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Re: Re: Batch o refs



>In a message dated 95-09-29 14:20:45 EDT, Thomas_R_HOLTZ@umail.umd.edu (th81)
>writes:
>
>>Of course, if you add in parataxonomy, you can add dozens upon hundreds upon
>>thousands upon... of additional parataxa for any one genus (e.g., all
>>tyrannosaurids except T. rex, all theropods except T. rex, all dinosaurs
>>except T. rex, all archosaurs except T. rex, all reptiles except T. rex,
>>through tetrapods, verts, deuterosomes, etc.).   ;-)
>>
>>
>
>But we don't DO this! We exercise some restraint (a term certain cladists
>might want to become familiar with).

While some cladists, in their youth perhaps, did name every node on their
cladogram, that is hardly standard practice.

As Kevin Padian & I will advocate at SVP, only robustly supported clades
should be named.  As deQuieroz (hope I spelled it correctly this time) and
Gauthier have shown, it is a simple enough (and useful) practice to name a
node-based clade and a stem-based clade for each robuts group.  For example,
for the node-based Reptilia (the most recent common ancestor of turtles,
lepidosaurs, and archosaurs), there is the stem-based Sauropsida.  Thus,
while most sauropsids are reptiles, some (e.g., mesosaurs) are not.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist
Dept. of Geology
University of Maryland
College Park, MD  20742
Email:Thomas_R_HOLTZ@umail.umd.edu (th81)
Fax: 301-314-9661
Phone:301-405-4084