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Re: On the Issue of Beaks in Avepectorans (Long)



Jaime... You asked for something showing similar patterns of the foramina 
between the more basal theropods and the later known to be beaked aves. The 
gull and swan that was posted on my website was dismissed by you as being 
nothing but an oddity (But remember Jaime, that Larsus, as well many 
anseriformes, are large birds with correspondingly larger heads more on the 
size of the average small theropod).

Therefore Jaime, I'd like to ask for your opinions about a few things:

http://digimorph.org/specimens/Dinornithiformes/

Now... First I would like to ask you to respond on several issues about these 
*Dinornis* movies.

1. About the lateral row on the dentary... Are they reptile-like or 
theropod-like in your eyes? Describe why in either case.

2. About the medial aspect of the dentary... Do you see a row of foramina here? 
Do you believe if there is a row, that it should be dismissed as was done so by 
you with the swan?

3. http://hometown.aol.com/drlectervv/Various2.html

Do you believe by the evidence given, that the numerous sequential foramina are 
not only for the hyolingual musculature, but for said muscles alone? Are there 
sequential foramina located on the upper medial aspect of the dentary that have 
the sole purpose of innervating hyolingual musculature?

Do you believe if there are sensory branches as well as anastomes here between 
the mandibular branch of the trigeminal and the 7th, 9th hypoglossal and first 
cervical, that this negates the foramina row shown as being in any way 
homologous to the foramina row for the alveolar in normally toothed regions of 
theropods?

If yes, explain why please.

If no, explain how medial rows of foramina then correlate to a non-fused 
keratinous covering.

4. Also, crocs have a keratinous covering where their teeth protrude through 
and also have a medial row of foramen. Do these rows in crocs differ in a way 
that can show they are not homologous to:

a. The same rows seen in toothed theropods?

OR

b. The row shown medially on the swan mandible shown at given address above?

And also about crocs... Jaime, you said that only "modern" crocodilians have 
the extensive pitting for facial âtactileâ surfaces. Is Sues et. al. in JVP 
V. 16, n. 1, pg. 35 (paragraph with the skull highlighted) saying that 
*Protosuchus micmac* had foramina and pitting like modern crocodilians or not? 
(also, *Calsoyasuchus*, JVP 22, n. 3, pg. 593-611.)

5. Do you see any medial row(s) on the upper jaw in the Moa? If no, please tell 
me what you believe it is that I might have perceived.

If yes, do you believe there is a chance that these foramina in any way 
innervate and intrinsic, extrinsic, or external hyolingual musculature?

If yes, please explain this phenomenon. If no, please state both the purpose of 
these rows and if they are or are not homologous to the corresponding rows seen 
on the dentaries.

If you believe the foramina rows on the medial aspect of the lower jaw are the 
corresponding rows to the similar looking ones on the upper jaw, would this not 
mean that their purpose would not be first on the lower jaw to innervate the 
hyolingual muscles since it is doubtful that the corresponding regions on the 
upper innervate them at all?

Do you believe these top rows, if there, are or are not homologous to the rows 
of foramina found on the upper jaw in toothed theropods?

Would it be truthful to say that in toothed animals, branches from V2 (upper) 
and V3 (lower) innervate alveolar regions on (in) the jaws and any sensory 
feedback anastomosis present between V3 and other cranial nerves (and first 
cervical included for sake of argument) are secondary in nature?

Now... If you agree in any case that these rows are homologous to the same rows 
found in toothed theropods, would it not be logical to assume the rows on the 
dentaries are also homologous to the ones found on toothed theropods?

Finally... Can any conclusions be drawn on correlating such rows of foramina, 
if present, with toothed animals alone? If so, what are they?

These questions are not just limited to Jaime... All opinions are welcomed and 
very much encourged.

Thanks.
Kris