Re: Dawkins gives incorrect answer

• Previous message: Michael Ragland: "Interaction between epigenetics and genetics"
• In reply to: Guy Hoelzer: "Re: Dawkins gives incorrect answer"
• Next in thread: Michael Ragland: "Do you disagree with the Modern Synthesis Mr. Hoelzer?"
• Messages sorted by: [ date ] [ thread ]

Date: Sun, 22 Aug 2004 00:32:33 +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.

MR:
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:
I agree. Just being universal.

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
thought 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?"

MR:
Essentially, my statement human DNA hasn't changed that much in 10,000
years is partly a guess. Part of the article stated, "Fossils of two
anatomically modern H. sapiens found in a southern Italian cave yielded
mitochondrial DNA, which is inherited from the mother, say Giorgio
Bertorelle of the University of Ferrara in Italy and his colleagues. The
DNA contains chemical sequences that resemble those of people today but
differ substantially from those previously isolated from four Neandertal
specimens". So there are DNA chemical sequences of Cro-Magnon's which
resemble humans of today. I'm not even sure how long ago Cro-Magnon
lived. My "guess" is at least 10,000 years ago if not longer. How many
DNA sequences would have to be analyzed to "prove" human DNA hasn't
changed that much in 10,000 years? I don't know. Apparently, however,
the similarity of Cro-Magnon DNA chemical sequences to modern humans and
the dissimilarity of Cro-Magnon to Neanderthal DNA supports the idea we
came from Cro-Magnons and buttresses the Out-of-Africa hypothesis.

GH:
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.

MR:
Interesting.

[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?

MR:
No. You missed or ignored my main point. The dear little pea was just as
much naturally selected.

[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:
I'm not qualified to do that. I could do alot of research on the
internet and attempt to do what you suggest but I don't have a
particular interest.

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:
Yes, when it comes to evolution I'm very species egocentric. I
appreciate many facets of nature and other animals but I'm very focused
on human evolution or slowness thereof. Sure, I'd be more than welcome
to hear what evolutionary changes have occurred in the last ten thousand
years. I'm sure its a boatload.

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:
No, you stated, "It is not stagnant. It decays (through mutation and
genetic drift) unless it is reinforced." I accept that. What you seem
not willing to acknowledge is that natural selection transmits
information from one generation to the next. This is not inconsistent
with mutation or genetic drift.

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.

MR:
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.

GH:
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.

MR:
Sounds contradictory to me.

"It's uncertain whether intelligence has any long term survival value.
Bacteria do quite well without it."
 Stephen Hawking

• Previous message: Michael Ragland: "Interaction between epigenetics and genetics"
• In reply to: Guy Hoelzer: "Re: Dawkins gives incorrect answer"
• Next in thread: Michael Ragland: "Do you disagree with the Modern Synthesis Mr. Hoelzer?"
• Messages sorted by: [ date ] [ thread ]