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Jon Wagner, our favourite cladist (sorry Jon) writes..
> d) even then, there are possible troodontid teeth in the
> Morrison [sic?]
You are probably referring to the tooth-based taxon _Koparion
douglassi_. Its describer and namer, Dan Chure, no longer thinks that
_Koparion_ is a troodontid (J. Harris pers.comm. 1997).
With regard to John's assertion that uncinate processes are
perhaps phylogenetically informative, Jon also said...
> Why? Why? Whywhywhy?
> ON a different suject, is there current aggreement on the
> presence or absence of uncinate processes on non-avialan dinosaurs?
I am pretty confident that the fighting _Velociraptor_ specimen has
uncinate processes preserved _in situ_. Anyone with reference to a
good photo of the specimen can verify this (I do not have such a
photo to hand right now).
John and I discussed uncinates the other day and (perhaps) unlike
him, I do not regard them as phylogenetically informative, mainly
because their distribution among taxa is so strange. While
_Velociraptor_ has them, _Archaeopteryx_ does not (and I do think
that _Archaeopteryx_ is closer to other birds than are
dromaeosaurids). Greg Paul thinks that a process figured in Ostrom
(1979) is an uncinate from _Deinonychus_, but this is difficult to
prove. At last some enantiornithines have them. They appear primitive
for ornithurines (they are very evident in _Hesperornis_), but appear
to have been lost several times among neognathans (emus and screamers
lack them). And before some of you start to speculate, there is no
correlation between flightlessness and/or aquatic/amphibious habits
with loss of uncinates, as numerous groups of flightless and/or
aquatic/amphibious birds have them.
Before I consult Baumel et al.... time to ask the ornithologists - do
the rib's uncinate processes have a known function?
"Now nothing can stop us in the raptorisation of Earth!"