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Cells, 2021 Mammals exhibit a tremendous amount of variation in sperm morphology and despite the acknowledgement of sperm structural diversity across taxa, its functional significance remains poorly understood. Of particular interest is the sperm of rodents.
Kristin A. Hook +2 more
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Sperm competition in bats [PDF]
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1997 (Uploaded by Plazi for the Bat Literature Project) Sperm competition is a widespread phenomenon influencing the evolution of male anatomy, physiology and behaviour. Bats are an ideal group for studying sperm competition. Females store fertile sperm for up to 200 days and the size of social groups varies from single animals to groups of hundreds of ...
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Metabolic rate limits the effect of sperm competition on mammalian spermatogenesis.
PLoS ONE, 2013 Sperm competition leads to increased sperm production in many taxa. This response may result from increases in testes size, changes in testicular architecture or changes in the kinetics of spermatogenesis, but the impact of each one of these processes on
Javier delBarco-Trillo +2 more
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Sperm competition in birds [PDF]
Reviews of Reproduction, 1987 Sperm competition in birds occurs when a female is inseminated by more than one male during a single breeding cycle. Despite most birds being socially monogamous, sperm competition is widespread and results in frequent extra-pair paternity. Sperm competition is a fundamental part of sexual selection since it results in differential reproductive success
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Testes mass, but not sperm length, increases with higher levels of polyandry in an ancient sex model. [PDF]
PLoS ONE, 2014 There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition.
David E Vrech +3 more
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Do Men Produce Higher Quality Ejaculates When Primed With Thoughts of Partner Infidelity?
Evolutionary Psychology, 2018 Sperm competition theory can be used to generate the hypothesis that men alter the quality of their ejaculates as a function of sperm competition risk.
Michael N. Pham +10 more
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Pitfalls in experiments testing predictions from sperm competition theory [PDF]
, 2005 Engqvist L, Reinhold K. Pitfalls in experiments testing predictions from sperm competition theory. Journal of Evolutionary Biology. 2005;18(1):116-123.As females of many species mate with more than one male, ejaculates often face competition from the ...
Reinhold, Klaus +3 more
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Why small males have big sperm: dimorphic squid sperm linked to alternative mating behaviours
BMC Evolutionary Biology, 2011 Background Sperm cells are the target of strong sexual selection that may drive changes in sperm structure and function to maximize fertilisation success. Sperm evolution is regarded to be one of the major consequences of sperm competition in polyandrous
Shiba Kogiku +5 more
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Genetic variance and genotype reaction norms in response to larval food manipulation for a trait important in scorpionfly sperm competition. [PDF]
, 2008 Engqvist L. Genetic variance and genotype reaction norms in response to larval food manipulation for a trait important in scorpionfly sperm competition. Functional Ecology. 2008;22(1):070915213639001-???Sperm competition is an important attribute of many
L. Engqvist +1 more
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Media Peternakan, 2013 The objective of this study was to examine the relationship between sperm morphometry and sperm competition in local goats. Forty bucks were used in this study, consisted of 4 breeds namely Ettawa Grade Goat (EGG), Kejobong Goat (KJG), Kacang Goat (KCG),
S. B. Wibowo +2 more
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