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Re: The origin of flight: from the water up
James Cunningham <email@example.com> wrote, regarding Waylon Rowley's
<Does stubby translate as 'short', or as low aspect ratio?>
I beleive the use, as applied to some game fowl and many small passerine
birds including dippers, is in both a combination of a low aspect ratio
and the lack of a pennate taper in the wing, so that the wing is rounded.
This shape is a maneuvering feature for birds that possess it. Birds
that use their wings to swim typically, as in auklets and penguins, have
strongly tapered but low aspect wings. This reduces drag while retaining
flight performance underwater. Auklets use this feature both in air and in
the water quite well. I'll talk about Archie in this aspect in reply to
David's post on the recapitualtion of Ebel's theory and his modification
of it (which I highly value, btw -- there was never an intent to discredit
the effort to which David is bulldogging Ebel, as he is developing the
theory in ways that Ebel did not).
As for *Rahonavis* later, it lacks preserved feathers and nor are the
Maeverano sediments conducive to preserving such, so aspect ratio is not
attainable for this taxon ... the body wing and the feathered wing can be
two different things, as can be seen compared to similar armed birds like
the falconids and the accipitrids, which has distinctly different
wing-shapes from each other, given that the arm-shapes are similar.
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps
in the face of adversity, that a simple skip is so hard to do. We should all
learn to walk soft, walk small, see the world around us rather than zoom by it.
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