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Re: [jonest@ava.bcc.orst.edu: Re: [n9435712@henson.cc.wwu.edu: A curious contradiction regarding RT]]



By some miracle I was actually able to *locate* the my copy of the
issue of _Science_ containing the Ruben et alii article.  Rereading
it I remembered why I had found it unconvincing the first time (see
below).

From: jonest@ava.bcc.orst.edu (Terry D. Jones)
 >   Subject: Re: [A curious contradiction regarding RT]
 > 
 >   ... thus leaving the impression
 >   that it showed evidence of RTs.  It does not.  There is clear
 >   indication that, in life, the animal possessed ethmo- or OLFACTORY
 >   turbinates only.  There is not the slightest indication that RTs
 >   might have been present! I remind readers that olfactory turbinates
 >   occur in ALL amniotes, whether ecto- or endothermic.  ...

While I am willing to conceed that the turbinate supports actually found
in the nodosaurid skull were olfactory, not respiratory, I think the
skull still brings up an issue with the analysis.

As I remember the nodosaur article (?in SVP??), the data showed large,
complex, nasal passages.  Thus, to the extent that Ruben et alii are
arguing that dinosaurs lacked RT's based on the *size* of the nasal
passages, this skull *does* weaken their argument.  That is, even in
the absence of direct evidence for RT's in the nodosaur, the volume
available seems to have been quite adequate for their presence.
(Unfortunately, unless somebody can remember the reference I would be
hard put to relocate that article, as it is even older than Ruben
et alii).

And, indeed, this touches on my original reason for being skeptical
of the results: they only included *three* dinosaurs, and two of
*those* were coelurosaurs, and the third was a highly specialized
hadrosaur.  I would have much prefered to see examples from all major
dinosaur lineages, including a less specialized member of the ornithopod
lineage (say _Iguanodon_ or some basal hadrosaur).


As mentioned in another article, I am in the process of cross-
referencing their support for an RT-endothermy relationship.  I
may be done in a week or two. (I am not sure that the local research
library will be open this Sunday, as the school season may not have
started yet).

swf@elsegundoca.ncr.com         sarima@ix.netcom.com

The peace of God be with you.