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Author Topic:   random mutations
lbhandli
Inactive Member


Message 1 of 8 (208)
03-12-2001 9:25 PM


From:

Create Evolve
on 8/23/00:
quote:
Sue Cooper quoted:
"the evidence is that mutations are random in the two senses I tried to explain in my last post. ie. They are unpredictable (because they are quantum mechanical in nature and because they depend chaotically on huge numbers of variables) and the probability of a mutation is not correlated with the effect they will have on fitness."
sue continued:
"I take it you agree that mutations are unpredictable at least in practice, so we have no argument there. Do you also agree that the chance of a mutation occuring does not depend on what the effect of the mutation will be? if so this argument is indeed semantic and we can drop it now."
thmsberry: Exactly. That is why you and I no longer had an argument on this point. We are in agreement. Remember. Larry reopened discussion. I thought you and I were either done (and you had a minor issue with two of the examples I used) or we were at a stalemate and I was waiting for you to adress my main argument. However, I am glad we agree on that point.
thmsberry from 2 of Definition of Modern Synthesis
quote:
Futhermore, You do not want to do this. It would be a major point to my side. You see, it would mean that mutation do not have to be random. See horizontal mechanism result from populations of diverse live and nonliving organisms and/or there DNA interacting with an organisms Genome. This process is complex, yes. But it certainly not random. It's like will it rain or snow. Or Who will Johnny pick as a sex partner. Contingent on many variables, yes. But mutations within genomes as Biologist and Geneticist define them from an evolutionary standpoint are random, not contingent.
From post 5 by thmsberry:
quote:
Where is the respected textbook where it is defined as Random or Nonrandom.
Note--the surrounding information gave no more meaning to this question AFAICT.
quote:
Brings up the Randomness issue. But presents Randomness in terms of Randomness vs. Directed. An
argument that I have not even made.
I'm completely confused by this question as well. My question was when he said random, he meant in relation to fitness. Which all mutations are random in relation to fitness. More later.
quote:
Define in detail what you mean by ?Random in relation to fitness.? What
exactly do you mean by ?No mutation is random in a strict sense?
Given past discussions you have been involved in this should be obvious. And I'm at a loss as to why you are confused.
quote:
It has direct bearing on the discussion and what my response should be.
It is pretty clear actually, I will clarify for you. Perhaps you could enlighten us as to what exactly your confusion is.
You cited in post 2 of Definition of Modern Synthesis that (quoting again):
quote:
Futhermore, You do not want to do this. It would be a major point to my side. You see, it would mean that mutation do not have to be random. See horizontal mechanism result from populations of diverse live and nonliving organisms and/or there DNA interacting with an organisms Genome. This process is complex, yes. But it certainly not random. It's like will it rain or snow. Or Who will Johnny pick as a sex partner. Contingent on many variables, yes. But mutations within genomes as Biologist and Geneticist define them from an evolutionary standpoint are random, not contingent.
Spontaneous mutations are random in relation to fitness and random in a couple other senses:
Ayala, Francisco J. and John Kiger Jr. Modern Genetics. 1980. Benjamin/Cummings Publishing Company Inc.
pg 551
quote:
Mutations as a random process
1) Rare exceptions to the process of DNA replication
2) no way of knowing whether a given gene will mutate in a particular cell or in a particular generation...
...does not imply that no regularities exist in the mutation process."
It is not true, however, that any mutation is just as likely to occura as any other mutation.
3) Mutations are accidental, undirected, random or chance events in still another sense that is very important for evolution, namely, in the sense they are unoriented with respect to adaptation.
Lewin
quote:

...as the result of spontaneous normal cellular operations or random interactions with the environment

