by predators and don't get to play or have fun or grow up to marry the mouse next door and have lots of pretty dark gray baby mice.
The baby mice that are bright pink with yellow and green stripes go out to eat and play. They get eaten.
Soon there are two populations of mice, tan mice and dark gray mice and bad little mice are told, "If you do that again you will turn pink with yellow and green stripes and get eaten! And it will make you go blind too!".
Mice had baby meeces that were both tan and dark gray in the same litter.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 28 by zi ko, posted 10-02-2012 10:45 AM zi ko has not replied

  
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