"Jim McGinn"  wrote in message
>
> NS is not a force, it's a process.
>
OK. Strictly we shouldn't say "the forces of evolution" or
"genetic drift
can be an evolutionary force". These are processes, whilst force requires
energy acting to move matter in a given direction.
However natural language does extend the meaning of words.
>
> But, to answer your question, I have no trouble at all with the notion
that
> the process of NS eliminated the furry tail allele.
>
For NS to eliminate the furry tail allele, the allele has to be selected
against. If the allele also made the mouse's coat slightly lighter, and this
made the mouse more conspicuous, causing the hawk to attack it rather than
its fellow, then this would be a clear case of NS at work.

However the allele was recessive, and wasn't a contributing factor to the
hawk's decison to attack the mouse.

It may well be that no available genotype (combination of the genes present
on the island) would have made any difference - the hawk could have caught
either mouse but not both of them. Thus NS isn't working at all.

However what if we accept that the furry tail allele itself isn't
contributing to the mouse's demise, but the mouse has another allele, maybe
for short legs, which is making it run slower and thus causing the hawk to
attack it rather than the other mouse? Now NS is working, on the "short
legs" allele.

So has NS eliminated the furry tail allele? No, because genes get shuffled.
It is pure chance, or caused by biochemical events in meiosis, that the
furry tail allele ended up in the same body as the short legs allele. NS
only works if the allele contributes to its own chance of survival.
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