Sexual dimorphism in sea lion pups: differential maternal investment, or sex-specific differences in energy allocation?

  title={Sexual dimorphism in sea lion pups: differential maternal investment, or sex-specific differences in energy allocation?},
  author={Kathryn A. Ono and Daryl J. Boness},
  journal={Behavioral Ecology and Sociobiology},
  • K. Ono, D. Boness
  • Published 25 January 1996
  • Psychology, Biology
  • Behavioral Ecology and Sociobiology
Abstract Proximal mechanisms underlying a faster growth rate in male compared to female California sea lion pups were investigated. Males are significantly larger at birth than females. Specifically, we asked if differential maternal investment contributed to enhanced male growth via: (1) larger mothers having disproportionately more male pups, (2) more time and energy put into foraging by mothers of male pups, and (3) greater milk production in mothers of male pups. We also considered four… 

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