Sperm competition is defined as a form of sexual selection that occurs when ejaculates from multiple males compete for the fertilization of an individual female’s ova. Most female organisms are known to mate with multiple males, so sperm competition is considered to be a widespread and powerful evolutionary force. Competition between males may occur before or after copulation, to either prevent or win competitions, leading to the evolution of numerous traits to enhance fertilization success. Sperm competition sensu stricto refers only to the competition between ejaculates after two males have inseminated the same female.
The theoretical basis of sperm competition was formalized by Parker (1970) and relied on several key observations. The first is that the evolution of internal, or close to internal, fertilization was not only subject to natural selection pressures to maximize fertilization chances for each ovum, but also sexual selection between competing males...
- Arnqvist, G., & Rowe, L. (2013). Sexual conflict. Princeton: Princeton University Press.Google Scholar
- Birkhead, T. R., & Møller, A. P. (1998). Sperm competition and sexual selection. London: Elsevier.Google Scholar
- Birkhead, T. R., Hosken, D. J., & Pitnick, S. S. (2009). Sperm biology: An evolutionary perspective. Cambridge, MA: Academic.Google Scholar
- Durrant, K. L., Skicko, I. M., Sturrock, C., & Mowles, S. L. (2016). Comparative morphological trade-offs between pre- and post-copulatory sexual selection in Giant hissing cockroaches (Tribe: Gromphadorhini). Scientific Reports, 6, 36755. https://doi.org/10.1038/srep36755.CrossRefPubMedPubMedCentralGoogle Scholar
- Eberhard, W. G. (1996). Female control: Sexual selection by cryptic female choice. Princeton: Princeton University Press.Google Scholar
- Gack, C., & Peschke, K. (2005). “Shouldering” exaggerated genitalia: A unique behavioural adaptation for the retraction of the elongate intromittant organ by the male rove beetle (Aleochara tristis Gravenhorst). Biological Journal of the Linnean Society, 84(2), 307–312. https://doi.org/10.1111/j.1095-8312.2005.00432.x.CrossRefGoogle Scholar
- Immler, S., Pitnick, S., Parker, G. A., Durrant, K. L., Lüpold, S., Calhim, S., & Birkhead, T. R. (2011). Resolving variation in the reproductive trade-off between sperm size and number. Proceedings of the National Academy of Sciences, 108(13), 5325–5330. https://doi.org/10.1073/pnas.1009059108.CrossRefGoogle Scholar
- Leonard, J., & Cordoba-Aguilar, A. (Eds.). (2010). The evolution of primary sexual characters in animals. Oxford/New York: Oxford University Press.Google Scholar
- Parker, G. A. (1970). Sperm competition and its evolutionary consequences in the insects. Biological Reviews, 45(4), 525–567. https://doi.org/10.1111/j.1469-185X.1970.tb01176.x.CrossRefGoogle Scholar
- Rudolfsen, G., Figenschou, L., Folstad, I., Tveiten, H., & Figenschou, M. (2006). Rapid adjustments of sperm characteristics in relation to social status. Proceedings of the Royal Society of London B: Biological Sciences, 273(1584), 325–332. https://doi.org/10.1098/rspb.2005.3305.CrossRefGoogle Scholar
- Shuster, S. M., & Wade, M. J. (2003). Mating systems and strategies. Princeton: Princeton University Press.Google Scholar
- Simmons, L. W. (2001). Sperm competition and its evolutionary consequences in the insects. Princeton: Princeton University Press.Google Scholar
- Wedell, N. (1993). Spermatophore size in bushcrickets: Comparative evidence for nuptial gifts as a sperm protection device. Evolution, 47(4), 1203–1212. https://doi.org/10.1111/j.1558-5646.1993.tb02147.x.CrossRefPubMedGoogle Scholar