RE: Did dinosaur wings evolve for breeding display?

[Tim Williams <tijawi@yahoo.com>]

Jaime is dead right.  There is no concrete evidence that the dorsal appendages 
of _Longisquama_ were paired, or even mobile.  Sharov (1970) followed by others 
(e.g., Haubold and Buffetaut, 1987) reconstructed _Longisquama_ as a gliding 
reptile.  They suggested that these appendages could act as continuous gliding 
surface when spread, and could be folded over the back, in butterfly-like 
fashion, when not in use. 

Voigt et al. (2008) explicitly reject Sharov's interpretation, and claim that: 
(1) there is no evidence for more than one row of appendages in the 
_Longisquama_ type specimen; and (2) even assuming that the appendages were 
paired, they would have performed poorly as airfoil-generating devices.  Voigt 
et al. also reject the hypothesis that the _Longisquama_ appendages were 
homologous to feathers.


Cheers

Tim



--- On Thu, 4/16/09, Jaime Headden <qi_leong@hotmail.com> wrote:

> From: Jaime Headden <qi_leong@hotmail.com>
> Subject: RE: Did dinosaur wings evolve for breeding display?
> To: "Dinosaur Mailing List" <dinosaur@usc.edu>
> Date: Thursday, April 16, 2009, 3:43 PM
> 
>   Not responding to Scott's post, but adding to what
> he said, it should be remembered that right now, there is no
> evidence that the structures on *Longisquama*'s mainslab are
> paired. None of the slabs that preserved only these
> structures showed paired elementals, just a few that were
> skewed and overlapped, but the bases were isolated and not
> overlapping, and were of differing lengths. This argues that
> the structures, if they were part of *Longisquama*'s
> anatomy, were singular and likely on the midline.
> 
>   Cheers,
> 
> Jaime A. Headden
> 
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