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RE: PNAS



> The main problem that folks such as Ruben seem to be having
> is the notion that a dinosaurian origin of birds absolutely
> necessitates a ground-up origin of flight.

Also (in this particular case) they are ignorant of the difference between Aves 
and Paraves.

Or what bearing would a microraptorine dromaeosaur have on the evolution of 
birds? It's like arguing cows (as they are generally imagined) can't exist, 
since they are "supposedly" terrestrial, while whales are aquatic.

In reality, the new study just proves Barsbold's prediction of more than 25 
years ago: that "ornithization" (the evolution of "bird-like" exaptations) 
among maniraptorans was so widespread that an "bird-like" bauplan is quite 
likely to have evolved several times independently - even though *most* 
maniraptoran lineages never evolved a sufficient combination of "avian" 
features to a sufficiently refined form to achieve flight. 

Or, in brief: Aves monophyletic, "birds" polyphyletic.


Eike

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