"Malcolm"  wrote 

> > If they don't claim one to one correspondenc then Genetic
> > Drift is refuted as a cause separate from NS.  How is this
> > not obvious to you.  (I suggest reading back through this
> > thread.  Once we established a distinction between chaotic
> > causation and chance (which is not causal) this discussion
> > was over: genetic drift is a result of the gambler's
> > fallacy, nothing more.
> >
> Entering the lions' den here, however.
> 
> A random process can be causal. 

Obviously.  Read back through the thread, you'll see that 
this was never at issue.

> Similarly genetic drift tends to cause alleles to be 
> eliminated.

If you read back through the thread you'll realize that 
"genetic drift," is nothng but an observation that has 
been mistakenly designated as causal.  So, GD doesn't 
cause anything.

 Given a
> sufficient number of generations, it is statisitically inevitable that one
> allele will become fixed.

What causal forces--if any at all--are associated with 
an allele becoming fixed?  (Think carefully before you 
answer.)

(Don't tell me, IYO, 'chance' is the causal force.  Right?)



> Natural selection can only operate where there is a difference in fitness
> between two alleles.

Nonsense.  There's never not a difference.  (Fitness is 
partly a function of the location of the entity involved.  
Two different alleles (or the genes thereof) cannot be 
located at the same place at the same time.)

 Then the more fit allele will tend to be fixed. However
> if the fitness benefit is small and the allele is initially rare, then it
> might be lost through genetic drift. That is how the two processes interact.

You are not addressing any of the issues raised in this 
thread.  All I see here is the typical, pseudo-scientific 
hyperbole of GD.  There's nothing new here at all.  I 
suggest dealing with my arguments directly.

> 
> Any non-human agency that affects fitness qualifies as a natural selective
> force. Eg an asteroid hitting the earth might eliminate big animals that
> don't hibernate. Genetic drift doesn't affect the fitness of the population
> it operates on so it doesn't qualify as NS.
> 
> However genetic drift could be a selective force in the same sense as the
> asteroid. Consider you have a parasite, and several populations of hosts who
> have diverged due to genetic drift. A parasite that is capable of adapting
> to several slightly different immunoglobin genes might be selected for, and
> in this sense genetic drift of the host has been a causal evolutionary
> factor.

You indicated no cause here.  You asserted a cause at the 
beginning of this paragraph then circled back around to 
claim a cause.  Again, I suggest dealing with my arguments 
directly.  And you can only do this by reading back through 
this and related threads.


Jim
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