New light on the Origin of Birds and Crocodiles

@article{Walker1972NewLO,
  title={New light on the Origin of Birds and Crocodiles},
  author={A. D. Walker},
  journal={Nature},
  year={1972},
  volume={237},
  pages={257-263}
}
Detailed evidence from the skull of Sphenosuchus, and from embryological and other resemblances between birds and crocodiles, suggests that these two groups are much more closely related than has been realized 
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TLDR
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TLDR
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TLDR
It is suggested that the early stage in avian flight was an arboreal tetrapod and no intermediate bipedal stage was required and Archaeopteryx was probably an accomplished glider with some powered flight potential. Expand
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A NEW SPECIMEN OF AN EARLY CROCODYLOMORPH (CF. SPHENOSUCHUS SP.) FROM THE UPPER TRIASSIC CHINLE FORMATION OF PETRIFIED FOREST NATIONAL PARK, ARIZONA
TLDR
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The Ancestry of Birds
WALKER1 has restated the long-held belief that both birds and crocodiles evolved from thecodont ancestors, but he added the novel suggestion that these two groups arose from a common thecodontExpand
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