The Experts below are selected from a list of 9675 Experts worldwide ranked by ideXlab platform
Joachim Hermisson - One of the best experts on this subject based on the ideXlab platform.
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the limits to parapatric speciation ii strengthening a preexisting Genetic barrier to gene flow in parapatry
2018Co-Authors: Joachim Hermisson, Alexandre BlanckaertAbstract:By encompassing the whole continuum between allopatric and sympatric scenarios, parapatric speciation includes many potential scenarios for the evolution of new species. Here, we investigate how a Genetic barrier to gene flow, that relies on a single postzygotic Genetic Incompatibility, may further evolve under ongoing migration. We consider a continent island model with three loci involved in pairwise Dobzhansky–Muller incompatibilities (DMIs). Using an analytic approach, we derive the conditions for invasion of a new mutation and its consequences for the strength and stability of the initial Genetic barrier. Our results show that the accumulation of Genetic incompatibilities in the presence of gene flow is under strong selective constraints. In particular, preexisting incompatibilities do not always facilitate the invasion of further barrier genes. If new mutations do invade, they will often weaken or destroy the barrier rather than strengthening it. We conclude that migration is highly effective at disrupting the so-called “snowball effect”, the accelerated accumulation of DMIs that has been described for allopatric populations en route to reproductive isolation.
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the limits to parapatric speciation ii strengthening a preexisting Genetic barrier to gene flow in parapatry
2018Co-Authors: Alexandre Blanckaert, Joachim HermissonAbstract:Parapatric speciation has recently received a lot of attention. By encompassing the whole continuum between allopatric and sympatric scenarios, it includes many potential scenarios for the evolution of new species. Building upon previous work, we investigate how a Genetic barrier to gene flow, that relies on a single postzygotic Genetic Incompatibility, may further evolve. We consider a continent island model with three loci involved in pairwise Dobzhansky-Muller incompatibilities (DMIs). Using a deterministic and analytic approach, we derive the conditions for invasion of a new mutation and its consequences on an already existing Genetic barrier to gene flow. We focus on quantifying the impact of the epistasis generated by the new mutation on the Genetic barrier. We show that the accumulation of Genetic incompatibilities in the presence of gene flow is a complex process, where new mutations can either strengthen or destroy a preexisting barrier. In particular, preexisting polymorphism and incompatibilities do not always facilitate the growth of the Genetic barrier by accumulation of further barrier genes. Migration may disrupt the snowball effect (the accelerating rate of DMI accumulation in allopatry) because incompatibilities are directly tested by selection. Our results also show an ambiguous role of gene flow, which can either impede or facilitate the strengthening of the Genetic barrier. Overall, our results illustrate how the inclusion of gene flow renders the building of a Genetic barrier difficult to analyze.
Leigh W Simmons - One of the best experts on this subject based on the ideXlab platform.
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paternal indirect Genetic effects on offspring viability and the benefits of polyandry
2007Co-Authors: Francisco Garciagonzalez, Leigh W SimmonsAbstract:Summary Although females are expected to maximize their reproductive success with only one or a few matings [1], the females of many species mate with multiple partners [2]. Experimental studies have found evidence for an increase in egg or embryo viability when females mate polyandrously [3]. These studies have been interpreted in the context of Genetic-benefit models that propose that multiple mating increases offspring viability because it allows females to select male genotypes that influence viability directly or because it allows females to avoid Genetic Incompatibility [2, 4–8]. However, no studies have examined directly the precise mechanisms by which parents influence embryo viability. Using a morphological marker that enabled us to determine paternity and survival of embryos sired by individual male crickets in both sperm-competitive and -noncompetitive situations, we show that males inducing high embryo viability enhance the viability of embryos sired by inferior males. These results indicate that paternal effects and interacting phenotypes determine embryo viability. They show that a male's reproductive success is modified by the interaction between indirect Genetic effects of sperm competitors. Importantly, our findings show that the benefits accruing to offspring of multiply mated females need not be transmitted Genetically.
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the evolution of polyandry sperm competition sperm selection and offspring viability
2005Co-Authors: Leigh W SimmonsAbstract:▪ Abstract In contrast to Bateman's principle, there is now increasing evidence that female fitness can depend on the number of mates obtained. A number of Genetic benefits have been proposed for the evolution of polyandry. A meta-analysis of available data suggests that polyandry, rather than multiple mating, can have a weak but significant general effect on embryo viability, as indicated by egg hatching success. Although this effect is generally regarded as evidence in favor of the Genetic Incompatibility hypothesis, appropriate data that test for intrinsic sire effects on embryo viability are generally unavailable. Moreover, maternal effects that could generate the result have not been adequately controlled, and there is little unequivocal evidence to suggest that fertilization is biased toward sperm bearing genotypes that would enhance offspring viability. Greater effort is required in these areas to elucidate the mechanisms underlying observed fitness effects of polyandry.
