RE: Random thoughts

From: Moorad Alexanian (
Date: Mon Oct 29 2001 - 21:13:22 EST

  • Next message: Marcio Pie: "RE: Random thoughts"

    >===== Original Message From Marcio Pie <> =====
    >Hi Moorad,
    >> The following has been whirling in my brain for some time. I believe that
    >> the study and attempts of predicting our weather is a much simpler problem
    >> than the study and attempts of predictions one can make in evolutionary
    >> theory. It is well-known that the study of our weather leads to
    >> deterministic chaos, via the Lorenz equation and the so-called butterfly
    >> effect. Now, why doesn't the same occur in any theory that attempts to
    >> predict the outcome from natural selection and random mutations?
    >Because they represent different classes of phenomena. Chaos is
    >deterministic; you can predict the future exactly if you know the
    >equations and the initial conditions. OTOH, evolution has a very strong
    >component of randomness, both through mutations and drift.

    One cannot make long range prediction in system that are very sensitive to
    initial conditions. In addition, randomness would make forward or backward
    prediction even less possible.

    >> In
    >> particular, why can't two totally different species, say a gnat and man, be
    >> the evolved outcome of a common entity in the past? In addition, why should
    >> two species that are close in DNA space now be considered to have evolved
    >> from the same entity in the past?
    >They could, but that wouldn't be the most parsimonious explanation given
    >the available evidence. I think most biologists are aware of that.

    That is the point that from the available evidence one cannot derive a
    definite conclusion.

    >> I believe that such complex systems are
    >> chaotic and attempts of predictions are totally baseless. Also, working
    >> backwards in time is useless and arbitrary. Moorad
    >Complex systems are not chaotic. Some people from the so-called
    >"complexity sciences" suggest that the place where organisms should be is
    >in the border between order and chaos. Too much homeostasis prevents
    >evolution; not enough homeostasis would lead crutial processes such as
    >development to be too fragile.

    I think that is just more jargon and less science. That is the difficulty with
    a theory that is just words and can never attain the rigor of a true science.


    >Marcio R. Pie
    >Department of Biology
    >Boston University
    >5 Cummington St.
    >Boston, MA 02215
    >Phone: (617) 353-6977
    >FAX: (617) 353-6340

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