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Re: At long last! Turner, Makovicky & Norell on dromaeosaurids
David Marjanovic <email@example.com> wrote:
>> _Protarchaeopteryx_ might have been some form of parachuter or
> What, at that size? Isn't it way bigger than any known parachuter and at
> least the size of the very largest known gliders?
But would _Protarchaeopteryx_ have weighed any more than _Sapeornis_?
BTW, I'm not suggesting that _Protachaeopteryx_ was an accomplished
parachuter or glider. I also very much doubt that it was arboreal.
But if there were long, symmetrical feathers along the forelimbs, it
might suggest some "passive" aerial ability.
Speaking of _Sapeornis_, Turner &c recover this taxon as more basal
than _Jeholornis_, _Jixiangornis_ and confuciusornithids. This means
that the pygostyle of _Sapeornis_ evolved independently of that of
pygostylian birds (avialans), including confuciusornithids and
ornithothoraceans. Yet, the shoulder anatomy of _Sapeornis_ is more
primitive than that of the long-tailed _Jeholornis_ and
_Jixiangornis_, and the foot appears far better adapted for perching.
The early evolution of avialans was a weird place to be.