re: Wilkinson's new pterosaur paper

[david peters <davidrpeters@earthlink.net>]

I don't THINK this has been mentioned on DML yet...

Matthew T. Wilkinson, "Sailing the skies: the improbable aeronautical success 
of the pterosaurs," Journal of Experimental Biology v. 210 (2007), pp. 
1663-1671. (The cover photo of the issue-- linked to a different article-- is a 
very cute fruitbat surrounded by yellow flowers.)

I skimmed it very quickly. Reports on a variety of research, including 
aerodynamic theory and wind-tunnel experiments with models of pterosaur wings. 
The simplest model-- a flexible sail on a foelimb/finger mast-- would be quite 
astonishingly inefficient, aerodynamicswise. Author plumps for a more complex 
model, in which the outer, narrowing, part of the span is stiffened by 
actinofibils and the inboard section of the wing (which he assumes extends down 
to attach fairly far down the hindlimb) is more flexible: it could be 
controlled (tension increases/decreased as needed?) by hindlimb movements, and 
its aerodynamics greatly aided by the effects of a propatagium (supported by a 
mobile pteroid bone) that could be varied in angle and area. ... It's billed as 
a review, so covering a lot or research and maybe integrating it.


Allen Hazen
Philosophy Department
University of Melbourne

>>>

I understand from one of the higher ranking pterosaur workers that after 
Wilkinson made his speech from the podium on the same subject (see above) at 
the last SVP meeting he was academically thrashed by Chris Bennett on wing 
shape, pteroid orientation, etc. I applaud Chris on this matter. I heard that 
Matt took it well. 

Once again, if someone can: 

1) produce evidence that the pteroid fits in the cup of the preaxial carpal 
when the current evidence shows this to be the nesting site of a sesamoid, 

2) produce a phylogeny that produces such a weird connection when the current 
evidence shows the preaxial carpal and the pteroid have side-by-side location 
precedents in all taxa between pterosaurs and Cosesaurus and that these two 
preaxial bones are migrated centralia, 

3) show how this contraption works with tiny anurognathid pteroids as well as 
giant needle-sharp nyctosaur pteroids, 

4) produce evidence of a deep chord wing membrane when all the current evidence 
indicates one stretched between elbow and wing finger, 

5) produce a flying model that employs such a configuration, when all such 
attempts have crash landed, 

then all Bramwell & Whitfield > Wilkinson aerodynamic studies will merit study. 
Until then, doggoneit, why bother? 

Will someone please produce a report on the aerodynamics of the Zittel wing? 
It's real.

David Peters
St. Louis