> Thanks Alexei, this is very helpful!! And I think, although my descriptions
> are less precise, there are considerable overlaps with what I'm also trying
> to say. These statements of yours seem very clear. Do you also consider the
> possibility of introduction of variability as "innovation" at the
> phenotypic level,
Am I right to say that this question comes down to asking: "Do you think that
some
kind of Lamarckism is possible?"
> and to what extent are the hierarchical levels also
> mechanical? I think they are both and would specifically name free-will as
> an independent factor.
To make things clear: I do not bring up free will each time.Since John does,
could
he specify exactly what he means with it. I don't want to, but we are forced to
discuss the concept if John (and Alexei?) think that it is essential to
understand
evolution.
>
>
> At 11:04 AM 9/2/98 -0400, you wrote:
> >>Mario Vaneechoutte wrote:
> >>Well, this puts thing on their heads! The population does not probe
> anything,
> >> I'd
> >>say.When you have variation on a theme, then none, one, some or all of the
> >>variations will be able to exist in a certain environment (which contains
> the
> >> other
> >>variations as well of course). Whether we call this a seive or not, it is
> what
> >>selection is about in general (natural or not). I find it truly confusing
> and
> >> even
> >>erroneous to say that there is a population which probes the environment and
> >> which
> >>selects. Selection is something which is the result of having certain
> >> environmental
> >>conditions and variations on a theme with possibly different 'viability' in
> >that
> >>environment.
> >>There is no 'which SHOULD reproduce or not'. Those that could reproduce are
> >> still
> >>here, that's all.
> >
> >Darwin suggested considering heredity, variation, and selection as
> >3 seperate processes that together end up in biological evolution.
> >For didactical purposes it may be convenient to separate these
> >3 processes but in fact they are 3 different views on the same process.
> >You cannot define fitness without considering heredity. If an elephant
> >gives birth to a fish, there is no fitness and no natural selection.
> >All what you said is a good simplification which is nice for teaching
> >evolution at college. But it does not capture deeper layers. If you
> >define fitness as the mean number of offsprings per parent you will
> >soon discover that this fitness is not always maximized in evolution.
I tend to disagree, Alexei. Could you give an example of the latter.
> >People try to handle it by inventing various patches because they
> >cannot leave the familiar dogma that heredity and selection are
> >separated processes.
Selection is a separate process. Helium has two protons (the theme). It can have
1
to 5 neutrons (the variations on a theme). Only configurations with 1 and 2
neutrons are stable under the current physical laws in the universe (the
environment). The other 3 configurations will disappear through radio active
decay
(we observe selection, which is the outcome of having an environment and having
variations on a theme whereby some variations fit better in the environment than
other variations). This is an example of selection which has nothing to do with
heredity. Selection is almost tautological: any time there is variation none,
one,
more or all of the variations will better fit into certain environmental
conditions. Of course.In natural selection we have the "special" case (but of
course widely spread, since life was so successful) whereby selection occurs
among
the theme of autonomous duplication as became possible with the first cell.
I don't see how this is a simplification.
> >
> >Death is not defined by physical conditions because there are
> >various ways to live. In a way, death is optional. An organism
> >dies only if it could not find a good option of how to live.
??? I do not understand this.
-- Mario Vaneechoutte Department Clinical Chemistry, Microbiology & Immunology University Hospital De Pintelaan 185 9000 GENT Belgium Phone: +32 9 240 36 92 Fax: +32 9 240 36 59 E-mail: Mario.Vaneechoutte@rug.ac.be