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Tarsitano's challenges



      I am still trying to play "catch up" on the theropod-bird controversy. I am wondering which of the following problems posed by Tarsitano in 1991 (Archaeopteryx: Quo Vadis) are still problematic, and which have been resolved by newer coelurosaur fossils:
      "The following morphological problems involving the theropod ancestry of birds must be addressed by those who favor a coelurosaurian ancestry or sister-group position for birds:
      (1) the absence of a siphonium and pneumatic quadrate in all coelurosaurs;
      (2) the lack of clear evidence of a fenestra rotundum in coelurosaurs;
      (3) nonavian tooth morphology in coelurosaurs;
      (4) reduced coracoids in all coelurosaurs;
      (5) the presence of a massive and specialized pelvis and hindlimbs that, biomechanically, seem to argue against the devlopment of flight;
      (6) the presence of the middle temporal arch in coelurosaurs, but its absence in birds;
      (7) the presence of lateral basicranial sinus openings in coelurosaurs, but their absence in birds.
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