Sperm competition in birds.

  title={Sperm competition in birds.},
  author={Tim R. Birkhead},
  journal={Reviews of reproduction},
  volume={3 2},
  • T. Birkhead
  • Published 1 May 1998
  • Biology, Medicine
  • Reviews of reproduction
Sperm competition in birds occurs when a female is inseminated by more than one male during a single breeding cycle. Despite most birds being socially monogamous, sperm competition is widespread and results in frequent extra-pair paternity. Sperm competition is a fundamental part of sexual selection since it results in differential reproductive success among males. Male adaptations to sperm competition include relatively large testes, large sperm stores and long spermatozoa, mate guarding and… 
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