Re: A therizinosauroid dinosaur with integumentary structur

[<TWILLIAMS@canr1.cag.uconn.edu>]

Ralph W. Miller III wrote:

> The Yixian formation and the Solnhofen limestones represent distinct
> depositional environments.  I do not believe that it is fair to assume
> that _Compsognathus_ had no filamentous integument just because there is
> no strong fossil evidence of filaments on the two known specimens. 

But _Archaeopteryx_ of Solnhofen shows feathers.  Are feathers more 
likely to be preserved (as imprints) than their bristle-like 
homologs/precursors?  

As you say, we just don't know if _Compsognathus_ had a filamentous 
body covering.  I'm saying that just because _Sinosauropteryx_ had 
one, it doesn't necessarily mean _Compsognathus_ did too.  It's not 
the same thing as the tridactyl vs didactyl manus.  Compy probably 
had a tridactyl manus.


Tim

> Just as paleontologists
> have deduced that _Compsognathus_ most likely had three digits per manus
> (hand) as _Sinosauropteryx_ did -- in spite of the fact that many of the
> manual elements are missing from the _Compsognathus_ specimens and prior
> restorations often featured a didactyl manus -- so, too, there is good
> reason to believe that _Compsognathus_ may have sported a filamentous
> integument, because its nearest known relative, _Sinosauropteryx_, did.
> This hypothesis may turn out to be wrong, but there is no proof that
> _Compsognathus_ lacked a filamentous integument.
> 
> 
> -- Ralph W. Miller III       gbabcock@best.com
> 
> 
>