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From: sa209@utb.shv.hb.se (Claes Andersson)
Subject: Re: Lamarckian Evolution
Message-ID: <1995Jan19.165905.13105@gdunix.gd.chalmers.se>
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Date: Thu, 19 Jan 1995 23:15:49 GMT
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mthayer@ix.netcom.com (Michael Thayer) wrote:
>In <1995Jan18.165850.75699@ucl.ac.uk> Chris Harris
><charris@cs.ucl.ac.uk> writes:
>
>>
>>If Lamarckian evolution is a possibility (and I might as well add here
>>that I don't consider it so) then how do its exponents explain the
>>amazing changes it must make to our genomes. If an organism picks up,
>>during its lifetime, a number of useful traits, which it somehow
>>genetically encodes, where does it put them? Does it just add these
>>sequences on to the end (i.e. new genetic material) or does it
>>replace ones that are already there so that the genome length is
>>preserved? If the latter, then how does it do that, and how does it
>>decide which ones to 'get rid of'. If the former were the case then
>>our genome would be getting longer and longer...
>>
>All you have shown is that the genome is NOT the whole repository of
>inherited characteristics.  This would certainly be posssible in alife,
>as the "genome" used is a logical, not physical one, and why couldn't
>this be true for life?
>Michael
>
 No it can't. Look at it in this way: A gene is of course something that has
influence over its own existance. To have an influence it must be selected
in someway and what is selected is its phenotypic effects. But a selection is
meaningless if nothing is selected (of course) and therefor it must have a
continuity in time. The DNA self replicates in the meiosis, so far so good.
But crossover occur and this threatens to cut a gene in two. Therefor, its
continuity is defined by the length of the gene, and the selectability of its
effect.

 As you see, there is NO candidate gene in a living species but genes can
can be anything. A gene in a GA is a gene for the GA not for us, of course.
Nothing in the cytoplasma (the only possible candidate) qualifies to be called
a gene.

Claes Andersson. University of Bors. Sweden



