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Re: New Jeholornis specimen



Well this is nice. With its long tail Jeholornis kills yet another 
Archaeopteryx character used to defend the latter's position closer to modern 
birds than longer tailed dromaeosaurs and so forth. Likewise Confuciusornis 
has a much less derived postorbital bar than less derived Archaeopteryx. It 
is possible that Arch evolved its shorter tail independently, or that there 
was one or more reversions to longer tails post Arch. 

Yet another example that cladistics is at best hard pressed to handle the 
degree of reversal, parallalism, and convergence going on in the mosaic 
development of basal birds that had not yet evolved far from the dinosaurian 
grade, and were often losing and perhaps even reevolving flight. Cladistics 
is one important tool for restoring paleophylogentics, but not the only one, 
and in this case is inferior to assessing the relative derived degree of 
flight adaptations that are present. 

G Paul