Moorad,
Stephen's posting has the basis for an answer to your question about the
increase in information in his "change in genetic characteristics of a
population over time." One change is duplication. A second change is
mutation. These two can produce more complexity. I keep running across
articles on genomics and proteomics that indicate a larger number of
genes in a family in "advanced" organisms than found in more "primitive"
ones. One gene is activated earlier or later than one with a similar
structure, and produces distinct results from the smaller number in less
complex creatures. Some of the genes apparently become quiescent, an
effect that one may expect from random changes. Indeed, I recall a
sidebar in a recent Science about a protein that has no use, but is
produced.
A third change is inversion; a fourth, relocation to a different
chromosome. These two processes strongly affect the ability to
interbreed, and may affect the timing of activation to have a major
effect on ontogeny. Polyploidy is a fifth change, which may be coupled
with interspecific crossing. I recall Raphanobrassica, radish and
cabbage, I believe. An additional factor is gene transfer. All these
produce changes in the genetic constitution of a population. We don't yet
have enough information to get points that we can connect, but the
indications are that they are coming, though billions of base pairs is a
lot more complicated than a few measurements to determine the orbit of a
comet or asteroid.
Despite the fact that we have genome sequencing for only a few creatures,
we can already see genetic connections. 98+% identity between Homo and
Pan, less with other anthropoids, etc. But a mammalian gene can
substitute for one in Drosophila in producing the structure of the very
different eyes, and it also works in cephalopods. People working in the
field can certainly add many more examples. They all tie together with an
indication that, in time, the dots will be so closely clustered that one
will not have to connect them. I won't bet on "don't know how" for long.
Dave
On Sat, 08 Dec 2001 15:54:33 -0500 "Moorad
Alexanian<alexanian@uncwil.edu>" <alexanian@uncwil.edu> writes:
> I can draw several points on the blackboard and connect them any way
> I want.
> The critical question is, do we have enough points to connect most
> of the
> points by a continuos curve? It seems that the evolution of man from
> lower
> forms would indicate an increase in information---more info is
> required to
> describe a man than a bacteria. When a physicist says he has a
> mechanism that
> describes a given physical process, what he means is that he has a
> mathematical theory whose logical consequence is that particular
> result. I
> must be honest and say that I do not really know what you mean by a
> mechanism
> that couses evolution--expect mere words. A more honest statement is
> that
> evolution happens but we do not know how. Moorad
>
>
> >===== Original Message From "Stephen J. Krogh"
> <panterragroup@mindspring.com>
> =====
> >Biological evolution is a change in the genetic characteristics of
> a
> >population over time. That this happens is a fact. Biological
> evolution also
> >refers to the common descent of living organisms from shared
> ancestors. The
> >evidence for historical evolution -- genetic, fossil, anatomical,
> etc. -- is
> >so overwhelming that it is also considered a fact. The theory of
> evolution
> >describes the mechanisms that cause evolution.
> >
> >Stephen J. Krogh, P.G.
> >The PanTerra Group
> >
> >================================
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