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Re: Fixing dinosaurian carnivour question
In a message dated 5/27/99 7:48:38 AM EST, th81@umail.umd.edu writes:
<< There is a big difference in calling _Megalosaurus_ or _Iguanodon_ "extinct
avians" (something very few would do) and in calling them "non-avian
dinosaurs" (something a lot more common). >>
Well, the fact that they're extinct is irrelevant to their classification,
but the notion that they're "non-avian" has everything to do with their
classification. So this is like comparing apples with Audi automobiles.
Classified this way, with Aves containing Dinosauria, one might call
_Megalosaurus_ a "carnosaurian avian," and _Iguanodon_ an "ornithischian
avian"; and both would be "dinosaurian avians" (along with modern birds,
_Triceratops_, and so forth).
Incidentally, "non-dinosaurian avians" in this scheme are the archosaurs
along the stem joining Dinosauria to the common ancestor of crocs and birds
(most of which, by the way, were pre-feathered arboreal climbers...).