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Re: Sinosauropteryx






>
>Several questions were proposed earlier today regarding 
Sinosauropteryx.
>I can try to answer then, but I have NOT seen the SVP abstract (Geist,
>et al). However, J. Ruben did prepare a dissection of the tail of a sea
>snake which is flattened dorso/ventrally. The color photos that I saw
>contain fibrous material, which are most likely collagen.
>   The presence of collagen in this tissue is no suprise. The basic 
origin
> is mesodermal and collagen is the support tissue involved. There are
>differences in the density of the fibers in the 2 tissues, but that is
>probably not significant. There is, in fact, a simple way to resolve 
this.
>All that need be done is to measure the fiber diameter in the 
Sinosauropteryx
>material. Keratin and Collagen differ in the fiber diameter, and this 
can
>probably be done with the material now available. The lab in Nanjing is
>familiar with the thin section techniques and have both TEM and SEM 
scopes
>on the campus.I suggested to Chen Pei-ji that preciesly this be done.
>   While we were in China Larry Martin also came up with the 
observation
>that Sinosauropteryx might have been semi-acquatic. Perhaps presuing 
prey
>into shallow water etc. The flattened tail, or a rod-like tail with a
>frill might have been an aid to moving. Like one might use an oar to 
move
>a small boat. Could be, who knows?
>   I don't know exactly what all Geist et al, have actually seen in 
terms
>of material. Photos as we all know can be misleading. I'd say go to his
>talk and find out.
>   I don't have an easy answer for why integument (or any other tissue)
> fossilizes in any one particular way. Certainly the posture of the 
beast is
>important and each of the Sinosaurpoteryx seems to reside on its side.
>
>    In my experience all extant birds, and I've looked at a lot of 
them, have
> feathers that with a tiny bit of careful looking can be identified as
> such. Eye lashes and facial bristles are very hair-like, but always 
have
> barbs at the base. Filoplumes, on the other hand, are extemely 
abundant on
> most birds. For a great proportion of their length, they lack barbs. 
But
> they are always present on the tips. There are other examples of 
specialized
> feathers--usually involved in displays--that lack barbs over some of
> their length.
>     The plumage of young penguins (despite their appearance in photo)
>  consists of very dense down feathers. Same for the neck of the 
Ostrich.
> This stuff feels like felt or soft material, but is feathers and 
feathers
> only.Ralph Miller is exactly right "eyeballing a glossy magazine image 
cannot
>compare with viewing the  actual feathers under magnification."
>    BTW, many of the feathers in the plumage of adult penguins have 
fused barbs
>which give then a scale-like appearance. But they too are feathers 
(made of
>the feather protein, not scale-sized molecules).
>
>                           Cheers,
>                                     Alan
>


 Good points. And I think that the Sinosauropteryx feathers are 
feathers. Geist and the Oregon State team are *always* full of shit ( 
pardon my french.  )  I just don't want to see Fedducia's reply to this 
issue.

 By the way my vote for the name of Rigby's tyrannosaur (if it is new) : 
 
 Tyrannosaurus mex ,   a la Far Side  (-:

 WMattTroutman

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