A caseian point for the evolution of a diaphragm homologue among the earliest synapsids

  title={A caseian point for the evolution of a diaphragm homologue among the earliest synapsids},
  author={Markus Lambertz and Christen D. Shelton and Frederik Spindler and Steve F. Perry},
  journal={Annals of the New York Academy of Sciences},
The origin of the diaphragm remains a poorly understood yet crucial step in the evolution of terrestrial vertebrates, as this unique structure serves as the main respiratory motor for mammals. Here, we analyze the paleobiology and the respiratory apparatus of one of the oldest lineages of mammal‐like reptiles: the Caseidae. Combining quantitative bone histology and functional morphological and physiological modeling approaches, we deduce a scenario in which an auxiliary ventilatory structure… Expand
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