Re: Evidence For a Feathered Velociraptor...

[ptnorton <ptnorton@suscom-maine.net>]

Graydon wrote:

> But I don't think it _is_ a correlation between quill knobs and powered
> flight.  I think it's a correlation between quill knobs and aerodynamic
> load on retrices.

Exactly right, in my opinion.

> We know there are other ways to deal with feather control and anchoring,
> because there are modern volant species as don't have quill knobs

Really? Which ones? (I'm just curious, not questioning.)

It's worth noting that some extinct and presumably volant species, such as 
Archeopteryx, have (at least so far) not been found to have quill knobs. 
This has always been troubling to me, since the biomechanical advantage of 
quill knobs seems to be to transfer aerodynamic forces from the feathers 
through the skeleton to the animal's center of mass.

I would also note that concerns about damage to elongated ulna remiges may 
be a red herring, since aerodynamically functional feathers on the arms of 
an animal such as Velociraptor could have helped it do battle with its feet 
while keeping its arms *away* from struggling prey.  In battle and in prey 
aquistion, birds will use their wings to bring the hind limbs higher so that 
the feet will make contact first.

PTJN