Sperm divergence in a passerine contact zone: Indication of reinforcement at the gametic level

Evolution, Journal Year: 2018, Volume and Issue: 73(2), P. 202 - 213

Published: Dec. 31, 2018

Postcopulatory sexual selection may promote evolutionary diversification in sperm form, but the contribution of between‐species divergence morphology to origin reproductive isolation and speciation remains little understood. To assess possible role isolation, we studied two closely related bird species, common nightingale (Luscinia megarhynchos) thrush luscinia), that hybridize a secondary contact zone spanning Central Eastern Europe. We found: (1) striking between species total length, accompanied by difference length mitochondrial component; (2) greater sympatry than allopatry, with evidence for character displacement head detected L. megarhynchos; (3) interspecific hybrids showing intermediate parental no decreased quality (the proportion abnormal spermatozoa ejaculates). Our results demonstrate does not result intrinsic postzygotic contribute postcopulatory prezygotic isolation. This could be strengthened reinforcement.

Language: Английский

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Sperm morphology, sperm motility and paternity success in the bluethroat (Luscinia svecica)

PLoS ONE, Journal Year: 2018, Volume and Issue: 13(3), P. e0192644 - e0192644

Published: March 6, 2018

Postcopulatory sexual selection may select for male primary characteristics like sperm morphology and motility, through competition or cryptic female choice. However, how such influence fertilization success remains poorly understood. In this study, we investigate possible correlations between paternity in the socially monogamous bluethroat (Luscinia svecica svecica), predicting that length swimming speed is positively correlated with success. total, 25% (15/61) of broods contained extra-pair offspring 10% (33/315) were sired by males. Paternity did not correlate significantly any aspects motility. Furthermore, motility morphological characters previously have been shown to be associated Thus, investigated here do appear strong predictors bluethroats.

Language: Английский

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Species-level divergences in multiple functional traits between the two endemic subspecies of Blue Chaffinches Fringilla teydea in Canary Islands

BMC Zoology, Journal Year: 2016, Volume and Issue: 1(1)

Published: Aug. 18, 2016

One of the biggest challenges in avian taxonomy is delimitation allopatric species because their reproductive incompatibility cannot be directly studied wild. Instead, has to inferred from multiple, divergent character sets that indicate a low likelihood populations amalgamating upon secondary contact. A set quantitative criteria for been developed taxonomy. Here, we report broad multi-trait comparison two insular subspecies Blue Chaffinch Fringilla teydea, endemic pine forests Tenerife (ssp. teydea) and Gran Canaria polatzeki) Canary Islands. We found taxa were reciprocally monophyletic whole mitogenomes Z chromosome introns. The genetic distance indicates around 1 Mya evolution. There diagnostic differences body morphometrics, song plumage reflectance spectra, whose combined divergence score (=11) exceeds threshold level (=7) by Tobias et al. (Ibis 152:724–746, 2010). Moreover, marked sperm lengths with little range overlap. Relatively long intra- intermale CV compared other passerines suggest mating system high levels competition (extrapair paternity) these taxa. large divergences multiple functional traits qualify rank, i.e., (Fringilla polatzeki). encourage wider use might signal at postcopulatory prezygotic stage, especially competition.

Language: Английский

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Extensive variation in sperm morphology in a frog with no sperm competition

BMC Evolutionary Biology, Journal Year: 2016, Volume and Issue: 16(1)

Published: Feb. 1, 2016

Recent comparative studies of several taxa have found that within-species variation in sperm size decreases with increasing levels competition, suggesting male-male gamete competition selects for an optimal phenotype. Previous intraspecific length all involved internal fertilizers where some other factors-e.g., storage and movement along the walls female's reproductive tract-probably also influence reduce variation. Thus external fertilizers, those factors are absent, might be expected to exhibit even more when there is little or no competition. To test idea, we studied morphology a North American chorus frog, spring peeper (Pseudacris crucifer), species which males encounter competition.As expected, was highly variable peeper, largely due flagellum within among individual males, populations between mitochondrial lineages southwestern Ontario. In addition, large proportion spermatozoa abnormal such way ability fertilize probably compromised. There were differences frequencies abnormalities lineages.In absence suggest genetic drift has played role generation diversity this species, potentially resulting observed populations. Such interpopulation difference increase degree isolation before isolating mechanisms evolve.

Language: Английский

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Longer Sperm Swim More Slowly in the Canary Islands Chiffchaff

Cells, Journal Year: 2021, Volume and Issue: 10(6), P. 1358 - 1358

Published: May 31, 2021

Sperm swimming performance affects male fertilization success, particularly in species with high sperm competition. Understanding how morphology impacts is therefore important. speed hypothesized to increase total length, relative flagellum length (with the generating forward thrust), and midpiece (as contains mitochondria). We tested these hypotheses for divergence traits five island populations of Canary Islands chiffchaff (Phylloscopus canariensis). confirmed incipient mitochondrial DNA differentiation between Gran Canaria other islands. correlated negatively did not correlate (for only). The proportion motile cells increased on only. was similar across thus add a growing number studies passerine birds that do support morphology–swimming hypotheses. suggest mechanics are sufficiently different from mammalian predictions hydrodynamic models should no longer be applied this taxon. While both likely under selection passerines, relationship them requires further elucidation.

