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Re: Coracoid/scapula (was Re: flying Archie)

It would require two more reversals -- in *Sapeornis* and in
Confuciusornithidae. Four reversals instead of two or maybe three

The condition is unknown in _Sapeornis_ and confuciusornithids because the
suturing/fusion obliterates the nature of the articulation. Thus, they
could have evolved from birds with the enantiornithean-style peg-and-socket
articulation, and the immobile joint could be secondary. Under this
scenario, the condition in _Sapeornis_ and confuciusornithids is not a
reversal. It would be (and has been) coded as '?'.

Ah, then we aren't talking of exactly the same character. I am talking of the joint, which I interpret as having 3 possible states: flat (plesiomorphic), coracoid in scapula, or scapula in coracoid. I may be wrong in which of these is the plesiomorphy, but the reversals I mentioned all require independent losses of the joint.

Neornithes never lose the joint, BTW, unless they lose the ability to fly.