Cool sperm: why some placental mammals have a scrotum

  title={Cool sperm: why some placental mammals have a scrotum},
  author={Barry Gordon Lovegrove},
  journal={Journal of Evolutionary Biology},
  • B. Lovegrove
  • Published 1 May 2014
  • Biology, Environmental Science
  • Journal of Evolutionary Biology
Throughout the Cenozoic, the fitness benefits of the scrotum in placental mammals presumably outweighed the fitness costs through damage, yet a definitive hypothesis for its evolution remains elusive. Here, I present an hypothesis (Endothermic Pulses Hypothesis) which argues that the evolution of the scrotum was driven by Cenozoic pulses in endothermy, that is, increases in normothermic body temperature, which occurred in Boreotheria (rodents, primates, lagomorphs, carnivores, bats… 

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    Biological reviews of the Cambridge Philosophical Society
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