Mario, you can find the discussion of this in Jesper Hoffmeyer's
book "Signs of Meaning in the Universe" 1996.
In short, there is no "blind seive". Any seive is an instrument
and somebody makes use of it, otherwise it is not a seive. What
we call "natural selection" (a very confusing term!) is a mechanism
by which the population probes the environment and selects which
organisms should reproduce and which should not. Unfortunately,
many biologists like Gould can think only of individual adaptations
and dismiss ideas of adaptations at higher hierarchical levels
(e.g., populations). In order to make use of "natural selection", a
population must "remember" which organisms performed best; thus, it
needs inheritance which is population's memory. Also, it needs some
sort of a search engine which generates variability. This engine
includes mutations, recombinations. Epigenetic constraints are used
to prevent blind repeating of previous mistakes. All these mechanisms
are adaptations at the population level which were selected at a
higher level of "natural selection". There is a hierarchy of
"natural selections" that correspond to different time scales.
Michael Conrad wrote a book "Adaptability" in which he explains this
hierarchy of natural selections.
However, it is impossible to consider natural selection at all
infinite levels. Thus, for practical purposes, we cut it at some
level and call everything that is above "physics". For example, we
can consider selection of individuals without thinking of adaptations
at the population level. This is like an 8-digit calculator that cuts
off extra information. But people like Gould think that the 8-th digit
is the last one and there is nothing beyond.
The term "freedom" has a lot of connotation. But for scientific
purposes we can view freedom as making use of variability. Obviously,
it is outside of physics because physics does not study usefulness.
But biology studies adaptation which is the same as usefulness. Thus,
freedom can be studied within biological sciences. The most simple
example of freedom is mutation.
>Why should we need QM all of a sudden to explain consciousness, while we could
> do
>without to explain the rest of evolution? This is a bit like pretending
that, to
>explain human existence, you need some kind of deus ex machina solution.
Here I agree with you completely! There is no need for QM to explain
variability. In most cases we simply don't need to explain variability,
we simply postulate it (the same 8-digit calculator!). I don't mean to
forbid using QM for explaining evolution or free will. I just say that
we can understand a lot about evolution and free will even without QM.
May be eventually QM or some other physical theory will be able to add
some details, but now we are not talking about details.
-Alexei
-------------------------------------------------
Alexei Sharov Research Scientist
Dept. of Entomology, Virginia Tech, Blacksburg, VA 24061
Tel. (540) 231-7316; FAX (540) 231-9131; e-mail sharov@vt.edu
Home page: http://www.gypsymoth.ento.vt.edu/~sharov/alexei.html