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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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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The genetic rescue of two bottlenecked South Island robin populations using translocations of inbred donors

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2012, Volume and Issue: 280(1752), P. 20122228 - 20122228

Published: Dec. 12, 2012

Populations forced through bottlenecks typically lose genetic variation and exhibit inbreeding depression. ‘Genetic rescue’ techniques that introduce individuals from outbred populations can be highly effective in reversing the deleterious effects of inbreeding, but have limited application for majority endangered species, which survive only a few bottlenecked populations. We tested effectiveness using inbred as donors to rescue two isolated South Island robin ( Petroica australis ). Reciprocal translocations significantly increased heterozygosity allelic diversity. Increased diversity was accompanied by juvenile survival recruitment, sperm quality, immunocompetence hybrid (crosses between populations) compared with control within each population). Our results confirm implementation ‘genetic provides way preserving species restoring their viability when donor no longer exist.

Language: Английский

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Good sperm producers are more likely to participate in incubation in the Asian barn swallow Hirundo rustica gutturalis

Behavioural Processes, Journal Year: 2025, Volume and Issue: 226, P. 105173 - 105173

Published: March 1, 2025

Language: Английский

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Evolutionary origins and persistence of infidelity in Malurus : the least faithful birds

Emu - Austral Ornithology, Journal Year: 2013, Volume and Issue: 113(3), P. 208 - 217

Published: Aug. 15, 2013

Fairy-wrens (genus Malurus maintain territories year round, and breed cooperatively, with all members of the social group provisioning young. Despite living several adult males, breeding female typically cuckolds them, seeking fertilisations from extra-group males that provide no care to her offspring, instead caring for young reared on their own territory. We trace evolutionary origins persistence this extraordinary combination traits. argue high rate infidelity in some fairy-wrens facilitates pairing among nuclear family relatives, rather than being an response avoid inbreeding. It seems likely females mate improve genetic quality offspring. The ability plumage long periods is primary criterion choice; only older can do so. Several features mating system undermine accuracy choice, low-quality exploit uncertainty. Extra-group matings by help stabilise but may leave it vulnerable collapse under certain circumstances. Nonetheless, sexual selection most species very strong, confirming utility as model organisms study choice intersexual selection.

Language: Английский

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Postcopulatory Sexual Selection Results in Spermatozoa with More Uniform Head and Flagellum Sizes in Rodents

PLoS ONE, Journal Year: 2014, Volume and Issue: 9(9), P. e108148 - e108148

Published: Sept. 22, 2014

Interspecific comparative studies have shown that, in most taxa, postcopulatory sexual selection (PCSS) the form of sperm competition drives evolution longer and faster swimming sperm. Work on passserine birds has revealed that PCSS also reduces variation size between males at intraspecific level. However, influence upon intra-male diversity is poorly understood, since few carried out to date yielded contradictory results. In mammals, increases but there little information effects this selective force variations shape. Here, we test whether associates with a reduction degree dimensions rodents. We found as levels increase produce are more similar both head flagellum. On other hand, whereas increasing less length relation width (ratio CV length/CV width), no flagellum sizes length). Thus, it appears addition for sperm, may select uniform heads flagella, which together enhance velocity. Overall, seems drive components towards an optimum design affect performance which, turn, will be crucial successful fertilization.

Language: Английский

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Seasonal variation in ejaculate traits of male red-winged blackbirds (Agelaius phoeniceus)

Behavioral Ecology and Sociobiology, Journal Year: 2012, Volume and Issue: 66(12), P. 1607 - 1617

Published: Sept. 22, 2012

Language: Английский

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THE MAINTENANCE OF SPERM VARIABILITY: CONTEXT-DEPENDENT SELECTION ON SPERM MORPHOLOGY IN A BROADCAST SPAWNING INVERTEBRATE

Evolution, Journal Year: 2012, Volume and Issue: unknown, P. no - no

Published: Dec. 1, 2012

Why are sperm so variable despite having a singular, critical function and an intimate relationship with fitness? A key to understanding the evolution of morphology is identifying which traits enable be successful fertilizers. Several (e.g., tail length, overall size) implicated in performance, but benefits these likely highly context dependent. Here, we examined phenotypic selection on broadcast spawning tube worm (Galeolaria gemineoa). We conducted laboratory experiments measure between average relative fertilization success across range environments that were designed approximate concentrations ages encountered by eggs nature. found strength form multivariate varied substantially our environmental gradients. Sperm long tails small heads favored high-concentration environments, whereas at low old ages. suggest variation local environment resulting differences can preserve variability both within among males.

Language: Английский

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Morphology‐function relationships and repeatability in the sperm of Passer sparrows

Journal of Morphology, Journal Year: 2014, Volume and Issue: 276(4), P. 370 - 377

Published: Nov. 26, 2014

ABSTRACT Sperm performance is likely to be an important determinant of male reproductive success, especially when females copulate with multiple males. Understanding sperm therefore crucial fully understand the evolution strategies. In this study, we examined repeatability morphology and motility measures over three breeding seasons, studied relationships between function. We conducted study in wild‐derived captive house sparrows ( Passer domesticus ) Spanish P. hispaniolensis ). Results for two species were similar. As predicted from results other passerine species, total length was highly repeatable across ejaculates, components moderate. The swimming speed ejaculates lower, but statistically significant, suggesting that velocity may a relatively dynamic trait. Surprisingly, did not correlate relative midpiece, it correlated negatively flagellum length. This pattern opposite what theory predicts differs has been found before. Also contrary previous work, no evidence correlates longevity. These highlight need better understanding function birds. J. Morphol. 276:370–377, 2015. © 2014 Wiley Periodicals, Inc.

Language: Английский

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Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards

Ecology and Evolution, Journal Year: 2014, Volume and Issue: 4(21), P. 4080 - 4092

Published: Oct. 7, 2014

Abstract In polyandrous species, sperm morphometry and velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of competition in trait variation, this aspect is still poorly understood. It has suggested that an increase pressure could reduce size variation or produce a diversity maximize male fertilization success. We aim at elucidating variability morphometric traits two Tupinambis lizards context risk. Sperm showed substantial all levels examined: between among males within ejaculate individual males. was found be positively correlated with flagellum: midpiece ratio, relatively longer flagella associated faster sperm. Our results document high form function lizards.

Language: Английский

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