Energetic tradeoffs control the size distribution of aquatic mammals

  title={Energetic tradeoffs control the size distribution of aquatic mammals},
  author={William Gearty and Craig R. McClain and Jonathan L. Payne},
  journal={Proceedings of the National Academy of Sciences},
  pages={4194 - 4199}
Significance The reasons why aquatic mammals exhibit larger average sizes than their terrestrial relatives have long been debated. Most previous hypotheses have focused on releases from terrestrial constraints on large sizes. Through the analysis of mammal size distributions, we find the aquatic realm imposes stronger constraints on body size than does the terrestrial realm, driving and confining aquatic mammals to larger sizes. Calculations of energy intake and demand as a function of body… 

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