Sperm competition. by Wigby, S, Chapman, T

Sperm competition and ejaculate economics. by Parker, G, Pizzari, T

“…Sperm competition mechanisms vary greatly, depending on many factors including the level of sperm competition, space constraints in the sperm competition arena, male mating roles, and female influences on sperm utilisation. …”

Sperm Competition and Fertilization Success by Birkhead, T, Pizzari, T

“…Since male-male competition and female choice can continue after copulation, this area of research is known as post- copulatory sexual selection and comprises both sperm competition and cryptic female choice. Behavioural ecologists concentrated initially on functional (ultimate) issues (the adaptive significance of particular traits) but later also started to address mechanistic (proximate) questions. …”

Genetic Factors Influencing Sperm Competition by Alberto Civetta, José M. Ranz

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SPERM COMPETITION IN THE CHAFFINCH - THE ROLE OF THE FEMALE by Sheldon, B

Experimental evolution of sperm competitiveness in a mammal by Simmons Leigh W, Firman Renée C

“…Studies of experimental evolution have proven the selective action of sperm competition on male reproductive traits. However, while reproductive traits may evolve in response to sperm competition, this does not necessarily provide evidence that sperm competitive ability responds to selection. …”
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Sperm competition and the evolution of sperm design in mammals by Gomendio Montserrat, Tourmente Maximiliano, Roldan Eduardo RS

“…<p>Abstract</p> <p>Background</p> <p>The influence of sperm competition upon sperm size has been a controversial issue during the last 20 years which remains unresolved for mammals. …”
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REPRODUCTIVE ANATOMY OF THE CHAFFINCH IN RELATION TO SPERM COMPETITION by Sheldon, B, Birkhead, T

Semen Displacement as a Sperm Competition Strategy in Humans by Gordon G. Gallup, Rebecca L. Burch

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Sexual selection, germline mutation rate and sperm competition by Møller AP, Cuervo JJ

“…Two hypotheses may account for such elevated mutation: (1) Increased sperm production associated with sperm competition may increase mutation rate. (2) Mutator alleles increase mutation rates that are revealed by the expression of condition-dependent secondary sexual characters used by choosy females during their mate choice. …”
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Human Sperm Competition: A Comparative Evolutionary Analysis by Michael N. Pham, Todd K. Shackelford

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Sperm competition in humans : [electronic book] classic and contemporary readings / by Shackelford, Todd K., Pound, Nicholas, SpringerLink (Online service)

Subjects: “…Sperm competition…”
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Sperm competition selects for sperm quantity and quality in the Australian Maluridae. by Melissah Rowe, Stephen Pruett-Jones

“…Additionally, as sperm competition level increased, the proportion of testicular spermatogenic tissue also increased, suggesting that sperm competition selects for greater sperm production per unit of testicular tissue. …”
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Metabolic rate limits the effect of sperm competition on mammalian spermatogenesis. by Javier delBarco-Trillo, Maximiliano Tourmente, Eduardo R S Roldan

“…Sperm competition leads to increased sperm production in many taxa. …”
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Sperm Competition Risk and Sexual Coercion Predict Copulatory Duration in Humans by Nicole Barbaro, Michael N. Pham, Todd K. Shackelford

“…A man whose romantic partner is sexually unfaithful is at risk of sperm competition and cuckoldry—unwitting investment in offspring to whom he is genetically unrelated. …”
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Increased male investment in sperm competition results in reduced maintenance of gametes. by Mareike Koppik, Julian Baur, David Berger

“…While more work is needed to detail the exact molecular underpinnings of our results, our findings provide rare experimental evidence for a trade-off between male success in sperm competition and germline maintenance. This suggests that sex differences in the relative strengths of sexual and natural selection are causally linked to male mutation bias. …”
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Sperm competition dynamics: ejaculate fertilising efficiency changes differentially with time by Pizzari, T, Worley, K, Burke, T, Froman, D

“…Because females are often sexually promiscuous, this challenge hinges on establishing the mechanisms through which the ejaculates of different males compete for fertilisation (sperm competition). The competitive quality of an ejaculate is mediated by the relative number of live sperm and their motile performance. …”

Experimental analysis of sperm competition mechanisms in a wild bird population. by Michl, G, Török, J, Griffith, S, Sheldon, B

“…Recent work on wild birds has revealed the importance of sperm competition as a source of sexual selection, but behavioral and paternity studies have previously provided only indirect evidence for mechanisms of sperm competition in wild birds. …”

Chemosensory assessment of sperm competition levels and the evolution of internal spermatophore guarding by Carazo, P, Font, E, Alfthan, B

“…Males of many species adjust their reproductive behaviour according to the perceived risk of sperm competition. Although this phenomenon is widespread in insects and other animals, the mechanisms that allow mates to assess sperm competition levels remain largely unexplored. …”

Sperm competition dynamics: ejaculate fertilising efficiency changes differentially with time. by Pizzari, T, Worley, K, Burke, T, Froman, D

“…Because females are often sexually promiscuous, this challenge hinges on establishing the mechanisms through which the ejaculates of different males compete for fertilisation (sperm competition). The competitive quality of an ejaculate is mediated by the relative number of live sperm and their motile performance. …”