Evidence for Endothermic Ancestors of Crocodiles at the Stem of Archosaur Evolution

@article{Seymour2004EvidenceFE,
  title={Evidence for Endothermic Ancestors of Crocodiles at the Stem of Archosaur Evolution},
  author={R. Seymour and C. Bennett-Stamper and S. D. Johnston and D. Carrier and G. Grigg},
  journal={Physiological and Biochemical Zoology},
  year={2004},
  volume={77},
  pages={1051 - 1067}
}
Physiological, anatomical, and developmental features of the crocodilian heart support the paleontological evidence that the ancestors of living crocodilians were active and endothermic, but the lineage reverted to ectothermy when it invaded the aquatic, ambush predator niche. In endotherms, there is a functional nexus between high metabolic rates, high blood flow rates, and complete separation of high systemic blood pressure from low pulmonary blood pressure in a four‐chambered heart… Expand
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