The teeth of the “toothless”: novelties and key innovations in the evolution of xenarthrans (Mammalia, Xenarthra)

  title={The teeth of the “toothless”: novelties and key innovations in the evolution of xenarthrans (Mammalia, Xenarthra)},
  author={Sergio Fabi{\'a}n Vizcaino},
  • S. Vizcaino
  • Published in Paleobiology 8 July 2009
  • Environmental Science, Geography
Abstract A combination of historical, functional, and biomechanical constraints has shaped the masticatory apparatus of fossil and extant xenarthrans. Among the more notable features are the teeth: hypselodont; commonly reduced in size, complexity, and number; separated by short diastema; and composed of osteodentine. Enamel is absent, as are the cuspal patterns of other mammals. A comprehensive revision of teeth and other features of the masticatory apparatus of xenarthrans reveals that… 

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