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Re: Archaeoraptor et al.



In a message dated 9/7/02 8:40:02 AM EST, stefanpickering2002@yahoo.com 
writes:

<< I do not believe I have miscategorized dinogeorge's classificatory 
schemes, since, by his usage, he does not accept the factuality of "birds" 
being theropods. >>

Like I said, it's not that birds are theropods, it's that theropods and 
ornithischians and sauropods are all birds. Quadrupedal (in the case of 
sauropods and some ornithischians), wingless, long-tailed birds.

The way I see it, "birds" are any tetrapods closer to modern birds (such as 
the robin Turdus migratorius) than to modern crocodylians (such as, say, 
Crocodylus porosus), which are their nearest living relatives. This stem 
group I call Ornithes (Greek for "birds"). It happens to include all the 
dinosaurs, which are among the "nonavian ornithans" (modern birds are 
included in the clade Aves, which is best defined as the common ancestor of 
all extant birds plus all its descendants, a crown group: we might call these 
"avians" or "avian birds," for example).

So the term "Nondinosaurian: Bird" can have a perfectly valid meaning. 
Indeed, I have had to exclude just such animals (among others), as a general 
rule, from the Dinosaur Genera List, because otherwise the list would be so 
replete with the thousands of generic names of Cenozoic and modern birds as 
to lose its usefulness as a "dinosaur list."

In any case, it is less important to conform one's work to what others may 
think of what birds and dinosaurs are than to clearly state at the outset of 
one's own work what one's >own< definitions of birds and dinosaurs are. 
That's the problem you had when you read "Nondinosaurian: Bird" in my 
listing; I didn't accompany the listing with my working definitions of birds 
and dinosaurs.