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Re: Archaeopteryx feathers and origin of flight based on 11th specimen
I slight asymmetry is functionally no different than symmetry, there is no
positive selection for *symmetry*, either.
And slight asymmetry may help with the maintenance of feather curvature,
with imbrication when the wing is formed, etc.
On Fri, July 4, 2014 3:22 am, Martin Baeker wrote:
>> Yes, the structural spar tends to sit closer to the leading edge
>> than the trailing edge of the wing. The mechanical importance of
>> this for bending and torsional resistance is well understood, and it
>> does not apply if the leading edge is only slightly shorter than the
>> trailing surface.
>
> If this is so, what other advantage does asymmetry have? For if
> there were no advantage to a slightly asymmetric feather, it seems
> difficult to envison the evolutionary path to full asymmetry. (And
> no, I dont accept "display function" as an answer here :-) )
>
> Martin.
>
>
> Priv.-Doz. Dr. Martin Bäker
> Institut für Werkstoffe
> Technische Universität Braunschweig
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> 38106 Braunschweig
> Germany
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> e-mail <martin.baeker@tu-bs.de>
>
> http://www.tu-braunschweig.de/ifw/institut/mitarbeiter/roesler1
> http://www.scienceblogs.de/hier-wohnen-drachen
Thomas R. Holtz, Jr.
Email: tholtz@umd.edu Phone: 301-405-4084
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