>  My understanding of it is that intelligent design theorists agree that 
> microevolution occurs, but do not believe there is sufficient 
> justification for macroevolution.  Is this also your understanding of the 
> intelligent design position?  How would you respond to that position?
>
>Rod
>


I would argue that this is a false dichotomy.

Remember that the process of by which new species are formed (speciation?) 
is thought to be caused by a sum of micro-evolutionary processes in 
reproductively isolated populations.

Suppose you have an interbreeding fish population in a lake.  Some natural 
event - say an earthquake - creates a barrier and results in the formation 
of two lakes.  The populations are now reproductively isolated.  Selective 
pressures in one of the lakes might be slightly different than in the other 
because one lake gets a bit more sunlight than thre other, supporting 
different algae populations.  Selection occurs in both populations - gene 
frequencies change - but differently in the two populations.  Over the long 
haul, the two populations become different enough that interbreeding would 
in fact be impossible were they to be put back together.  Now there are two 
species where there was once one - but curiously neither species has 
undergone "macro-evolution" - the two populations have simply undergone 
different microevolution.

Evidence?  Of course, all evidence of past evolution is indirect.  But the 
evolution of marsupials in a reproductively-isolated Australia is one 
example.  Darwin's Finches are of course another classic example.

-- Jim Dougan



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