Dinosaur Monophyly and a New Class of Vertebrates

@article{Bakker1974DinosaurMA,
  title={Dinosaur Monophyly and a New Class of Vertebrates},
  author={Robert T. Bakker and Peter M. Galton},
  journal={Nature},
  year={1974},
  volume={248},
  pages={168-172}
}
TRADITIONALLY dinosaurs are classified as two or three separate, independent groups of reptiles in the Subclass Archosauria. But evidence from bone histology, locomotor dynamics, and predator/prey ratios strongly suggest that dinosaurs were endotherms with high aerobic exercise metabolism, physiologically much more like birds and cursorial mammals than any living reptiles1–8. Recently Ostrom has argued forcefully that birds are direct descendants of dinosaurs and inherited high exercise… 

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...

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