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Re: Yonghesuchus, was Shuvosaurus
Earlier I wrote:
The Proterochampsidae lies outside of whatever is left of the
Archosauriformes. You'll find they nest in a continuum from Youngina -
Choristodera - Proterochampsidae - Doswellia - Parasuchia.
D. Marjanovic wrote:
That's a very strange assemblage.
>>>> Strange only because it hasn't been TRIED before. Lay them out on paper.
>>>> It'll make sense.
DM: Are you sure you've included all proposed
apomorphies of Archosauriformes as characters in your analysis?
>>>>> Not necessary, as explained way earlier. Taxon inclusion is all that is
>>>>> necessary after 150 or so characters are used. If you're worried about it
>>>>> though, suggest a character or ten that would attract other (traditional)
>>>>> taxa. Would love to see the list. You can choose to keep it private if
>>>>> you wish and I'll respect your request.
DM: Perhaps -- perhaps -- worse yet: if you don't find Lepidosauromorpha and
Archosauromorpha as sistergroups to the exclusion of *Youngina*, then you need
to postulate that the "diapsid" middle ear evolved twice.
>>>>> In the Diapsida, if is difficult to find any characters that occur in
>>>>> isolation. The homoplasy index is way higher than I've ever seen
>>>>> elsewhere. Although the "diapsid" middle ear is not visible in the great
>>>>> majority of taxa â?? and so did not make my character list â?? if it
>>>>> evolved twice or more then it would join the great majority of characters
>>>>> that also pop up repeatedly.
And if you have good material on Youngina, please point the way~! This is a
taxon that needs more study. Broom's illustrations are not up to modern par.