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2023
Abstract Sperm competition is a form of intrasexual competition in which the sperm of two or more males concurrently occupy the reproductive tract of a single female and compete to fertilize an available ovum. As a nonmonogamous species, humans have been subject to selection pressures associated with sperm competition.
Valerie G. Starratt, Todd K. Shackelford
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Abstract Sperm competition is a form of intrasexual competition in which the sperm of two or more males concurrently occupy the reproductive tract of a single female and compete to fertilize an available ovum. As a nonmonogamous species, humans have been subject to selection pressures associated with sperm competition.
Valerie G. Starratt, Todd K. Shackelford
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Mechanisms of sperm competition
Trends in Ecology & Evolution, 1990Sperm competition occurs when two (or more) males inseminate a single female during a reproductive cycle, but what determines which one of them will fertilize her eggs? Is it simply a lottery, or are there some more complex rules by which matings are translated into offspring?
T R, Birkhead, F M, Hunter
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Trends in Ecology & Evolution, 1989
Female promiscuity can lead to the spermatazoa of several males 'competing' to fertilize the ova of a single female. Such promiscuity is relatively common among mammals and has resulted in a suite of adaptations associated with sperm competition. In the last decade, laboratory scientists using experimental techniques have clarified the physiological ...
J R, Ginsberg, U W, Huck
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Female promiscuity can lead to the spermatazoa of several males 'competing' to fertilize the ova of a single female. Such promiscuity is relatively common among mammals and has resulted in a suite of adaptations associated with sperm competition. In the last decade, laboratory scientists using experimental techniques have clarified the physiological ...
J R, Ginsberg, U W, Huck
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Sperm competition games: sperm selection by females
Journal of Theoretical Biology, 2003We analyse a co-evolutionary sexual conflict game, in which males compete for fertilizations (sperm competition) and females operate sperm selection against unfavourable ejaculates (cryptic female choice). For simplicity, each female mates with two males per reproductive event, and the competing ejaculates are of two types, favourable (having high ...
M A, Ball, G A, Parker
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Sperm competition influences sperm size in mammals
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1991Among mammals sperm competition leads to selection for increased sperm numbers but it is not known whether it also leads to changes in sperm size. Two contrasting theoretical predictions have been made. The first hypothesis relies on the assumption that there is a trade-off between sperm numbers and sperm size and predicts that, in species confronting ...
M, Gomendio, E R, Roldan
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Sperm size and sperm competition in birds
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1992In a sample of 20 species of North American passerine birds we found no relation between sperm size and mating system like that previously reported in mammals (Gomendio & Roldan (Proc. R. Soc. Lond. B 243, 181 (1991)). Instead, we found a positive correlation between sperm length and the length of female sperm storage tubules (SSTS) and a negative ...
J V, Briskie, R, Montgomerie
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Human Fertility, 2004
Although Darwin identified the evolutionary significance of competition between males in the context of reproduction, it is only in the past few decades that we have begun to appreciate the importance of competition at the gametic level. Sperm competition, defined as competition between the sperm of two or more males for fertilization of the same set ...
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Although Darwin identified the evolutionary significance of competition between males in the context of reproduction, it is only in the past few decades that we have begun to appreciate the importance of competition at the gametic level. Sperm competition, defined as competition between the sperm of two or more males for fertilization of the same set ...
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Integrative oncology: Addressing the global challenges of cancer prevention and treatment
Ca-A Cancer Journal for Clinicians, 2022Jun J Mao,, Msce +2 more
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