Sperm wars and the evolution of male fertility

Reproduction, Journal Year: 2012, Volume and Issue: 144(5), P. 519 - 534

Published: Sept. 15, 2012

Females frequently mate with several males, whose sperm then compete to fertilize available ova. Sperm competition represents a potent selective force that is expected shape male expenditure on the ejaculate. Here, we review empirical data illustrate evolutionary consequences of competition. favors evolution increased testes size and production. In some species, males appear capable adjusting number ejaculated, depending perceived levels Selection also act form function, although evidence for this remains equivocal. Comparative studies suggest length swimming speed may increase in response selection from However, mechanisms driving pattern remain unclear. Evidence influences mixed fertilization trials performed across broad range species demonstrate inconsistent relationships between function. This ambiguity part reflect important role seminal fluid proteins (sfps) play affecting There good sfps are subject competition, recent work pointing an ability adjust their chemistry rival males. We argue future research must consider components ejaculate as functional unity. Research at genomic level will identify genes ultimately control fertility.

Language: Английский

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Sperm competition and the evolution of sperm design in mammals

BMC Evolutionary Biology, Journal Year: 2011, Volume and Issue: 11(1)

Published: Jan. 13, 2011

Abstract Background The influence of sperm competition upon size has been a controversial issue during the last 20 years which remains unresolved for mammals. hypothesis that, when ejaculates compete with rival males, an increase in would make more competitive because it swimming speed, generated contradictory results from both theoretical and empirical studies. In addition, debate extended to components should size: midpiece accommodate mitochondria produce energy fuel motility, or principal piece generate greater propulsion forces. Results this study we examined design mammals using much larger data set (226 species) than previous analyses, corrected phylogenetic effects by complete resolved phylogeny, robust control methods. Our show as increases, all integrated manner heads become elongated. length was found be associated enhanced velocity, adaptive trait under competition. Conclusions We conclude that played important role evolution mammals, discuss why studies have failed detect it.

Language: Английский

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Sexual selection and the evolution of sperm quality

Molecular Human Reproduction, Journal Year: 2014, Volume and Issue: 20(12), P. 1180 - 1189

Published: Oct. 16, 2014

Sperm experience intense and varied selection that dramatically impacts the evolution of sperm quality. Selection acts to ensure are fertilization-competent able overcome many challenges experienced on their way towards eggs. However, simply being fertilize an egg is not enough male fertility in most species. Owing prevalence female multiple mating throughout animal kingdom, successful fertilization requires outcompete rival sperm. In addition, females can actively influence quality, storage or utilization fertility. This review provides overview how these selective forces After exploring link between traits fertility, we examine post-mating competition ejaculates influences We then describe complex genetic, social sexual interactions focusing importance seminal fluid female's reproductive tract. light complexities traits, greater use multivariate approaches incorporate male–male, sperm–sperm sperm–female study quality will enhance our understanding factors influencing Because metric success—fertilization—is same across argue information about gained from non-human animals has enormous potential further impact human

Language: Английский

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COMPARATIVE EVIDENCE FOR THE EVOLUTION OF SPERM SWIMMING SPEED BY SPERM COMPETITION AND FEMALE SPERM STORAGE DURATION IN PASSERINE BIRDS

Evolution, Journal Year: 2009, Volume and Issue: 63(9), P. 2466 - 2473

Published: April 30, 2009

Sperm swimming speed is an important determinant of male fertility and sperm competitiveness. Despite its fundamental biological importance, the underlying evolutionary processes affecting this reproductive trait are poorly understood. Using a comparative approach in phylogenetic framework, we tested predictions that swim faster with (1) increased risk competition, (2) shorter duration female storage, (3) length. We recorded 42 North American European free-living passerine bird species, representing 35 genera 16 families. found was positively related to frequency extrapair paternity (a proxy for competition) negatively associated clutch size storage). unrelated length, although length also paternity. These results suggest not closely traits evolve independently response competition birds. Our findings emphasize significance both storage as forces driving speed.