Language: Английский

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Consistent Differences in Sperm Morphology and Testis Size between Native and Introduced Populations of Three Anolis Lizard Species

Journal of Herpetology, Journal Year: 2017, Volume and Issue: 51(4), P. 532 - 537

Published: Sept. 20, 2017

Sperm morphology can be highly variable among individuals and across species, but less is known about its variation populations. Within the past 20–80 yr, several species of Anolis lizards have been introduced to Miami, Florida, USA from different source islands in Caribbean, thereby permitting comparisons sperm between native populations multiple species. We collected samples sagrei (Bahamas), distichus (Dominican Republic), cristatellus (Puerto Rico) compared them each that are now sympatric Miami. In these three had with shorter tails larger midpieces relative also measured testis size A. found smaller testes for a given body their counterparts. The consistency differences argues against random genetic drift as an explanation, suggesting instead may exhibit predictable phenotypic plasticity or adaptation response process introduction and/or shared local environment Florida. Though population male reproductive physiology repeatable, underlying causes require further study.

Language: Английский

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Sperm as a speciation phenotype in promiscuous songbirds

Evolution, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

Abstract Sperm morphology varies considerably among species. traits may contribute to speciation if they diverge fast in allopatry and cause conspecific sperm precedence upon secondary contact. However, their role driving prezygotic isolation has been poorly investigated. Here we test the hypothesis that, early process, female promiscuity promotes a reduction overlap length distributions songbird populations. We assembled data set of 20 pairs populations with known distributions, published estimate divergence time, an index derived from extrapair paternity rates or relative testis size. found that diverged more rapidly promiscuous Faster between was caused by lower variance trait species, not faster mean lengths. The reduced is presumably due stronger stabilizing selection on mediated competition. If divergent optima causes sympatry, which remains be shown empirically, promote isolation, rapid songbirds.

Language: Английский

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Current landscape attributes and landscape stability in breeding grounds explain genetic differentiation in a long‐distance migratory bird

Animal Conservation, Journal Year: 2020, Volume and Issue: 24(1), P. 120 - 134

Published: Aug. 2, 2020

Abstract Numerous studies have highlighted a major role of isolation by both geographic distance and current landscape resistance in controlling bird population genetic differentiation. However, the importance past features or temporal stability shaping structure remains undervalued, particularly birds. We assessed – derived from attributes measures –, comparison to isolation, as drivers differentiation Iberian bluethroat ( Luscinia svecica azuricollis ), migratory whose populations breed fragmented dynamic landscapes affected land use change. First, we characterized using microsatellite genotypes evaluated distances. Then, built species distribution models predictor time series (two decades) values Normalized Difference Vegetation Index proxies recent ultimately generate through different functions. Finally, used maximum‐likelihood effects evaluate relationships between distances found four clusters bluethroats populations, well high level Genetic was better associated with resistance, rather than distance. The highest habitat suitability corresponded areas where vegetation remained mostly stable during two decades prior surveys, low annual precipitation spring temperature, being relationship gene flow presence intervenient among linear quasi‐linear. Our results suggest that conservation policies management practices promote maintenance semi‐open pasture‐shrub mosaics (e.g. extensive livestock grazing) can strongly benefit improving connectivity.

Language: Английский

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Sperm morphology and performance in relation to postmating prezygotic isolation in two recently diverged passerine species

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Dec. 24, 2022

Abstract Divergence in sperm phenotype and female reproductive environment may be a common source of postmating prezygotic (PMPZ) isolation between species. However, compared to other barriers it has received much less attention. In this study, we examined morphology velocity two hybridizing passerine species, the nightingale ( Luscinia megarhynchos ) thrush L. luscinia ). addition, for first time characterized tract fluid proteome. We demonstrate that spermatozoa have significantly longer wider midpiece (proximal part flagellum containing mitochondria) tail nightingale. On hand, they shorter narrower acrosome. Importantly, these differences did not any effect on velocity. Furthermore, from females differentially affect conspecific heterospecific sperm. Our results indicate observed changes acrosome size are unlikely contribute PMPZ through differential tract. could postcopulatory processes, which might involved isolation, such as storage, longevity or sperm-egg interaction.

Language: Английский

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Social dominance explains within-ejaculate variation in sperm design in a passerine bird

BMC Evolutionary Biology, Journal Year: 2017, Volume and Issue: 17(1)

Published: March 4, 2017

Comparative studies suggest that sperm competition exerts stabilizing selection towards an optimal design - e.g., the relative size and covariation of different sections or a quantitative measure shape maximizes male fertility, which results in reduced levels within-male variation morphology. Yet, these also reveal substantial amounts unexplained within-ejaculate variance, factors presiding to maintenance such at population level still remain be identified. Sperm models predict males should progressively invest more resources their germline as mating costs increase, i.e., soma/germline allocation trade-off hypothesis. When access fertile females is determined by social dominance, hypothesis predicts dominant less control spermatogenesis. Hence, dominance positively correlate with variance design.In support this hypothesis, we found house sparrow produce ejaculates higher compared subordinate males. However, after experimentally manipulating status, pattern was not maintained.Our might according status some extent. it seems cannot rapidly adjusted new status. While could result from various non-exclusive sources, discuss how strategic somatic vs. functions important process shaping relationship between

Language: Английский

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