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Re: final thoughts

In a message dated 7/4/00 8:02:19 PM Pacific Daylight Time, 
kinman@hotmail.com writes:

> And of course, there are other purported 
>  holophyletic taxa proposed by cladists that are probably really 
>  (and they are more problematic when they go unrecognized).  So it goes.

First, if they are defined as "holophyletic", they cannot be paraphyletic.  
There is no way to make "the common ancestor of all living mammals and all of 
its descendants" paraphyletic.

Second, I would submit that an undiagnosed paraphyletic taxon is the only one 
with any real use.  If I have a bunch of taxa basal to a large clade, and I 
am not sure which (if any) of the basal taxa is closest to the large clade, I 
can slap a (potentially paraphyletic) name on the basal members as a 
convenient label for my generalizations about them.  But as soon as I 
determine that one of them is closer to the large clade, my ability to 
generalize about the members of the paraphyletic basal taxon, and thus the 
utility of that paraphyletic taxon, is compromised.

Nick P.