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Re: Anchiornis huxleyi
> I think the absence of asymmetric remiges is a powerful
> argument that
> the Anchiornis huxleyi was neither a powered flier _nor_ a
> distance glider.
I don't know about that, too me it just looks like it was using them for
aerodynamic purposes, I'm not calling it a distance glider, but perhaps the
equal of a flying squirrel, or one of those gliding snakes.
In my mind the asymmetry is a better argument for a more basal position along
the path to powered flight, than an argument that they weren't aerodynamic
lifting surfaces. Especially if it is older than Archaeopteryx.
> Contour feathers form aerodynamic surfaces, in the sense of
> streamlining; I think it's perfectly plausible to suggest
> that a small
> theropod with the feather pattern observed in this case
> derived benefit
> from streamlining but not from exerting force through
> interacting with the air.
I don't know about that, the feathers look too long to essentially be keratin
fairings..... and of course, no running birds do this now, and the arms would
need no such fairing, if they could just be tucked away.
> (Or it benefited from a cryptic shape, or
> being able to make a
> particular display in breeding season, or being able to
> look big, or bug
> snaggers, or snowshoes, or something of that character as
Well, tail feathers forming a horizontal plane suggest an aerodynamic function
to me, but this need not mean it glides or flies, I can also see how lifting a
feathered tail could be a sort of display.
There is just something about the shape, in conjunction with planes on the legs
and arms, that to me suggests they work in concert to form stable, controllable
aerodynamic lifting surfaces.
> flightless ducks will do the run-across-the-water thing,
with the wings providing thrust,
Hmm interesting, I didn't even know there were flightless ducks.