Breathing in a box: Constraints on lung ventilation in giant pterosaurs

  title={Breathing in a box: Constraints on lung ventilation in giant pterosaurs},
  author={Nicholas R. Geist and Willem J. Hillenius and Eberhard Frey and Terry D. Jones and Ross A. Elgin},
  journal={The Anatomical Record},
Pterosaurs were the first vertebrates to achieve active flight, with some derived forms reaching enormous size. Accumulating fossil evidence confirms earlier indications that selection for large size in these flying forms resulted in a light, yet strong skeleton characterized by fusion of many bones of the trunk. However, this process also added mechanical constraints on the mobility of the thorax of large pterosaurs that likely limited the options available for lung ventilation. We present an… 
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