Re: Dawkins gives incorrect answer

From: Guy Hoelzer (hoelzer_at_unr.edu)
Date: 08/21/04 

Date: Sat, 21 Aug 2004 16:42:09 +0000 (UTC)

Michael,

in article cg3dgp$lng$1@darwin.ediacara.org, Michael Ragland at
ragland37@webtv.net wrote on 8/19/04 4:35 PM:

[snip]

> MR:
> Let me explain my position. Natural selection not only filters out
> dissonant information but it selects mutations which are favorable to
> species being able to survive and reproduce.

GH:
I think this is actually only one thing that natural selection is doing.
There is no mechanistic difference I can see between filtering out the bad
and selecting the good.

> I already stated, "However, it was my point (perhaps erroneous) that
> according to Shannon's information model mutations represented the prior
> unknown or that wider field of possibilities which natural selection
> tailored down to probable possibilities and finally that which helped
> the organism survive and reproduce." You stated you basically agreed
> with my parse commentary. You wrote, "I would also agree with Tim that
> the typically strong effect of natural selection in decreasing genetic
> variation limits the extent of information that can be structurally
> configured in the gene pool." I responded, "Yes but it also favors
> those qualities which have been selected by natural selection for
> organisms to optimally survive and reproduce." You declare, "I've said
> as much myself on sbe, and I don't see how this contradicts anything I
> wrote." Mr. Hoelzer if natural selection favors qualities which have
> been naturally selected for organisms to optimally survive and reproduce
> then this information isn't going to just sit stagnant in gene pools but
> being genetically transmitted across generations. In other words one of
> the functions of natural selection is to add information to gene pools.
> Is this exactly the same as inheritance. No, its not. The point,
> however, is natural selection and inheritance are interrelated and
> qualities which have been naturally selected for organisms to optimally
> survive and reproduce are going to be genetically transmitted across
> generations. Let me give an example. In our evolutionary past aggression
> was selected by natural selection and imprinted on our DNA and it was
> necessary for survival and reproduction. Irrespective of inheritance,
> genetic variation, etc. every human being born possesses this trait of
> aggression. It was naturally selected and through inheritance this
> genetic information has been transmitted generation after generation
> after generation irrespective of geography, language, etc.

GH:
OK, although I strongly doubt that geography and language had no influence
on the evolution of human aggression.
 
> MR:
> As I commented to Mr. Tyler mutations are not like rain showers and
> human DNA has basically remained the same as it was ten thousand years
> ago.
>
> GH:
> Evidence? I suspect that this is a guess on your part, and that experts
> would either agree or disagree based upon their sensitivity to degree of
> divergence. Some, maybe you, would say that a 1% sequence divergence
> between the old and extant population can be described as "basically
> remained the same." Of course, some instances of the difference between
> species involves less divergence than this. Consider the recent
> literature on "speciation genes."
>
> MR:
> It isn't a guess as what I read what someone else had said. Here's a
> brief article showing the similarity of Cro-Magnon mtDNA to modern DNA.
> Interestingly, the similariries and differrences between ancient and
> modern human DNA are tied up with the arguments from the "out-of-Africa"
> school and the multi-regional school of our origins.

GH:
This has been the major basis of the debate between these two schools of
though ever since the original mitochondrial Eve paper. Before that the
debate was just a squabble among a few physical anthropologists.
 
[snip]

> Cro-Magnon sequences fall within a genetic category shared by people
> today but not by Neandertals, the scientists report. This result aligns
> with the theory that modern H. sapiens originated in Africa around
> 150,000 years ago and then replaced Neandertals in Europe rather than
> interbred with them, Bertorelle and his coworkers say.

GH:
Most measures of the genetic similarity between gene pools take into account
the amount of shared variation. Humans share at least some of their
variation with almost any other species you can mention, so of course they
share plenty with Cro-Magnon's and Neanderthals. And yes, our gene pool is
more similar to the Cro-Magnon gene pool than the Neanderthal gene pool. It
would have been shocking if it had been otherwise. Why does this suggest to
you that "human DNA has basically remained the same as it was ten thousand
years ago?"

Note that there is a relevant part of the "out of Africa" replacement
hypothesis that was not mentioned in the text you pasted from the website.
The molecular data suggests that modern humans evolved from Neanderthal
ancestors quickly (perhaps over hundreds or thousands of years, not hundreds
of thousands) prior to expanding and replacing Neanderthals.
 
[snip]
 
>
> MR:
> This is true despite current existing genetic variation which has
> included some random mutations. Therefore, natural selection is
> certainly a transmission of genetic information across generations.
>
> GH:
> This is a very unorthodox view of what natural selection is. Again, the
> term used in biology that refers to "transmission of genetic information
> across generations" is "inheritance", which is hardly a synonym for the
> process of natural selection.
>
> MR:
> I understand that. Everything you read in a book doesn't mean it
> couldn't be supplemented or enhanced or at least at a more holistic
> level incorporated with other biological ideas. I understand when one
> reads the patterns of inheritance by Mendel natural selection isn't
> going to come up. However, humans are more complex than Mendel's peas
> and flowers and our patterns of inheritance involve the genetic
> transmission of naturally selected traits.