Of course different mutations have different causes
spontaneous mutations from Griffiths et al
pg 531
[b] [QUOTE] spontaneous are natural occurring and occur in all cells
[/b][/QUOTE]
induced:
[b] [QUOTE] Induced are porduced when an organism is exposed to a mutagenic agent or mutagen
[/b][/QUOTE]
pg 532
[b] [QUOTE] Spontaneous mutations arise from a variety of sources including errors in DNA replication, spontaneous lesions, and transposable genetic elements
[/b][/QUOTE]
Hartl and Freifelder
pg 332
[b] [QUOTE] Mutations are random events and there is no way of knowing when or in which cell a mutation will occur. However, every gene mutates at a characteristic rate making it possible to assign probabilitiesto particular mutational events. Thus, there is a definite probability that a given gene will mutate in a particular cell, and likewise a definite probability that a mutant allele of the gene will occur in a population of a particular size. Different kinds of alterations in the DNA lead to mutations, and since these changes differ substantially in complexity, they occur with quite different probabilities. Mutations are also random in the sense that their occurrence is not related to any adaptive advantage they may confer on the organism in its environment
[/b][/QUOTE]
now from you again:
quote:
Futhermore, You do not want to do this. It would be a major point to my side. You see, it would mean that mutation do not have to be random. See horizontal mechanism result from populations of diverse live and nonliving organisms and/or there DNA interacting with an organisms Genome. This process is complex, yes. But it certainly not random. It's like will it rain or snow. Or Who will Johnny pick as a sex partner. Contingent on many variables, yes. But mutations within genomes as Biologist and Geneticist define them from an evolutionary standpoint are random, not contingent.
The only important aspect of randomness to anything I'm discussing is that it is random in relation to fitness. Mutations are random in some other senses, but see the first quote at the top of this post...What did you mean by the quote directly above? How are HGTs not random in relation to fitness? Even if you don't classify them as mutations--please cite specific material that is relevant. The only challenge is if you could demonstrate that they are not random in relation to fitness. Clarify.
Thanks,
Larry Handlin
[This message has been edited by lbhandli (edited 03-13-2001).]
[This message has been edited by lbhandli (edited 03-13-2001).]

Replies to this message:
 Message 2 by Thmsberry, posted 03-13-2001 2:54 AM lbhandli has replied

lbhandli
Inactive Member


Message 3 of 8 (214)
03-13-2001 1:10 PM
Reply to: Message 2 by Thmsberry
03-13-2001 2:54 AM


[QUOTE]Originally posted by Thmsberry:
[B]
I argue that mutations are contingent or currently unpredictable by mankind.
The process by which populations of organisms adapt to their environment is extemely contingent. Mutations occur independent of any one particular environmental advantage for a given organism. This appears to be what you mean when you say random in terms of fitness. [/QUOTE]
What I mean? Yes, and what nearly every source says. It isn't that hard to follow. This is a scientific statement.
quote:
However, I believe that mutations occur because the environment changes and organism must be able to evolve to survive a continuously changing environment. Thus, I would not say that mutations are random. Mutations exists to give organisms the ability to evolve to an ever evolving environment. Thus, the fact that all life mutates is not random. Now, if you disagree with this argument, fine. But in order to disprove it, you would have to make me aware of live organisms on this planet that do not have the ability to mutate or evolve. Funny though. Because that would disprove the Theory of Evolution. A theory you have demonstrated that you agree with.
What does the above have to do with science? It appears to be personal philosophy unless you are making a Lamarkian argument. And I really don't care about your personal philosophies.
quote:
The word Random in itself is not terribly troubling. It is its association with the term Spontaneous or its implied meaning( without a planned cause). Let me explain. There is a belief that given that the environment of this planet changes and so does the life on it, the fact that these two process exist and sometimes are intertwined is a cosmic coincidence. There is no scientific evidence for this assumption. You see, I am saying that there is a purpose behind mutations and other evolutionary processes.
And how is this related to science? Your personal philosophies are quite irrelevant.
quote:
They make life adaptable to changes in populations and their environment. These individual process, however, are extremely contingent and their purpose is quite obvious at the macro. Just like it is wrong to say that evolution occurs at the individual level, it occurs at the population level. It would be horribly wrong to say that life does not change for the purpose of being able to modify itself in an environment that is constantly changing, simply because the process by which individual organisms mutate is not directed by environment and is contingent and independent of environment.
These sort of issues center around the fact that anticreationist often try to define the creator. And in their definition, The creator can’t use nature processes and contingencies in order to create.
That is nice, but I'm not interested in bad theology. Please confine you remarks to science.
quote:
If you are viewing creationism the way that I defined before,
And you still haven't explained who is counted in that definition. Is it by self-identification or by some sort of bizarre labeling based on a persons faith?
quote:
this tact is clearly a strawman. Now, if we were discussing creation science, it would not be a strawman. But we are not discussing creation science or even young earth literal biblical christian fundamentalist creationsism. So as I hope it is clear, the subtle difference behind our respective uses of the term Random has a direct bearing on a major aspect of my argument.
What argument? That you have personal faith? Okay. What does that have to do with science?
Now, let me ask you what you meant by:
quote:
Futhermore, You do not want to do this. It would be a major point to my side. You see, it would mean that mutation do not have to be random. See horizontal mechanism result from populations of diverse live and nonliving organisms and/or there DNA interacting with an organisms Genome. This process is complex, yes. But it certainly not random. It's like will it rain or snow. Or Who will Johnny pick as a sex partner. Contingent on many variables, yes. But mutations within genomes as Biologist and Geneticist define them from an evolutionary standpoint are random, not contingent.
What did this mean? It appears to be at odds with your famed consistency. Random in relation to fitness is the primary way anyone is going to address the issue so perhaps you can explain what the above was meant to convey? Or are you arguing Horizontal Gene Transfer is not random in relation to fitness? Clarify...
Cheers,
Larry Handlin

