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Re: Crocodilian vs Avian looks



Before I forget, someone wanted a scan of plate 2 of the *Protoavis*
paper... who? :-]
"Details On" forthcoming!

> > Well, AFAIK these grooves look damn like the ones on mammal skulls that
> > really contain blood vessels and nerves for the lips. Cheeks in
> > ornithischians are inferred the same way.
> >
> > Did segnosaurs have cheeks? And prosauropods?
>
> With regard to this debate, may I draw your collective attentions to this
> old BBC news article?
>
> http://news.bbc.co.uk/hi/english/sci/tech/newsid_184000/184387.stm

>From that article:

"But Mr Witmer's studies have found this comparison to be false. Modern
mammals with muscular cheeks do not have the same sort of excavated area on
their lower and upper jaw that is found in dinosaur fossils."

Due respect to Mr. Witmer (and his works on cranial pneumaticity), but the
restoration of a protoceratopsian without cheeks looks very awkward, because
these animals chewed and would have needed to prevent the food from falling
out. I can't buy it. I wouldn't expect exact identity to mammalian cheeks
(and lips) anyway, because we're talking of convergences...

"A more likely conclusion is that these jaw features supported an extended
beak, similar to the beaks on eagles or crocodiles."

Crocodiles have beaks? Interesting... Very interesting... B-)

So I repeat my question:
> > Did segnosaurs have cheeks? And prosauropods?