Language: Английский

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How Multivariate Ejaculate Traits Determine Competitive Fertilization Success in Drosophila melanogaster

Current Biology, Journal Year: 2012, Volume and Issue: 22(18), P. 1667 - 1672

Published: July 26, 2012

Language: Английский

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How sperm competition shapes the evolution of testes and sperm: a meta-analysis

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2020, Volume and Issue: 375(1813), P. 20200064 - 20200064

Published: Oct. 18, 2020

Females of many species mate with multiple males, thereby inciting competition among ejaculates from rival males for fertilization. In response to increasing sperm competition, are predicted enhance their investment in production. This prediction is so widespread that testes size (correcting body size) commonly used as a proxy even the absence any other information about species' reproductive behaviour. By contrast, debate whether selects smaller or larger has persisted nearly three decades, empirical studies demonstrating every possible response. Here, we synthesize 40 years research meta-analytical framework determine how evolution number (i.e. and head, midpiece, flagellum total length) influenced by varying levels across species. Our findings support long-held assumption higher associated relatively testes. We also find clear evidence increases all components length. discuss these results context different theoretical predictions general patterns breeding biology selective environment sperm. article part theme issue ‘Fifty competition’.

Language: Английский

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Comparative analysis of mammalian sperm ultrastructure reveals relationships between sperm morphology, mitochondrial functions and motility

Reproductive Biology and Endocrinology, Journal Year: 2019, Volume and Issue: 17(1)

Published: Aug. 15, 2019

Sperm morphology mainly refers to the shape of head, length flagellar segments, including midpiece, principal piece and end piece, size accessory structures, axonemes, outer dense fibers (ODFs), mitochondrial sheath (MS) fibrous (FS). Across species, there is considerable diversity in morphology. An established theory posits that sperm flagellum, especially a critical factor influencing metabolism velocity. However, our understanding relationships between ultrastructures incomplete. The morphologies from 10 mammalian human, mouse, rat, dog, rabbit, goat, pig, bull, guinea pig golden hamster, were examined by scanning electron microscopy (SEM) transmission (TEM). According SEM TME images, heads cross-sectional areas structures flagella width measured using Image J software. variation tendencies (referred as slope) along calculated linear regression method. Mitochondrial functions commercial kits. velocities CASA three-dimensional species slopes internal obtained. axoneme tapered slightly base tip axonemes correlated negatively with variability across species. Additionally, ODFs and/or MS positively lengths total well velocities. volumes ATP content swimming Our results not only show relationship physiology but also provide sizes mitochondria new targets which study regulation

Language: Английский

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Sperm form and function: what do we know about the role of sexual selection?

Reproduction, Journal Year: 2018, Volume and Issue: 155(5), P. R229 - R243

Published: Feb. 20, 2018

Sperm morphological variation has attracted considerable interest and generated a wealth of predominantly descriptive studies over the past three centuries. Yet, apart from biophysical linking sperm morphology to swimming velocity, surprisingly little is known about adaptive significance form selective processes underlying its tremendous diversification throughout animal kingdom. Here, we first discuss challenges examining in an evolutionary context why our understanding it far complete. Then, review empirical evidence for how sexual selection theory applies evolution function, including putative secondary traits borne by sperm.

Language: Английский

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Computer assisted sperm morphometry in mammals: A review

Animal Reproduction Science, Journal Year: 2015, Volume and Issue: 156, P. 1 - 12

Published: March 10, 2015

Language: Английский

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Long sperm fertilize more eggs in a bird

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2014, Volume and Issue: 282(1799), P. 20141897 - 20141897

Published: Dec. 15, 2014

Sperm competition, in which the ejaculates of multiple males compete to fertilize a female's ova, results strong selection on sperm traits. Although size and swimming velocity are known independently affect fertilization success certain species, exploring relationship between length, still remains challenge. Here, we use zebra finch ( Taeniopygia guttata ), where influences velocity, determine effect total length success. competition experiments, pairs whose differed only speed, revealed that producing long were more successful terms (i) number reaching ova (ii) fertilizing those ova. Our reveal although is main factor determining outcome complex interactions male female reproductive traits may also be important. The mechanisms underlying these poorly understood, but suggest differences storage utilization by females contribute competition.

Language: Английский

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