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APTERYX AND PROTOBIRD PHYLOGENY



APTERYX

In regards to Ralph Miller's question on paired oviducts in birds, the 
best known example is _Apteryx_ the kiwi.  As Alan Brush has pointed 
out, hawks, falcons, storks and some other birds also have 
(occasionally) paired oviducts.  Pierce Brodkorb, when he was still into 
neornithology, described paired oviducts in the Marsh hawk, but I forget 
the ref.  

Anyway, a few weeks ago Greg Paul made the claim that the lack of 
reversed halluces (not "halluxes") in the Chinese "protobirds", 
_Caudipteryx_ and _Protarchaeopteryx_, really doesn't mean that they 
cannot be more derived than _Archaeopteryx_ because _Apteryx_ also lacks 
a reversed hallux.  I didn't want to make a premature criticism so I 
looked at some refs and some actual kiwi specimens just to make sure; 
anyway, _Apteryx_ does have a reversed hallux as far as I can tell.  It 
is positioned rather proximally on the tarsometatarsus, but the position 
seems to be reversed.  

"PROTOBIRDS"

What does this tell us?  For one, it casts doubt on the assumption that 
the two "protobirds" are more derived than the famed _Archaeopteryx_ 
sp..  At the moment, I think that the best interpretation is to consider 
them outside of Aves (_Archaeopteryx_ + Neornithes).  The real question 
is, where do they fit?  I think that for the moment, _Protarchaeopteryx_ 
should be considered next to Dromaeosauridae, possibly allied with 
Velociraptorinae, and _Caudipteryx_ should be considered next to Aves as 
the sister group to the _Unenlagia_ + _Archaeopteryx_ + _Rahonavis_ 
group that Forster et al. considered.  

I must repeat again that the two animals show hardly any features that 
suggest that they are closer to Neornithes than _Archaeopteryx_ (ie. 
lack of dorsal ischial processes, presense of serrated teeth, two 
sternal plates, etc.).  The sternal characters and tail characters are 
rather meaningless, both can be considered homoplastic in light of the 
estensive avian characters that _Archaeopteryx_ has.  

Matt Troutman

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