Aquatic Adaptation and Swimming Mode Inferred from Skeletal Proportions in the Miocene Desmostylian Desmostylus

  title={Aquatic Adaptation and Swimming Mode Inferred from Skeletal Proportions in the Miocene Desmostylian Desmostylus},
  author={Philip D. Gingerich},
  journal={Journal of Mammalian Evolution},
  • P. Gingerich
  • Published 1 June 2005
  • Biology
  • Journal of Mammalian Evolution
Desmostylians are enigmatic, extinct, semiaquatic marine mammals that inhabited coastlines of the northern Pacific Rim during the late Oligocene through middle Miocene. Principal components analysis (PCA) of trunk and limb proportions provides a rational multivariate context for separating living semiaquatic mammals on three orthogonal axes: a size axis (PC-I), a degree of aquatic adaptation axis (PC-II), and a forelimb- versus hind-limb-dominated locomotion axis (PC-III). The necessary… 

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