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RE: Sneak Peak at Yale Torosaurus Sculpture
> -----Original Message-----
> From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of
> Dino Guy Ralph
> Sent: Tuesday, September 27, 2005 12:30 PM
> To: email@example.com; firstname.lastname@example.org
> Subject: Re: Sneak Peak at Yale Torosaurus Sculpture
> You want cheeks? Check out the cheeky hornbill hatchlings at
> http://avesinternational.com/softbillnurs.html .
> Lots more cheeky than Parsons' _Leptoceratops_ illustration at
> http://www.ohiou.edu/news/pix/LEPTOCERATOPS_2.JPG .
Not sure I see the cheeks on the hornbill hatchlings. . .a little fleshy bit
at the back, I guess. . .
And some aspects of the Leptoceratops illustration are a little odd to me.
But that's for another time. . .
> Furthermore, ceratopsians had immense, powerful jaw muscles and teeth
> adapted for chopping up tough plant material in the manner of oversize
> shears. I would think that these shearing tooth batteries (even more than
> grinding tooth batteries) would require accessory cheeks, as otherwise
> of the processed food material would be shorn off by the jaws along the
> occlusal cutting edges of the teeth, and without retaining cheeks, the cut
> off material would drop to the ground. Would you use a Vegimatic without
> cover? ;^)
Many of those animals without cheeks have incredibly powerful jaw muscles.
For instance, a turtle skull is essentially a (tiny) brain with a beak and a
big bony scaffolding for jaw muscles. Likewise, extremely big jaw muscles
show up in the ceratopsian lineage well before the development of the tooth
> Moreover (as Dr. Tom has noted) the teeth are laterally recessed within
> skull, as in cheeked herbivorous mammals, and most unlike extant
> reptiles, which aren't adapted for oral processing to the extent we see in
This recess isn't that prominent at the front of the jaw. Undoubtedly, not
all of the teeth were exposed; e.g., the posterior-most maxillary teeth
would have been covered in life by the coronoid process of the jaw. Would
this indicate something about the feeding mode?
> Cheekless ceratopsians? I wouldn't be so sure about that.
I'm not certain either way--I'm fairly agnostic on the issue at present,
perhaps leaning a little in the "cheekless" direction. Mainly, it's just fun
to play devil's advocate. ;-) Paleontology never gets anywhere unless we
question these old "truths"! (in a scientifically testable way of course. .