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Fibers and Manus of <Compsognathus prima>/<Sinosauropteryx prima>



I would like to post some questions to the group in order that I may
formulate some tentative conclusions about paleontology's latest puzzle,
<Sinosauropteryx> (or <Compsognathus>, as the case may be).  I know that
any such conclusions would be a bit premature, but I see no reason why we
can't put a few more facts into the mix to help us sort out this enigmatic
creature.  Naturally, I anxiously anticipate further fossil preparation,
more thorough examination, and published articles on these specimens. 
Until then, I figure that this forum is the best we can do. 

QUESTION #1:  Supposing the fibers along <Sinosauropteryx's> back supported
a crest in the living animal, what related animals, living or extinct, have
featured a crest along the top of the head, the back of the spine, and the
underside of the tail (and, possibly, under the throat and elsewhere)?  As
I understand it, the midline frills depicted on Mosasaurs and on Osborne's
Anatosaur have since been considered erroneous.  On the other hand,
Diplodocids, Kritosaurs, and Ceratosaurs have been shown to have robust
spiky or knobby dorsal elements, most unlike iguanas.  Also at issue is the
taphonomy of midline frills in extinct species.  Do we have any fossils
which show frills, and if so, did they break up into patches as the fibers
did in <Sinosauropteryx>?  Speculation can be fun, but what I'm looking for
here is evidence.  

QUESTION #2:  Supposing the fibers along <Sinosauropteryx's> back extended
above the surface, what could we expect them to look like in the living
animal?  Would the fibers be similar <in appearance> to coarse or fine
hairs?  Dense or sparse?  Covering most of the body (as one would expect
for insulation), or appearing only in isolated regions?  How do the fibers
compare with those believed to be visible in the <Sordes> and
<Pelicanimimus> specimens?  Speaking again of taphonomy, does the pattern
of patchy fibers compare to that seen in fossil specimens of birds or
mammals?  Are the midline fibers missing from one fossil slab evident on
the counterslab or were they removed prior to burial?  Or were the
"missing" fibers never there on the living animal?  And just how would we
expect these fibers to appear, based on our knowledge of related animals?

QUESTION #3:  The Dream Team that went to China to view <Sinosauropteryx>
(including John H. Ostrom, noted authority on <Compsognathus longipes>),
concluded that it may be proper to assign this animal to the genus
<Compsognathus>.  That being the case, I was wondering if anyone has been
able to establish the digital configuration of the manus (or hand) of the
Chinese specimens.  The phalanges appear not to be so scattered as those of
the <Compsognathus longipes> type specimen, which leads me to wonder: Does
the Chinese theropod have two fingers on its hand or three?  I have, of
course, seen Michael Skrepnick's illustration, which distinctly shows three
functional digits per manus.  And no, I will not base my ultimate
conclusion on the <Compys> on view in "The Lost World."  ;v) 

OK, I've done it now.  Time to duck and cover! 

-- Ralph Miller III  gbabcock@best.com