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Re: Nice example of narrow chord pterosaur wing on the 'net



David M. wrote:

Not sure how it can be interpreted at all, blurry as it is. Some moron 
DESCREENED it -- yes, I am shouting. It makes my eyes hurt; I try to focus, but 
there is no sharp image to focus on! So, I can't tell if that's a wing membrane 
or just the limit of preparation (as it is around the tail). Most importantly, 
the part of the wing proximal to the elbow isn't visible.

M. Habib wrote:

I echo David M. on this one - the photo is not of sufficient quality to make a 
good judgement. Furthermore, most current debate regarding pterosaur wing shape 
centers on the issue of wing *attachment* - since the inboard wing cannot be 
seen (unprepped or simply missing) there is no way to use the specimen in 
question to address that primary aspect of the debate. It is very nice 
Pterodactylus, though.

Jaime H. wrote:

  If I were to take that fossil at face value and assume the wing as preserved 
would have been precisely that in life, I would assume that the patagium would 
only extend just beyond the first knuckle of the wing finger and no further. 
This would not be evidence of a narrow-chord wing, but rather of a no-chord 
wing; a non-wing, as it were. This is unlikely to be the case, I think, based 
on preservation of apparent flgiht-related adaptations in what has been 
contended as a juvenile fossil, such that the integument should therefore be 
assume to be incompletely preserved.

>>>

1. To DM: Descreened? I don't think so. That would indicate publishing 
(halftone dots) first then uploading to the net. Other photos from the same 
collection are distant, out-of-focus, etc. This person simply did not have a 
tripod. Even so, not bad. Makes your eyes hurt? LOL. Cute. Part of the wing 
proximal to the elbow missing? Well, to my eyes it looks like it went beneath 
the surface of the matrix originally and was prepped away. Or they didn't go 
deep enough (less likely). Here one simply takes the >trajectory< of what data 
you do have and continue it in the same curve, which runs right about at the 
edge of the prepping (sad) until the prepping ends and -- voilá! --there is a 
line of something leading to a point 2/3 down the femur, exactly as shown in 
the Vienna specimen, Bennett's "Anurognathus", etc. Maybe you didn't see that?  
There it is. Someday we may find the perfect pterosaur. Unfortunately, it's not 
today.

Okay, erase that. Let's assume that all other pterosaurs have a wing membrane 
that connects to digit V, or mid thigh. Well, unfortunately here there is no > 
evidence< for this -- not in this pterosaur anyway  -- come to think of it, not 
in >any< pterosaur. Granted, lack of evidence is not always evidence. So, if 
you >have< evidence, let it be known. It's that easy.

2. to MH: Okay, well, Pittsburgh SVP is coming. Let's put this specimen on our 
list. And let's check out that anterior thigh together.

3. to JH:Umm, you don't >see< the brachiopatagium extending apparently in front 
of the wing (in this case ventral) to the proximal quarter of the fourth wing 
phalanx whereupon it flips over to the posterior (in this case dorsal-ish) 
margin continuing to the tip (where it needs a wee bit more prepping)? Jaime, 
as the Vienna specimen shows, the wing essentially disappears when folded, but 
only to this extent. Take another look if you will, Maybe bring it home to 
Photoshop and place it under Image > Adjustment > Levels > Auto. That will 
extend the gamut of colors for easier viewing. 

Summary: I add this to my list of narrow-chord wing membrane examples (some 
good, some not so good). And I remain eager to see a single example from the 
opposing camp. 

David Peters
St. Louis