Re: Sinocalliopteryx (Theropoda: Compsognathidae) ate confuciusornithids and dromaeosaurids

[David Marjanovic <david.marjanovic@gmx.at>]

> I doubt if either of these  studies are the last word on the topic.
> However, the assumption that basal (non-ornithothoracean) avialans
> were capable of powered flight is on very thin ice. Not just because
> of the conclusions of the above two studies, but also the inferred
> absence of an elevating supracoracoideus.

What about the deltoideus? That's what bats use, and apparently what 
pterosaurs used, too. Indeed, in eumaniraptorans, the deltopectoral 
crest is huge even in *Ichthyornis* (an animal that doesn't make sense 
as anything but a powered flier).

> In any case, it is highly  unlikely that confuciusornithids (and other
> basal avialans) were capable of a ground-level take-off.

Assuming they were capable of powered flight in the first place -- why? 
Pigeons need the supracoracoideus to take off from the ground, but other 
birds don't. After all, almost all the force for taking off comes from 
the hindlimbs. Even hummingbirds don't just stand there and flap, they 
jump off.