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the evolution of polyandry an examination of the Genetic Incompatibility and good sperm hypotheses
2001Co-Authors: Leigh W SimmonsAbstract:I have examined the adaptive significance of polyandry using the Australian field cricket Teleogryllus oceanicus. Previous studies of polyandry have examined differences in offspring production by females mated multiply to a single male or females mated multiply to different males. Here I combine this approach with a study of parentage of offspring produced in the later group. Females mated to two different males had a higher proportion of their eggs hatching than did females mating twice with a single male. Offspring fitness parameters were not effected. There was little evidence to suggest that females elevate their hatching success via fertilizing their eggs with sperm from Genetically compatible males. Although the average paternity points towards random sperm mixing, there was considerable individual variation in sperm competition success. Patterns of parentage were consistent across females mating twice or four times. Sperm competition success was not related to offspring viability or performance. Thus, the notion that competitively superior sperm produce competitively superior offspring is not supported either. The mechanism underlying increased hatching success with polyandry requires further study.
Maarten Koornneef - One of the best experts on this subject based on the ideXlab platform.
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the evolutionary dynamics of Genetic incompatibilities introduced by duplicated genes in arabidopsis thaliana
2021Co-Authors: Wenbiao Jiao, Christine Camilleri, Vipul Patel, Jonas R Klasen, Fang Liu, Petra Pecinkova, Marina Ferrand, Sigi Effgen, Maarten KoornneefAbstract:Although gene duplications provide Genetic backup and allow genomic changes under relaxed selection, they may potentially limit gene flow. When different copies of a duplicated gene are pseudofunctionalized in different genotypes, Genetic incompatibilities can arise in their hybrid offspring. Although such cases have been reported after manual crosses, it remains unclear whether they occur in nature and how they affect natural populations. Here, we identified four duplicated-gene based incompatibilities including one previously not reported within an artificial Arabidopsis intercross population. Unexpectedly, however, for each of the Genetic incompatibilities we also identified the incompatible alleles in natural populations based on the genomes of 1,135 Arabidopsis accessions published by the 1001 Genomes Project. Using the presence of incompatible allele combinations as phenotypes for GWAS, we mapped genomic regions that included additional gene copies which likely rescue the Genetic Incompatibility. Reconstructing the geographic origins and evolutionary trajectories of the individual alleles suggested that incompatible alleles frequently coexist, even in geographically closed regions, and that their effects can be overcome by additional gene copies collectively shaping the evolutionary dynamics of duplicated genes during population history.
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the evolutionary dynamics of Genetic incompatibilities introduced by duplicated genes in arabidopsis thaliana
2020Co-Authors: Wenbiao Jiao, Christine Camilleri, Vipul Patel, Jonas R Klasen, Fang Liu, Petra Pecinkova, Marina Ferrand, Sigi Effgen, Maarten KoornneefAbstract:Abstract Although gene duplications provide Genetic backup and allow genomic changes under relaxed selection, they may potentially limit gene flow. When different copies of a duplicated gene are pseudo-functionalized in different genotypes, Genetic incompatibilities can arise in their hybrid offspring. While such cases have been reported after manual crosses, it remains unclear whether they occur in nature and how they affect natural populations. Here we identified four duplicated-gene based incompatibilities including one previously not reported within an artificial Arabidopsis intercross population. Unexpectedly, however, for each of the Genetic incompatibilities we also identified the incompatible alleles in natural populations based on the genomes of 1,135 Arabidopsis accessions published by the 1001 Genomes Project. Using the presence of incompatible allele combinations as phenotypes for GWAS, we mapped genomic regions which included additional gene copies which likely rescue the Genetic Incompatibility. Reconstructing the geographic origins and evolutionary trajectories of the individual alleles suggested that incompatible alleles frequently co-exist, even in geographically closed regions, and that their effects can be overcome by additional gene copies collectively shaping the evolutionary dynamics of duplicated genes during population history.
Emmanuel Desouhant - One of the best experts on this subject based on the ideXlab platform.
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consequences of Genetic Incompatibility on fitness and mate choice the male point of view
2015Co-Authors: Anna Chuine, Sandrine Sauzet, Francois Debias, Emmanuel DesouhantAbstract:Hymenopterans under single-locus complementary sex determination (sl-CSD) face inbreeding costs due to this sex determination mode. Under sl-CSD, homozygote eggs at the sl-CSD locus usually develop into unviable or sterile diploid males. Production of such costly males increases when sib-mating happens because related individuals share half of their genome. In the hymenopteran Venturia canescens (a solitary parasitoid wasp), diploid males are sterile, leading to fitness costs through Genetic Incompatibility between parents. Whereas the costs of producing diploid males and behavioural strategies that would reduce such costs have been studied in females, the potential fitness costs faced by males have not. Here, we aimed to investigate fitness costs that males endure after a single sib-mating and tested whether they have the ability to avoid sib-mating through kin recognition. Our results show that males have a reduced fitness (i.e. they produce fewer daughters) when mating with their sibs. We also show that males have the ability to distinguish between non-sib and sib females (i.e. kin). They use chemical marks emitted by the females to discriminate kin from non-kin. We discuss the evolution of kin recognition in males in the context of mate choice for Genetic compatibility. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114, 279–286.
