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Re: Heilmann and furculas



 
As it is widely known, Gerhard Heilmann reached his conclusion that birds descended from Pseudosuchians largely due to his failure to find clavicles from the remains of theropod dinosaurs. However, I read from Gregory S. Paul's Predatory Dinosaurs of the World that: "It was a fatal mistake [claiming that theropods lacked clavicles], for Henry Osborn had described the collarbones of the theropod Oviraptor just two years before!" So, I reckon, Heilmann just didn't know about the find, and based his thesis on premises that were incorrect even in his own times.
Maybe he did even know about these bones -- AFAIK they were first identified as interclavicles (a bone between the clavicles, lost in apparently all Dinosauromorpha), at a time when nobody knew which bones can be expected in a dinosaur and which can't.
On the other hand, I read from the 'net that "In 1936, Charles Camp discovered the fossil remains of an early Jurassic theropod which possessed clavicles
Segisaurus halli, a coelophysoid "as big as a goose".
after Heilmann's book was published (1996).
 That's Feduccia's book on the same issue :-> . Heilmann's original in Danish (Fuglenes afstamning, IIRC) was published in 1925, the English translation in 1926.
And then, I would like to know if these "clavicles" from Oviraptor and the theropod Camp found (it would also be nice to know what theropod this was) were real furculas or just usual clavicles. I believe clavicles are primitive character of Tetanurans.
Oviraptor? See for yourself at http://www.dinosauria.com/jdp/archie/furcula.html! The clavicles of Segisaurus were mentioned onlist in an interesting thread... some months ago :-] ; IIRC they are broken like those of Carnotaurus, so they may well have been fused into a furcula.
        Clavicles are a synapomorphy of at least Osteichthyes (and they are dermal bones, so they might one day be identified in the sister group of bony fish, the armoured Placodermi).