Unlike the dinosaur-like "Archaeornithes", the various types of birds assigned to the Odontognathae had short tails with a plowshare-shaped pygostyle and a well developed carina for flight muscle. They also shared the feature of intramandibular articulation, something that is actually absent in Archaeopteryx, but found in many of its theropod relatives.[2]
The brains of the "odontognath" birds appear to be somewhat simpler than those of modern birds and have retained some "reptilian" traits.[3] Ornithologist Alan Feduccia has used this, and the presence of the intramandibular articulation (a trait also found in mosasaurs and living varanid lizards) as arguments that the Odontognathae and thus the birds as a whole have not evolved from theropod dinosaurs, but non-dinosaur thecodonts.[4] This theory is contested by most paleontologists.[5]
Classification
Classically, Odontognathae was considered one of three superorders of Neornithes (modern birds) as opposed to Archaeornithes (the ancient birds). Today the name Neornithes is commonly used for the bird crown group, the Odontognathae being united with them the group Ornithurae.[6]
^Romer, A. S. & Parsons, T. S. (1985): The Vertebrate Body. (6th ed.) Saunders, Philadelphia.
^Sereno, P., Forster, Rogers and Monetta, (1993): "Primitive dinosaur skeleton from Argentina and the early evolution of Dinosauria." Nature, 361: 64-66.
^Edinger, Tilly (1951). The Brains of the Odontognathae. Society for the Study of Evolution. p. 6
^Feduccia, Alan; Lingham-Soliar, T; Hinchliffe, JR (November 2005). "Do feathered dinosaurs exist? Testing the hypothesis on neontological and paleontological evidence". Journal of Morphology. 266 (2): 125–66. doi:10.1002/jmor.10382. ISSN0362-2525. PMID16217748. S2CID15079072.
^Gauthier, Jacques, de Queiroz, Kevin (2001). "Feathered dinosaurs, flying dinosaurs, crown dinosaurs, and the name 'Aves'". in New Perspective on the Origin and Evolution of Birds: Proceedings of the International Symposium in Honor of John H. Ostrom. Yale Peabody Museum. Yale University. New Haven, Conn. USA