GH:
Do I read you correctly? Are you arguing that the traits of humans were
naturally selected but the traits of peas were not so much?
 
[snip]

> MR:
> Almost everybody on this newsgroup has conceded Darwinian evolution
> takes hundreds of thousands of years to effect changes.
>
> GH:
> I would be shocked if this were true.
>
> MR:
> You would? Why's that? I'm referring to Homo Sapiens here.

GH:
Not that it makes any difference to my argument, but the discussion on this
thread was not limited to humans. I have meant my arguments to apply
equally to all species. Maybe you would be interested in starting a thread
contrasting processes of evolution in the human lineage (or lineages of
"complex" organisms, whatever that might mean) with those in other species
(or simpler ones).

> MR:
> From what I've read Darwinian evolution does take hundreds of thousands of
> years to effect evolutionary changes and in the case of "major" changes
> longer. How have Homo Sapiens signifigantly biologically changed in the last
> ten thousand years? I await your answer.

GH:
It seems to me that it would be pointless to answer your question as
phrased, because you seem prone to saying that any change I might describe
would be "insignificant" to you. Can you rephrase the question that is less
contingent upon our opinions of what is or is not important in human
evolution?
 
> MR:
> Natural selection doesn't add information to gene pools but it is the
> main mode for transmitting information to gene pools.
>
> GH:
> I can agree with the statement that the process of natural selection
> transmits information from the environment to the gene pool, but not
> that it transmits information from one generation of organisms to the
> next.
>
> MR:
> You agree the process of natural selection transmits information from
> the environment to the gene pool but doesn't transmit that information
> from one generation of organisms to the next. I'm puzzled. Do you think
> that information transmitted from the environment to the gene pool by
> natural selection just sits stagnant in the gene pool? That's impossible
> for sexually reproducing organisms.

GH:
It is not stagnant. It decays (through mutation and genetic drift) unless
it is reinforced.
 
> MR:
> Mr. Hoelzer writes, "I would also agree with Tim that the typically
> strong effect of natural selection in decreasing genetic variation
> limits the extent of information that can be structurally configured in
> the gene pool." Yes but it also favors those qualities which have been
> selected by natural selection for organisms to optimally survive and
> reproduce.
> I've said as much myself on sbe, and I don't see how this contradicts
> anything I wrote.
> C'mon man, wake up! Did you wake up on the wrong side of bed this
> morning?
>
> GH:
> I might ask you the same thing. I can't see anything in what I wrote
> that would have lit your fire to this extent. In fact, I though that my
> post expressed a rational middle ground we could all agree on. I can't
> even tell from your post what I said that you disagree with. You have
> been saying "Yes, but" and the I neglected to say something. Did I
> actually say anything that was incorrect, or is it just my perspective
> that you object to?
>
> MR:
> No, I truly believe you are stating something that is incorrect and that
> is that you agree the process of natural selection transmits information
> from the environment to the gene pool but doesn't transmit that
> information from one generation of organisms to the next. Do you think
> that information transmitted from the environment to the gene pool by
> natural selection just sits stagnant in the gene pool? That's impossible
> for sexually reproducing organisms.

GH:
Answered above. I don't see how anything I have written suggested that the
only alternatives were selection or stagnation.
 
> MR:
> Mr. Hoelzer writes, "IMHO the interpreter-view of information assumed by
> Dawkins and most participants in this thread frequently leads to
> fruitless debates because there is no way to find agreement on the state
> of the interpreter. We do better, however, agreeing on the data. I think
> that we can agree on objective measures of variation and configurational
> topologies, which is why I personally prefer the objective information
> paradigm. Then you state, "there is value in a theory of signal
> detection and data interpretation, IMHO it should be clearly
> distinguished from theories of objective information content. In the
> latter view, information exists in the absence of observers, and is
> limited firstly by existing variation.
> How can you agree on "objective measures of variation and
> configurational topologies" in the absence of observers? Have you taken
> up the David Copperfield School of Evolution?
>
> GH:
> The purpose of having objective measures in science is to force
> agreement on the data. If my scale says that something weighs 2 grams,
> then so should your scale. You and I would observe and record the data,
> but the values recorded were independent of our disparate world views.
>
> MR:
> Yes, you stated, "You and I would OBSERVE and record the data. That
> means there is an observer.

GH:
The standardization of measurement means that we were OBJECTIVE observers.
It is the central role of SUBJECTIVITY in observation that I dislike in some
versions of information theory.

> Of course, I can agree with the idea of two different observers with disparate
> world views arriving at objective measurements. The way you initially came
> across is that objective information could result in the total absence of
> observers which of course is an absurdity.

My view is that objective information exists in the absence of an observer,
not it "could result in the total absence of observers." It seems to me
that you have been reading an awful lot into my posts lately that I did not
write or intend to imply.

Guy

Relevant Pages

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  • Re: Dawkins gives incorrect answer
    ... I think this is actually only one thing that natural selection is doing. ... human DNA has basically remained the same as it was ten thousand years ... our gene pool is more similar to the Cro-Magnon gene pool than the ... that it transmits information from one generation of organisms to the ...
    (sci.bio.evolution)