[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Archie skull pneumatics?

Nick Gardner (ratites637@hotmail.com) wrote:

<Are you saying there were no teeth preserved, or no teeth whatsoever?>

  No teeth were preserved was my statement, rather than the jaws being
edentulous naturally. Incidentally, the term edentulous is used in
mammology to mean a jaw that has no teeth, rather than a jaw that lacks
any form of teeth naturally, and can refer to a jaw that has empty tooth
sockets, and so it is edentulous in many examples. However, both Rutger
Jansma and Luc Bailly sent me photos of a blown of figure that I had that
was in much more clear detail than the ones I already had, and show, on
the positive slab, the presence of a small, triangular, oblate crown-like
object that is indeed tooth shaped and appears to be lower than
mesiodistally long and expanded at the base. Unlike ion *Epidendrosaurus*,
the "tooth" occurs at the rear of the dentary, and may be a putative
difference between the two.

  Simialrly, Rutger states that the photos of the type *Epidendrosaurus*
jaw show several fossae that allude to only seven teeth, and I would like
to make a sharp note on this: the positive slab is deeply emarginated and
the low-angled--lit photograph obscures the internal features of the
impression of the conjoined dentaries ... it is not possible to confirm
nor deny the identifications of Zhang and Zhou in the paper on tooth count
or morphology based on observation. I suggest asking for better photos
too, these are rather grainy and of poorer quality than those in the
Czerckas volume.

  -- On the same mein, as for *Sinosauropteryx* teeth, they are
constricted at the base, where the crown posteriorly forms a triangular
section that curves posteriorly into the distal carina, and this can be
considered a form of constriction. Mickey Mortimer should know better than
citing taxon matrices as sources of positive data ... they are present to
test, not follow absently.


Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.