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Re: *Utahraptor* and Polyphyly of Recent Dromaeosaurids
Josh Smith wrote:
<The dentition of _Dromaeosaurus_ are actually quite distinct
from anything currently being referred to "tyrannosaurids">
Oh, I completely agree. My point was to consider the deflected
mesial carina in premaxillary teeth, or the distal twist. This
curious feature led Matthew and Brown to refer the form to
"deinodonts." My statement was more in regards to a basic,
robust maniraptoriform that bore a great deal of similarity to
tyrannosaurids, as does *Itemirus*, for instance. I'm ambivalent
on *Itemirus* until I see the paper and a good photo*.
<<7. form of the denticles of the teeth;>>
<This character may or may not turn out to be robust and valid.
At this point I am voting for yes, IF the proper homework is
done. However, the amount of homework is rather substantial ...
and to my knowledge, there is currently not a single paper
anywhere in the world where the morphology (not size per unit
distance) of theropod denticles has been systematically examined
in the detail necessary to substantiate the above statement.>
My mistake, I didn't mean to refer to the morphology, but the
relative morphology of the carinae, which Currie, Rigby, &
Sloan, 1990 have undertaken a study, and which I believe is also
being worked on (morphology of denticles). A 1996 short paper in
Geodiversitas (? -- probably not the right journal, I'm away
from my references right now) suggests some comparative work is
being undertaken on a strict group (withing a single horizon) --
which is largely what Currie et al., 1990, did.
Anyways, this is a character I almost didn't include because
of its prescence in troodontids: the posterior denticles are on
the order of 1.5 or more the size of the anterior denticles. <shrug>.
Jaime A. Headden
Where the Wind Comes Sweeping Down the Pampas!!!!
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