Human sperm competition: testis size, sperm production and rates of extrapair copulations

@article{Simmons2004HumanSC,
  title={Human sperm competition: testis size, sperm production and rates of extrapair copulations},
  author={Leigh W. Simmons and Ren{\'e}e C. Firman and Gillian Rhodes and Marianne Peters},
  journal={Animal Behaviour},
  year={2004},
  volume={68},
  pages={297-302}
}
We examined the claim that sperm competition is an important selection pressure operating in human populations. [...] Key Method We recruited 222 men and 194 women to complete a survey of their sexual behaviour. Of these, 28% of men and 22% of women reported engaging in extrapair copulations (EPCs). A review of the literature suggests that rates of extrapair paternity are in the region of 2%. These values suggest that the risk of sperm competition in humans is relatively low, in line with comparative studies of…Expand

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