Re: Dinosaur beaks

[David Marjanovic <david.marjanovic@gmx.at>]

> I've asked for and searched for any evidence against the presence of a 
> beak of one form or another, even if it's just a horny covering. [...] 
> I have neither found nor received any answers. What that means? 
 
That I didn't get the idea of looking at a photo of *Eoenantiornis*. :-( 
In that specimen feathers reach almost to the tip of the snout, they even 
cover half of the premaxilla. There are none at the very tip, but maybe 
they were prepared away to reveal the teeth, or maybe the matrix above 
them was not prepared away, to keep the contrast between a ?white polished 
matrix and the teeth, especially in a black-&-white photo. 
 
The photo in Mesozoic Birds (p. 257) is different from the one in the 
original paper. In the former the tip of the dentary is prepared, and the 
tip of the snout lies in a polished groove. In the latter there's a tiny 
dark patch right at the tip of the premaxilla, the same shade of gray as 
the feathers, but it's only a few tens of pixels in size, because 
Vertebrata PalAsiatica has small pages and low-resolution photos, so I 
can't tell if it's any real feature. It does look striated, like a couple 
of cut feather bases. I could try to scan it, but the resolution can't get 
better... 
 
Your last post implied that the alternative to a beak is scaly skin like 
on a foot. I think the alternative to a beak in a coelurosaur is feathered 
skin like in the rest of the head.  

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