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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
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>                  
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>                          http://www.scienceblogs.de/hier-wohnen-drachen


Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
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Mailing Address:        Thomas R. Holtz, Jr.
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