Human sperm competition: ejaculate adjustment by males and the function of masturbation

@article{Baker1993HumanSC,
  title={Human sperm competition: ejaculate adjustment by males and the function of masturbation},
  author={R. Robin Baker and Mark A. Bellis},
  journal={Animal Behaviour},
  year={1993},
  volume={46},
  pages={861-885}
}
. Sperm competition theory argues that the number of sperm inseminated into a female by a male is a trade-off between two opposing pressures. On the one hand, the risk that sperm may find themselves in competition with the sperm from another male favours the male inseminating more sperm. On the other hand, ejaculates are costly to produce and males are favoured who economize over the number of sperm inseminated. This paper analyses: (1) sperm numbers and other ejaculation data for 35 human… 
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