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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Evolution of female promiscuity in Passerides songbirds

BMC Evolutionary Biology, Journal Year: 2019, Volume and Issue: 19(1)

Published: Aug. 14, 2019

Female promiscuity is highly variable among birds, and particularly songbirds. Comparative work has identified several patterns of covariation with social, sexual, ecological life history traits. However, it unclear whether these reflect causes or consequences female promiscuity, if they are byproducts some unknown evolutionary drivers. Moreover, factors that explain at the deep nodes in phylogenetic tree may be different from those important tips, i.e. closely related species. Here we examine relationships between a broad set predictor variables comprehensive data (N = 202 species) Passerides songbirds, which diversified infraorder Passeriformes exhibiting significant variation promiscuity.Female was all major clades phylogeny also We found associations albeit fairly small effect sizes (all R2 ≤ 0.08). More promiscuous species had: 1) less male parental care, during early stages nesting cycle (nest building incubation), 2) more short-term pair bonds, 3) greater degree sexual dichromatism, primarily because females were drabber, 4) migratory behaviour, 5) stronger pre-mating selection. In multivariate model, however, selection disappeared, while other four showed additive effects together explained about 16% total variance promiscuity. no relationship body size, variation, latitude cooperative breeding.We multiple traits associated but generally weak. Some traits, such as reduced care males cryptic plumage females, might even responses to, rather than of, Hence, high remains enigmatic. seems to rapidly evolving trait often diverges similar ecologies breeding systems. A future challenge therefore understand what drives within-lineage over microevolutionary time scales.

Language: Английский

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The mating biology of termites: a comparative review

Animal Behaviour, Journal Year: 2011, Volume and Issue: 82(5), P. 927 - 936

Published: Aug. 29, 2011

Language: Английский

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Haploid selection within a single ejaculate increases offspring fitness

Proceedings of the National Academy of Sciences, Journal Year: 2017, Volume and Issue: 114(30), P. 8053 - 8058

Published: July 11, 2017

Significance Diploid organisms produce haploid gametes for sexual reproduction, resulting in a biphasic life cycle. Although selection during the diploid phase is well understood, gametic stage and its consequences are largely ignored despite potential importance fundamental evolutionary processes, including rate of adaptation inbreeding depression, as applied research into fertilization technology. A current dogma assumes that animals on genotype minimal. We examined zebrafish found strong fitness sperm phenotype offspring. Genomic data support idea these effects may be consequence genotype.

Language: Английский

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Sperm form and function in the absence of sperm competition

Molecular Reproduction and Development, Journal Year: 2013, Volume and Issue: 81(3), P. 204 - 216

Published: Nov. 6, 2013

SUMMARY Sperm competition is a post‐copulatory, sexual selection force that, together with phylogeny and fertilization mode, has been regarded as one of the main factors explaining diversity in sperm size across species. This universal mechanism favors traits that enhance male's fertilizing ability paternity success. Surprisingly, however, characteristics semen quality monogamous species, low risk competition, have barely received any attention. In this review, we consider monogamy two ends selective spectrum, discuss its effect on structure function. We address issue lack by comparing essentially species—their largely degenerative features high degree polymorphisms could be norms for Further, level humans discussed mating strategy, relative testis size, to other primate terms concentration, swimming speed, morphology, seem closer aligned low‐risk situation gorillas than promiscuous chimpanzees. Mol. Reprod. Dev. 2013. © 2013 Wiley Periodicals, Inc .

