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RE: Pachyrhinosaur nasal horn? (was RE: OMEISAUR CLUBS, PACHYRHINOSAUR)
From: email@example.com [mailto:firstname.lastname@example.org]On Behalf Of
Sent: Thursday, May 23, 2002 10:15 AM
Subject: Pachyrhinosaur nasal horn? (was RE: OMEISAUR CLUBS, PACHYRHINOSAUR)
Tracy Ford wrote:
> No specimen that has a boss, not just Pachyrhinosaurus, shows ANY
> evidence of a horn. The Pipestone Creek specimens have both Concave and
> Convex bosses. There are juveniles that have a rudimentary horn (or more
> properly, a split ridge) and at least one specimen that has both a
> ridge and the starting of a boss.
I'm not sure I follow this argument. The rationale behind the possible
presence of a pachyrhinosaur nasal horn is that the boss formed the base for
a large keratinous horn on the snout - analogous to the nasal horn(s) of the
rhinoceros. It don't see how the shape of the dorsal surface (whether it
was concave or convex) really matters. Also, as a cornified structure, we
would not expect the horn to be fossilized as readily as the underlying
I've had this discussion with people for over 10 YEARS now. The comments are
always the same, they don't change. A rhinoceros's horn is keratin, but it's
hair, dinosaurs don't have hair. Dinosaurs have a keratinous horn that
covers and followings the existing skeletal structure.
>> I know Dodson (1996) does not favor this interpretation - why go to all
trouble of transforming the nasal horn just to support a large cornified
horn when the same result (a very large horn) could be achieved by just
modifying the bony horn already there? A good question. However, it
doesn't mean that pachyrhinosaurs didn't do this. Perhaps a cornified nasal
horn held certain advantages over a horn with a bony core.<<
No horn, no horn, NO HORN. It was a BOSS! Why can't people except this? They
had a boss, that's it! Leave the horn off! Darren Tanke has studied (as well
as Scott Sampson) pachyrhinosaurs, they had no HORN!!! I suggest you look at
the specimens and write up what you want after studying the specimens (which
I have done).
Dodson, P. (1996). The horned dinosaurs.
Timothy J. Williams, Ph.D.
> Perhaps a cornified nasal
> horn held certain advantages over a horn with a bony core.
David Marjanovic [email@example.com]
Maybe keratin is cheaper to maintain than bone. Of course this would beg the
question why not all centrosaurines had pure keratin horns...<<
Right, there is no reason for any having a pure keratin horn.
Tracy L. Ford
P. O. Box 1171
Poway Ca 92074