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does kin recognition and sib mating avoidance limit the risk of Genetic Incompatibility in a parasitic wasp
2010Co-Authors: Marie Metzger, Carlos Bernstein, Thomas S Hoffmeister, Emmanuel DesouhantAbstract:Background: When some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their Genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination), and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness. Methods and Findings: In this paper, we tested the hypothesis of Genetic Incompatibility avoidance by investigating sibmating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In ‘‘no-choice’’ tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males. Conclusions: Our results are compatible with the Genetic Incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a ‘‘self-referent phenotype matching’’ mechanism.
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Does kin recognition and sib-mating avoidance limit the risk of Genetic Incompatibility in a parasitic wasp?
2010Co-Authors: Marie Metzger, Carlos Bernstein, Thomas S Hoffmeister, Emmanuel DesouhantAbstract:When some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their Genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination), and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness.In this paper, we tested the hypothesis of Genetic Incompatibility avoidance by investigating sib-mating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In "no-choice" tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males.Our results are compatible with the Genetic Incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a "self-referent phenotype matching" mechanism
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Does Kin Recognition and Sib-Mating Avoidance Limit the Risk of Genetic Incompatibility in a Parasitic Wasp?
2010Co-Authors: Marie Metzger, Carlos Bernstein, Thomas S Hoffmeister, Emmanuel DesouhantAbstract:Background: When some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their Genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination), and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness. Methods and Findings: In this paper, we tested the hypothesis of Genetic Incompatibility avoidance by investigating sibmating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In ‘‘no-choice’ ’ tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males. Conclusions: Our results are compatible with the Genetic Incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a ‘‘self-referent phenotyp
Alexandre Blanckaert - One of the best experts on this subject based on the ideXlab platform.
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the limits to parapatric speciation ii strengthening a preexisting Genetic barrier to gene flow in parapatry
2018Co-Authors: Joachim Hermisson, Alexandre BlanckaertAbstract:By encompassing the whole continuum between allopatric and sympatric scenarios, parapatric speciation includes many potential scenarios for the evolution of new species. Here, we investigate how a Genetic barrier to gene flow, that relies on a single postzygotic Genetic Incompatibility, may further evolve under ongoing migration. We consider a continent island model with three loci involved in pairwise Dobzhansky–Muller incompatibilities (DMIs). Using an analytic approach, we derive the conditions for invasion of a new mutation and its consequences for the strength and stability of the initial Genetic barrier. Our results show that the accumulation of Genetic incompatibilities in the presence of gene flow is under strong selective constraints. In particular, preexisting incompatibilities do not always facilitate the invasion of further barrier genes. If new mutations do invade, they will often weaken or destroy the barrier rather than strengthening it. We conclude that migration is highly effective at disrupting the so-called “snowball effect”, the accelerated accumulation of DMIs that has been described for allopatric populations en route to reproductive isolation.
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the limits to parapatric speciation ii strengthening a preexisting Genetic barrier to gene flow in parapatry
2018Co-Authors: Alexandre Blanckaert, Joachim HermissonAbstract:Parapatric speciation has recently received a lot of attention. By encompassing the whole continuum between allopatric and sympatric scenarios, it includes many potential scenarios for the evolution of new species. Building upon previous work, we investigate how a Genetic barrier to gene flow, that relies on a single postzygotic Genetic Incompatibility, may further evolve. We consider a continent island model with three loci involved in pairwise Dobzhansky-Muller incompatibilities (DMIs). Using a deterministic and analytic approach, we derive the conditions for invasion of a new mutation and its consequences on an already existing Genetic barrier to gene flow. We focus on quantifying the impact of the epistasis generated by the new mutation on the Genetic barrier. We show that the accumulation of Genetic incompatibilities in the presence of gene flow is a complex process, where new mutations can either strengthen or destroy a preexisting barrier. In particular, preexisting polymorphism and incompatibilities do not always facilitate the growth of the Genetic barrier by accumulation of further barrier genes. Migration may disrupt the snowball effect (the accelerating rate of DMI accumulation in allopatry) because incompatibilities are directly tested by selection. Our results also show an ambiguous role of gene flow, which can either impede or facilitate the strengthening of the Genetic barrier. Overall, our results illustrate how the inclusion of gene flow renders the building of a Genetic barrier difficult to analyze.