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Re: BIRDS



To address a few matters. Since there have never been any trace of ossified
sternal ribs in any Archaeopteryx it is unlikely they existed, the cartilage
version must have been present. Sternal fusion is very irregular in theropods
and Protarchaeopteryx may have been a large juvenile. There is a single
CENTRAL indentation distinct from the more lateral coracoid facets in both on
the anterior edge of both the Protarch and Arch sternum. Elzanowski and I
agreed that the degree of metatarsus cobinding is similar in the two
archaeopterygiforms. There was a well developed postorbital in Archaeopteryx.
It may or may not have contacted th jugal, so this character cannot be scored.
Likewise, there is no complete ascending process of the quadratojugal so its
contact with the squamosal is not certain. There definitely is no evidence for
a palatal propulsion joint in Archaeopteryx, the supposed ventral quadrate
articulation of the pterygoid is actually a weakly developed ectopterygoid
process. Ergo avian cranial kinesis was probably not present. 

GSPaul