Re: paraphyletic Dromaeosauridae (Pyroraptor)

["Ken Kinman" <kinman@hotmail.com>]

     Oh, I wouldn't ever consider birds as an outgroup either (YIKES).  
What I meant was that perhaps ornithomimes might be too far removed to give 
eumaniraptorans a rigorous rooting.  If we knew for sure that Troodonts are 
the closest relatives without actually being a eumaniraptoran, then it would 
be a good outgroup (but some topologies make troodonts eumaniraptoran).
     It seems to me that specifying a group of caenagnathoids 
(oviraptorosaurs) as "the outgroup" might bear some fruitful results.  And I 
might note in passing that I might not be as concerned about the size 
problem, if Pyroraptor is a "utahraptorine".  But we would probably expect 
to find smaller such forms earlier in the Cretaceous.
     EGAD, it just occurred to me that if "utahraptorines" are basal to the 
dromaeosaur-bird split, then cladistically they would not be 
eumaniraptorans.  If that turns out to be the case, then an analysis of 
eumaniraptorans using troodonts as the outgroup might not be such a bad idea 
either (but caenagnathoids would be safer for now).
     I'm also beginning to wonder if perhaps _Unenlagia_ shouldn't be moved 
down a node or two (up in my classification), perhaps next to Bambiraptor 
(between velociraptorines and Sinornithosaurus).  I'm starting to doubt the 
closeness of Unenlagia to Rahonavis.
              -----   Ken
****************************************
Jaime wrote:
>   However, back to rooting, this isn't a problem. In these analyses, birds
> were not the only taxa in the matrix, so were oviraptorosaurs and
> troodonts and ornithomimes. To root a taxon in a cladistic matrix, you
> have to explicitly tell it that taxon is the outgroup, and this is only
> done if the group appears at the base or is not a member of the groups
> studied to begin with. so a non-maniraptoran would be chose, e.g.,
> ornithomimes, and the rest "fall as they may." It would be very unwise,
> and unpracticed to my knowledge, for the taxa to be rooted on birds.
>
> =====
> Jaime A. Headden

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