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RE: Senter 2006, Confuciusornis, and humeral mobility



  These birds do not suffer the unfortunate condition of having evolved in and 
around the point where flapping flight was being developed, including the 
absence of an alula (for landing controls) or even a developed retricial fan, 
much less a perching foot. These birds are (or were) either terrestrial or 
uncomfortably semi-arboreal. If the latter, the development of a means of 
controlling attitude and rate of descent (as well as projection during aerial 
travel) would be almost certainly more important than forms of steady flight 
controls. If so, the quality of marine birds who spend most of their lives on 
the wing, and have adaptations other extant birds lack to enable this, is 
almost certainly irrelevant.

  Let me pose this question: What other bird (extant) lived in an inland, 
lacustrine, and forested environment, and had extremely high aspect, tapered 
wings? We'll ignore the issue of diet for now. 

Cheers,

Jaime A. Headden
The Bite Stuff (site v2)
http://qilong.wordpress.com/

"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 
Backs)





----------------------------------------
> Date: Fri, 25 Mar 2011 23:40:45 -0400
> From: jaseb@amnh.org
> To: MHabib@Chatham.edu
> CC: jaseb@amnh.org; dinosaur@usc.edu
> Subject: Re: Senter 2006, Confuciusornis, and humeral mobility
>
> Michael Habib has written to the dml this week:
>
>
> > I actually was not doing a launch calculation with regards to the limits
> > of flapping, as I was under the impression that we were considering the
> > generation of sufficient circulation during steady flight.
>
> and today:
>
> > The main problem, however, continues to be the climb out
> > issue. The steady flight stroke angles are not applicable to phases of
> > sharply accelerating flight, especially when climbing after launch.
>
>
>
> So let's just stick to your original suggestion that we just consider
> steady flight for now. We know that there are many modern birds, such as
> Shearwaters (http://www.youtube.com/watch?v=Cjmtt_B_i4A) and condors, that
> have great difficulty getting airborne yet they may still live much of
> their lives on the wing.
>
>
> Jason Brougham
> Senior Principal Preparator
> Department of Exhibition
> American Museum of Natural History
> 81st Street at Central Park West
> 212 496 3544
> jaseb@amnh.org
>