Language: Английский

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Developmental temperature affects the expression of ejaculatory traits and the outcome of sperm competition in Callosobruchus maculatus

Journal of Evolutionary Biology, Journal Year: 2014, Volume and Issue: 27(9), P. 1811 - 1818

Published: May 30, 2014

Abstract The outcome of post‐copulatory sexual selection is determined by a complex set interactions between the primary reproductive traits two or more males and their with female. Recently, number studies have shown both females express phenotypic plasticity in response to thermal environment experienced during ontogeny. However, how these affects dynamics sperm competition remains largely unknown. Here, we demonstrate testes size, size developmental temperature bruchid beetle Callosobruchus maculatus . Males reared at highest eclosed smallest body had absolute relative size. high‐ low‐temperature extremes produced fewer smaller than intermediate temperatures. In absence competition, no effect on male fertility. under conditions either extreme were less competitive terms offence (P 2 ), whereas those lowest defence 1 ). This suggests pathways that regulate expression ejaculatory are subject natural selection: pre‐ejaculatory post‐ejaculatory environment. nature, heterogeneity development commonplace. Therefore, suggest interplay ecology represents an important, yet hitherto underestimated component fitness via selection.

Language: Английский

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Diet affects ejaculate traits in a lizard with condition-dependent fertilization success

Behavioral Ecology, Journal Year: 2015, Volume and Issue: 26(6), P. 1502 - 1511

Published: Jan. 1, 2015

Sexually selected traits are often driven to costly extremes by persistent directional selection. Energy acquisition and allocation can therefore influence variation in subject both precopulatory postcopulatory sexual selection, though the later have received much less attention. We tested condition dependence of sperm morphology, count, fertilization success a promiscuous lizard (Anolis sagrei) 1) collecting samples from wild males that varied naturally body condition, 2) experimentally altering captive through dietary restriction, 3) analyzing genetic paternity data competitive mating trials between differed condition. In males, length midpiece decreased with Experimental food restriction production, head, increased midpiece, variance morphology within individuals. When restricted single copulation, on high-intake diets exhibited slight but nonsignificant advantage. Reanalysis previous experiment which high- low-condition were sequentially allowed copulate ad libitum for 1 week revealed significant bias favor high-condition males. controlling mean treatment effects proportion offspring sired phenotypes, multiple regression negative correlations head length, count. Collectively, our results suggest condition-dependent A. sagrei may be partially mediated underlying

Language: Английский

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Haploid Selection in “Diploid” Organisms

Annual Review of Ecology Evolution and Systematics, Journal Year: 2019, Volume and Issue: 50(1), P. 219 - 236

Published: July 26, 2019

Evolutionary rates and strength of selection differ markedly between haploid diploid genomes. Any genes expressed in a state will be directly exposed to selection, whereas alleles may partially or fully masked by homologous allele. This difference shape key evolutionary processes, including adaptation inbreeding depression, but also the evolution sex chromosomes, heterochiasmy, stable ratio biases. All organisms carry genomes, most notably genomes gametes produced every sexually reproducing eukaryote. Furthermore, expression occurs with monoallelic expression, organelles, such as mitochondria plastids. A comparison among these reveals striking parallels. Evidence suggests that has potential predominantly organisms, taking advantage rapidly developing technologies, we are now position quantify importance on

Language: Английский

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Experimental evolution reveals that sperm competition intensity selects for longer, more costly sperm

Evolution Letters, Journal Year: 2017, Volume and Issue: 1(2), P. 102 - 113

Published: June 1, 2017

Abstract It is the differences between sperm and eggs that fundamentally underpin sexes within reproduction. For males, it theorized widespread competition leads to selection for investment in numbers, achieved by minimizing size limited resources spermatogenesis testis. Here, we empirically examine how shapes size, after more than 77 generations of experimental replicate lines under either high or low intensities promiscuous flour beetle Tribolium castaneum. After this evolution, populations had diverged significantly their competitiveness, with ejaculates from males evolving gaining 20% greater paternity evolved intensity. Males did not change relative into production following showing no difference testis sizes intensity regimes. However, competitive regimes longer and, across six independently selected lines, there was a significant association degree divergence length average competitiveness. To determine whether such elongation costly, used dietary restriction experiments, revealed protein-restricted produced shorter sperm. Our findings therefore demonstrate can exert positive directional on despite being costly reproductive trait.

Language: Английский

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