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

Let me try this again...



A while ago I submitted a post regarding some features of
_Compsognathus_, written in the rather pompous and self-righteous style
that I have come to rue in myself but which, I suppose, is a phase all
college students must go through.

Anyway, for anyone who missed it, the gist was that I thought I could
refute some of Ostrom's conclusions about this animal with a perfunctory
look at a photo of the original specimen.  The post was intended to
spark discussion, but apparently it was, in the end, fairly roundly ignored.

If Mickey is willing to let me rephrase myself, I would now like to take
the more humble tack of throwing out a few questions to you professional
types, some of whom, dare I dream, may have laid eyes on a specimen or
cast at some point or another...

1)  The photo I have of the German specimen (_The Ultimate Dinosaur
Book_, David Lambert, p. 81) appears to show that the dorsal surface of
the left pes and the plantar surface of the right pes are preserved.
That sound reasonable?

2)  Ostrom restores the metatarsus with three parallel metatarsals of
about equal breadth.  In the photo, though, it looks (to me) like
metatarsals II and IV of the left pes are flared proximally and cover the
proximal end of metatarsal III, making the pes look like a tiny
ornithomimosaur foot.  Has anyone else observed this?  Is it just a
feature of the photo (or my imagination :-P )?

3)  Does anyone else agree that Ostrom's interpretation of the
manus is unlikely?  I agree that there are probably only two digits (I
can only find four claws on the slab), but I disagree with his phalangeal
count and metacarpal assignments:

   A)  No other theropod that I know of has a phalangeal count of
2,2,0,0,0.  Of course this in itself does not invalidate Ostrom's
reconstruction, but I *think* I can see five non-ungual manual phalanges
in the slab.  There is a long phalanx and a short phalanx associated with
each manus.  Correct?  There is also, I believe, another small, narrow
bone lying across the right metacarpus.  I would interpret this as a
displaced metacarpal except that there is apparently a claw at the end!  Can
anyone corroborate this?  At any rate, five known phalanges would
indicate a phalangeal count of at least 2,3,0,0,0--like the situation in
other didactyl theropods.

   B)  Ostrom labeled the largest and longest metacarpal as number I and
a somewhat smaller bone as metacarpal II.  Given their positions in the
slab, however, it appears to me at least as likely that they are
reversed, the larger bone being metacarpal II and the smaller one
metacarpal I.  This is far more like the situation in other theropods and
seems more parsimonious to me.  Opinions?  The structure of the larger
metacarpal also makes me think it is probably #II; if you care to hear
about it, I can explain another time.

Well, that's about it.  I would appreciate any info anyone out there
could give me, and any questions or comments.  Just e-mail straight to
me, unless you think the whole group would be interested.  And if anyone
has a spare cast of _Compsognathus_ lying around... :-)

Thank you for your time.


Nick Pharris
Pacific Lutheran University
Tacoma, WA 98447
(206)535-8206
PharriNJ@PLU.edu

"It is better to understand a little than to misunderstand a lot."


P.S. Thanks, Ken, for looking out for me. ;-)