GALLIFORM DAY

["Matthew Troutman" <m_troutman@hotmail.com>]

TURKEY DAY

     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 
"ball".
2)  Quadrate process for origin of m. adductor mandibulae externus 
3)  Quadrate with two mandibular condyles seperated by an intercondylar 
sulcus.
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".  ;-)

Matt Troutman 
m_troutman@hotmail.com


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