Re: Dino Birds (was Re: Dinosaur = extinct animal)

[Dinogeorge@aol.com]

In a message dated 7/12/99 9:00:56 AM EST, cbrochu@fmppr.fmnh.org writes:

<< The overall point is that paraphyletic assemblages, above the species
 level, are subjective, have no biological reality, and are not
 recognized in modern systematics. >>

Paraphyletic taxa certainly have "biological reality," whatever that is. If 
monophyletic taxon A and included monophyletic taxon B are "biologically 
real," then so is the paraphyletic taxon A-B, the set of organisms that are 
in A but not in B. Whether or not paraphyletic taxa are to be admitted into 
taxonomy is a subjective philosophical decision, just like the choice of 
which taxa should be defined as monophyletic and which might be most useful 
as paraphyletic. Despite the cladistic prejudice against them, there are 
still plenty of paraphyletic taxa recognized in modern systematics, 
including, e.g., the genus Australopithecus: all australopithecines that are 
not in the genus Homo. Among dinosaurs, the genus Hypacrosaurus is probably 
paraphyletic, since it doesn't include the species in the probable descendant 
genera Corythosaurus and Lambeosaurus (see Currie & Horner on Hypacrosaurus 
stebingeri), and the genus Chasmosaurus, since it doesn't include the species 
in the probable descendant genus Pentaceratops (see Lehman on Chasmosaurus 
mariscalensis).