This message is a reply to:
 Message 2 by Thmsberry, posted 03-13-2001 2:54 AM Thmsberry has replied

Replies to this message:
 Message 4 by Thmsberry, posted 03-14-2001 1:00 AM lbhandli has replied

lbhandli
Inactive Member


Message 5 of 8 (224)
03-14-2001 1:36 AM
Reply to: Message 4 by Thmsberry
03-14-2001 1:00 AM


quote:
Futhermore, You do not want to do this. It would be a major point to my side. You see, it would mean that mutation do not have to be random. See horizontal mechanism result from populations of diverse live and nonliving organisms and/or there DNA interacting with an organisms Genome. This process is complex, yes. But it certainly not random. It's like will it rain or snow. Or Who will Johnny pick as a sex partner. Contingent on many variables, yes. But mutations within genomes as Biologist and Geneticist define them from an evolutionary standpoint are random,not contingent.
you from post 4:
quote:
Also, I am saying that process by which mutations occur is contingent and complex, thus making them unpredictable by mankind.
Cute. But there is no disagreement in my position.
The was the last sentence of the first quote a mistake? It directly contradicts what you say in the second quote. In the first you claim biologists and geneticists define mutations as random, not contingent. In the second, you say they are contingent and complex. If this is a mistake fine. However, I will be quoting you on how careful you are with your wording.
Additionally, I asked specifically, does this mean you are arguing HGTs are not random in relation to fitness?
Thanks,
Larry

This message is a reply to:
 Message 4 by Thmsberry, posted 03-14-2001 1:00 AM Thmsberry has replied

Replies to this message:
 Message 6 by Thmsberry, posted 03-14-2001 2:45 PM lbhandli has replied

lbhandli
Inactive Member


Message 7 of 8 (236)
03-15-2001 12:04 AM
Reply to: Message 6 by Thmsberry
03-14-2001 2:45 PM


It wasn't clear before, thank you.

This message is a reply to:
 Message 6 by Thmsberry, posted 03-14-2001 2:45 PM Thmsberry has not replied

lbhandli
Inactive Member


Message 8 of 8 (237)
03-15-2001 12:04 AM
Reply to: Message 6 by Thmsberry
03-14-2001 2:45 PM


It wasn't clear before, thank you.

This message is a reply to:
 Message 6 by Thmsberry, posted 03-14-2001 2:45 PM Thmsberry has not replied

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