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Re: Stephen Czerkas' dromaeosaurs = birds but not dinosaurs



Stephan Pickering (stefanpickering2002@yahoo.com) wrote:

<I do not, on the basis of his forthright abstract, grasp how he can posit
a non-dinosaur origin for dinosaur dromaeosaurs, unless his converted
clade names are not constructed according to rigorous phylogenetic
systematics.>

  First, there cannot be any such thing as a "converted clade name"
until/if PhyloCode is published. Otherwise, any new definition (and
Czerkas does not use them) is just a new definition, and any taxa are just
taxa.

  And second ... yeah, Czerkas doesn't use definitions in the PT
(phylogenetic taxonomy) sense (de Quieroz and Gauthier, 1991 & 1992). A
good deal of practicing systematists that describe dinosaurs do not even
use cladistics. Hardly a criticism....

  Cheers,


=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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