Archaeocete-like jaws in a baleen whale

  title={Archaeocete-like jaws in a baleen whale},
  author={Erich M. G. Fitzgerald},
  journal={Biology Letters},
  pages={94 - 96}
  • E. Fitzgerald
  • Published 23 February 2012
  • Environmental Science
  • Biology Letters
The titanic baleen whales (Cetacea, Mysticeti) have a bizarre skull morphology, including an elastic mandibular symphysis, which permits dynamic oral cavity expansion during bulk feeding. How this key innovation evolved from the sutured symphysis of archaeocetes has remained unclear. Now, mandibles of the Oligocene toothed mysticete Janjucetus hunderi show that basal mysticetes had an archaeocete-like sutured symphysis. This archaic morphology was paired with a wide rostrum typical of later… 

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