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Re: MANIRAPTORA PREDATING _ARCHAEOPTERYX_



In a message dated 95-11-27 17:16:41 EST, Robert.J.Meyerson@uwrf.edu (Rob
Meyerson) writes:

>But if this is true, then can we truly say that Archy is a dinosaur?
>Further, if the BCF theory is right, then wouldn't all dromaeosaurs also
have
>to be removed from the dinosaur category?  Perhaps, I'm missing the point???
>
>

Not at all. It depends on your definition of a dinosaur and of a bird. If you
call Aves the clade of all archosaurs descending from the common ancestor of
_Archaeopteryx_ and extant birds, then Dromaeosauridae almost for sure and
probably a few other "theropod" families would become avian. That's not how I
would define Aves; I would call all dinosaurs closer to birds than to
phytodinosaurs Aves. So cladistically speaking Dinosauria divides into two
subclades: Phytodinosauria and Aves. Aves passes through basitheropods,
lagosuchians, herrerasaurian, and theropods, then heads for the birds, of
which at least one major branch is still extant and diverse; Phytodinosauria
passes through sauropods, prosauropods, and segnosaurs to ornithischians and
becomes extinct at the end of the Mesozoic. Details will be in the third
printing of _Mesozoic Meanderings_ #2. (Bye bye, Saurischia!)