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.
>People try to handle it by inventing various patches because they
>cannot leave the familiar dogma that heredity and selection are
>separated processes.
>
>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.
>
>>Possible, all kind of books have been written. But this is not the standard
>view
>> of
>>biology and there are good reasons. (See Evolution by M. Ridley as cited
in the
>>language article (see below): Group selection can occur, but is limited and
>> mostly
>>to weak to overwhelm natural selection.
>
>Standard view is not always the best one... Most of the critique
>of group selection is based on misunderstanding. Models of
>Maynard Smith consider temporary groups that are only partially
>isolated. It is obvious that group selection is not very effective
>if groups are not well isolated. However, species are very well
>isolated and group selection at the level of species is a normal
>thing.
>
>Also, there is a false idea that any adaptation should be
>either an individual adaptation or a group adaptation. Most biological
>processes have their effect on multiple hierarchical levels. Thus,
>they have meaning at several levels. Dawkins says that if we can
>"explain" some adaptation by individual selection there is no sense
>to look at group selection. This is stupid, because any individual
>adaptation may have additional effects on higher hierarchical levels
>and at longer time scales.
>
>>I would be the first to say that natural selection has limited
applicability.
>> E.g.
>>I' d say that the origin of life cannot be explained by NS, while the
standard
>> view
>>is that of the RNA-world whereby 'self replicating' molecules undergo
natural
>>selection, because of differential reproduction rate (which by the way is
not
>> the
>>same as differential survival rate: survival is unimportant in biology,
>> reproduction
>>is). Also selection comes only after variation has been 'created', through
>> mutation
>>and recombination (through symbiosis, sexual (bilinear) recombination or
>> cultural
>>(multilinear) recombination). A lot of evolution can be explained through
the
>>absence of selective constraints, e.g. when a new building plan comes into
>being
>>like was the case for animal multicellularity: at that moment any variation
>goes
>>because there is nothing like it and the niche is empty. This empty niche,
>> always
>>open for more complex organisms may explain why evolution almost inevitably
>> leads to
>>more complexity: there is always room for more complex organisation.
Evolution
>> is
>>open ended towards more complexity, (more complex organisms initially
have no
>>competitors).
>
>This sounds close to what I think.
>When we found that some theory does not work reliably in all
>areas we have 2 options: (1) delimit the area where the theory
>seems to work more-or-less satisfactory, and invent patches for
>those areas where it does not work, or (2) modify the theory so
>that it will work well in a much wider range of situations.
>Traditional Darwinism (including Dawkins and Gould) use the first
>option. Some people including me use the second one.
>
>>I'd hesitate to call mutation freedom, since it is deterministic, but still
>then
>>this has a different connotation than free will.
>
>Why mutation is deterministic?
>
>-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
>
>
----------------------------------------------
Appreciatively,
John J. Kineman
Bear Mountain Institute
1101 Bison Dr.
Boulder, CO 80302
BMI@bayside.net
http://www.bayside.net/NPO/BMI