An alternative hypothesis for the evolution of same-sex sexual behaviour in animals

  title={An alternative hypothesis for the evolution of same-sex sexual behaviour in animals},
  author={Julia D. Monk and Erin Giglio and Ambika Kamath and Max R. Lambert and Caitlin E. McDonough},
  journal={Nature Ecology \& Evolution},
  pages={1622 - 1631}
Same-sex sexual behaviour (SSB) has been recorded in over 1,500 animal species with a widespread distribution across most major clades. Evolutionary biologists have long sought to uncover the adaptive origins of ‘homosexual behaviour’ in an attempt to resolve this apparent Darwinian paradox: how has SSB repeatedly evolved and persisted despite its presumed fitness costs? This question implicitly assumes that ‘heterosexual’ or exclusive different-sex sexual behaviour (DSB) is the baseline… 

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  • M. Ryan
  • Psychology, Biology
    Proceedings of the National Academy of Sciences
  • 2021
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