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Coelophysoid-Protoavis connection?



I've read some posts on the list about the possible relationship between Protoavis and the Troodontidae. Currie says that the braincase and middle ear appear remarkably alike for animals separated by such a very long time. In The Dinosauria (Weishampel et. al. 1990, page 156), the tympanic cavity of the coelophysoid braincase is described as "....deeply recessed beneath the paroccipital process and is divided into a separate rostral and caudal chamber by a delicate oblique septum...." in the same work (page 262), the middle ear of Troodon formosus is also described as recessed beneath the paroccipital process and subdivided by a ridge. In The Complete Dinosaur (Farlow & Brett-Surmam 1997, page 231) the skull of Protoavis is partially reconstructed. The orbits are huge and the bones don't appear to have interdigitated or have been well-sutured. To me, it looks like a juvenile. So, is it possible that Protoavis is a baby coelophysoid with a non-ossified jugal-postorbital bar and a middle ear convergent with those of the Troodontidae? It seems like a more parsimonious explanation for such an ancient animal.
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