[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Fwd: Re: The Eternal Question: Lips or Skin?
Jon Wagner asks me to forward this to the list:
--- kritosaurus <firstname.lastname@example.org> wrote:
> Reply-to: "kritosaurus" <email@example.com>
> From: "kritosaurus" <firstname.lastname@example.org>
> To: <email@example.com>
> Subject: Re: The Eternal Question: Lips or Skin?
> Date: Wed, 8 Aug 2001 10:56:34 -0500
> Jaime, please forward this reply to the list.
> Jaime wrote:
> >Mike Hanson seems to adamantly state that they do, for one reason,
> >apparently: maxillary and dentary mental foramina. These are
> >extensive in other reptiles (those that hd legs, anyway), but this
> >issue of lips in lizards is not the same as for mammals.
> >[...] Reptiles have extensive gums, mind, and lizards lack lips in
> >the mammalian sense. In this way, they resemble other reptiles in
> >having a tendonous band of tissue that wraps around the oral
> >with some very few muscles attaching to the margins ... the they
> >there to hide the teeth only. They are not conventional "lips"
> a) As Mark Hallett points out, I doubt very much that lizard
> lips ONLY
> "hide the teeth." My little Pogona vitticeps seals his mouth up
> nicely with his lips... his teeth are so small they don't need to
> be hidden
> b) One thing often forgotten: EVOLUTION HAPPENS. It is entirely
> conceivable that the lips of lizards and mammals may be homologs,
> with the
> lips of mammals being substantially derived from the common
> ancestral form.
> c) With all respect to Dr. Holtz's turf: WAIT FOR THE PAPER!
> seeing Dr. Witmer et al.'s full battery of evidence, all of this is
> speculative, and somewhat inappropriate (in my opinion). No more
> inappropriate than the wholesale adoption of the "Witmer Group
> reconstruction" by some paleo-artists, mind you...
> >The nerves that exit the foramina (the maxillary
> >branch of the maxillopharyngeal nerve) are strictly involved with
> So that we are clear, the best interpretation I have seen is
> that the
> neurovasculature package which exits via the foramena on the
> "labial" margin
> of the dinosaurian maxilla appears to be associated with the
> branch of the trigiminal nerve.
> Jonathan R. Wagner
> 9617 Great Hills Trail #1414
> Austin, TX 78759
I stand chastized about which nerve ennervates the maxilla (also
noting that Waylon Rowley used the same nerver, trigeminal)...
Jaime A. Headden
Where the Wind Comes Sweeping Down the Pampas!!!!
Do You Yahoo!?
Make international calls for as low as $.04/minute with Yahoo! Messenger