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Ah, Thanksgiving... I hope everybody has a great time stuffing
themselves with _Meleagris gallopavo_. Everybody remember to point out
every single feature of the skeleton (and if you know it, the
musculature) that links this galliform bird to eumaniraptoran dinosaurs.
And try this one: try to find out any *real* characteristics linking
this wonderful bird to any anseriform.
GALLIFORM AND ANSERIFORM RELATIONS
No, no, I'm not going to say that anseriforms are related to
charadriiforms or phoenicopterids, just that they're not related to
galliforms in a close relationship. To all who doubt, read Olson and
Feduccia, 1980. I won't go through a big review of the litt. but enough
of the stuff to get my point through. First of all, the classic Huxley
characters, the parasphenoid-pterygoid and the strong upcurved
retroarticular processes, are totally false. The parasphenoid-pterygoid
articulations have a different development and they really aren't that
similiar, and the retroarticular processes have a different morphology.
Andors (1992) has argued for a close relation of the Galliformes and
Anseriformes based on his interpretations of the diatrymid fossils.
Seven characters, of the skull and mandible, link Galliformes,
Diatrymidae, and Anseriformes.
1) Quadrate otic process with a narrow or obsolete incisure, forming a
2) Quadrate process for origin of m. adductor mandibulae externus
3) Quadrate with two mandibular condyles seperated by an intercondylar
4) Bipartite mandible articular fossa.
5) Retroarticular process of mandible long and upwardly curved.
6) Retroarticular process laterally compressed and bladelike.
Andors' own figures cast doubt on his interpretations. For example
character number 1 is not similiar in galliforms and anseriforms
(including diatrymids); the otic process of the quadrate is exposed
dorsally in galliformes, but not in anseriforms. Character 2 is not
really that similiar; in galliformes the process fuses with the body of
the quadrate or is indistinct from the body of the quadrate. In
character 3 galliforms have a lateral condyle that lies more lateral
than the condition in anseriforms, where the lateral and medial condyle
are very much even. In character 4, the medial cotyle fossa in
anseriforms is seperated into two distinct regions, thus casting doubt
on the homology of the character and usefullness (with a lack of an
appropriate outgroup). I have already discussed character 5 and 6.
Now of course, this is not a comprehensive review of the literature, and
I have not discussed many of the characters of relevance. Also, with a
lack of an appropriate outgroup (and ready study material), this *brief*
*limited* review may well be in error. But hey, I could have loaded a
huge, comprehensive review in your mailboxes for Thanksgiving, so say
"thank you". ;-)
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