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RE: Flight capablities of Archie & Confucius? Not so good...

  While my argument does not assume the work of Nudds and Dyke (1994, 2007, and 
2010) -- assessing the wing anatomy, wing-stroke reconstruction, and 
feather-shaft extrapolation respectively -- is correct, it is made in the 
perspective of a scientific argument that can be tested, but makes predictive 
statements. The supplemental information, for example, desires to test the 
cortical thickness of shaft walls, but cannot, so it adopts cylindrical 
thickness where the shaft is perfectly round. We can test this, for example, by 
arguing a few things:

  1) Preservation in lagerstatten correctly preserve rachis shaft width; and

  2) Construction of the rachis width differs from that of living birds.

  This is not to say that Nudds and Dyke are right, but even the dissent should 
be cautious. Modelling as it works in living birds should be the primary method 
by which the fossil forms are compared, especially when the animals are implied 
to have a behavior that, since 1876, has been projected as being comparable to 
living avian performance.


Jaime A. Headden
The Bite Stuff (site v2)

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 

> Date: Fri, 14 May 2010 09:26:47 -0400
> To: qi_leong@hotmail.com; david.marjanovic@gmx.at; 
> Dinosaur.Mailing.List@listproc.usc.edu
> From: jeff@jeffhecht.com
> Subject: RE: Flight capablities of Archie & Confucius? Not so good...
> Some caution would be wise in interpreting Nudds and Dyke's results. 
> Science's own news story quotes cautions from both Luis Chiappe and Phil 
> Currie.
> http://news.sciencemag.org/sciencenow/2010/05/did-first-feathers-prevent-early.html?etoc
> Chiappe makes an important point in warning that feather shafts in fossil 
> bird feathers often are not well defined. It also would have been nice to 
> include weak modern fliers in the comparison with living birds. For that 
> matter, it would have been good to include other fossil birds, either from 
> the Cretaceous of Cenozoic.
> At 4:22 AM -0600 5/14/10, Jaime Headden wrote:
>>David Marjanovic wrote:
>> Enough to notice it, pass it over, and go one with their tact? An 
>> interesting example, perhaps, of using "poor flying ability" as meaning "can 
>> fly, but not as good as wrens." There's a level of relativity here that 
>> hasn't been measured, and as long as the performance output of one is simply 
>> less than the other, one can still hypothesize that the "poor" ability can 
>> enable the behavior one has espoused already. Despite this, Paul's 
>> _Dinosaurs of the Air_ doesn't even cite Nudds and Dyke (1994).
>> One thing that can be said of the paper is that it does better to supplement 
>> the analysis with further data, so now they can both be cited and used to 
>> argue further for lack of powered flying capability, if even passive flying 
>> capability (i.e., "powered" gliding). One thing that cannot be said of it is 
>> that it won't tell paleoartists to NOT draw Archie as a fully powered flier 
>> (much less *Confuciusornis*. It is too sexy of an idea to give up. They have 
>> wings, therefore they must have flown; bird have wings, and birds can fly; 
>> not only do wings = flight, and birds = wings, but wings = flight just like 
>> birds.
>>Nudds, R. L. & Dyke, G. J. 1994. Flight capabilities of *Archaeoptery*. 
>>_Nature_ 370:514.
>>Nudds, R. L. & Dyke, G. J. 2010. Narrow primary feather rachises in 
>>*Confuciusornis* and *Archaeopteryx* suggest poor flight ability. _Science_ 
> --
> Jeff Hecht, science & technology writer
> jeff@jeffhecht.com or jhecht@nasw.org
> 525 Auburn St., Auburndale, MA 02466 USA
> tel. 617-965-3834 http://www.jeffhecht.com
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