{"title":"Barcelona to Host ESEB 2025: Europe's Premier Evolutionary Biology Congress.","authors":"","doi":"10.1093/jeb/voae054","DOIUrl":"10.1093/jeb/voae054","url":null,"abstract":"","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141477866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Double-strand breaks (DSB), the most difficult to repair DNA damage, are mainly repaired by non-homologous end-joining (NHEJ) or homologous recombination (HR). Previous studies seem to indicate that primates, and particularly humans, have a better NHEJ system. A distinctive feature of the primate lineage (beside longevity) is encephalization, i.e., the expansion of the brain relative to body mass (BM). Using existing transcriptome data from 34 mammalian species, we investigated the possible correlations between the expression of genes involved in NHEJ and encephalization, BM, and longevity. The same was done also for genes involved in the HR pathway. We found that, while HR gene expression is better correlated with longevity, NHEJ gene expression is strongly (and better) correlated with encephalization. Since the brain is composed of postmitotic cells, DSB repair should be mainly performed by NHEJ in this organ. Therefore, we interpret the correlation we found as an indication that NHEJ efficiency coevolved with encephalization.
{"title":"Coevolution of non-homologous end joining efficiency and encephalization.","authors":"Ion Udroiu, Antonella Sgura","doi":"10.1093/jeb/voae057","DOIUrl":"10.1093/jeb/voae057","url":null,"abstract":"<p><p>Double-strand breaks (DSB), the most difficult to repair DNA damage, are mainly repaired by non-homologous end-joining (NHEJ) or homologous recombination (HR). Previous studies seem to indicate that primates, and particularly humans, have a better NHEJ system. A distinctive feature of the primate lineage (beside longevity) is encephalization, i.e., the expansion of the brain relative to body mass (BM). Using existing transcriptome data from 34 mammalian species, we investigated the possible correlations between the expression of genes involved in NHEJ and encephalization, BM, and longevity. The same was done also for genes involved in the HR pathway. We found that, while HR gene expression is better correlated with longevity, NHEJ gene expression is strongly (and better) correlated with encephalization. Since the brain is composed of postmitotic cells, DSB repair should be mainly performed by NHEJ in this organ. Therefore, we interpret the correlation we found as an indication that NHEJ efficiency coevolved with encephalization.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140912645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eva J P Lievens, Samuel Kühn, Elena L Horas, Guénolé Le Pennec, Sarah Peter, Azade D Petrosky, Sven Künzel, Philine G D Feulner, Lutz Becks
Arms race dynamics are a common outcome of host-parasite coevolution. While they can theoretically be maintained indefinitely, realistic arms races are expected to be finite. Once an arms race has ended, for example due to the evolution of a generalist-resistant host, the system may transition into coevolutionary dynamics that favour long-term diversity. In microbial experiments, host-parasite arms races often transition into a stable coexistence of generalist-resistant hosts, (semi-)susceptible hosts, and parasites. While long-term host diversity is implicit in these cases, parasite diversity is usually overlooked. In this study, we examined parasite diversity after the end of an experimental arms race between a unicellular alga (Chlorella variabilis) and its lytic virus (PBCV-1). First, we isolated virus genotypes from multiple time points from two replicate microcosms. A time-shift experiment confirmed that the virus isolates had escalating host ranges, i.e., that arms races had occurred. We then examined the phenotypic and genetic diversity of virus isolates from the post-arms race phase. Post-arms race virus isolates had diverse host ranges, survival probabilities, and growth rates; they also clustered into distinct genetic groups. Importantly, host range diversity was maintained throughout the post-arms race phase, and the frequency of host range phenotypes fluctuated over time. We hypothesize that this dynamic polymorphism was maintained by a combination of fluctuating selection and demographic stochasticity. Together with previous work in prokaryotic systems, our results link experimental observations of arms races to natural observations of long-term host and parasite diversity.
{"title":"High parasite diversity maintained after an alga-virus coevolutionary arms race.","authors":"Eva J P Lievens, Samuel Kühn, Elena L Horas, Guénolé Le Pennec, Sarah Peter, Azade D Petrosky, Sven Künzel, Philine G D Feulner, Lutz Becks","doi":"10.1093/jeb/voae053","DOIUrl":"10.1093/jeb/voae053","url":null,"abstract":"<p><p>Arms race dynamics are a common outcome of host-parasite coevolution. While they can theoretically be maintained indefinitely, realistic arms races are expected to be finite. Once an arms race has ended, for example due to the evolution of a generalist-resistant host, the system may transition into coevolutionary dynamics that favour long-term diversity. In microbial experiments, host-parasite arms races often transition into a stable coexistence of generalist-resistant hosts, (semi-)susceptible hosts, and parasites. While long-term host diversity is implicit in these cases, parasite diversity is usually overlooked. In this study, we examined parasite diversity after the end of an experimental arms race between a unicellular alga (Chlorella variabilis) and its lytic virus (PBCV-1). First, we isolated virus genotypes from multiple time points from two replicate microcosms. A time-shift experiment confirmed that the virus isolates had escalating host ranges, i.e., that arms races had occurred. We then examined the phenotypic and genetic diversity of virus isolates from the post-arms race phase. Post-arms race virus isolates had diverse host ranges, survival probabilities, and growth rates; they also clustered into distinct genetic groups. Importantly, host range diversity was maintained throughout the post-arms race phase, and the frequency of host range phenotypes fluctuated over time. We hypothesize that this dynamic polymorphism was maintained by a combination of fluctuating selection and demographic stochasticity. Together with previous work in prokaryotic systems, our results link experimental observations of arms races to natural observations of long-term host and parasite diversity.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140855782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to: Revisiting the number of self-incompatibility alleles in finite populations: From old models to new results.","authors":"","doi":"10.1093/jeb/voae059","DOIUrl":"10.1093/jeb/voae059","url":null,"abstract":"","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141175860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Francesca Santostefano, Maxime Fraser Franco, Pierre-Olivier Montiglio
Understanding the influence of social interactions on individual fitness is key to improving our predictions of phenotypic evolution. However, we often overlook the different components of selection regimes arising from interactions among organisms, including social, correlational, and indirect selection. This is due to the challenging sampling efforts required in natural populations to measure phenotypes expressed during interactions and individual fitness. Furthermore, behaviours are crucial in mediating social interactions, yet few studies have explicitly quantified these selection components on behavioural traits. In this study, we capitalize on an online multiplayer video game as a source of extensive data recording direct social interactions among prey, where prey collaborate to escape a predator in realistic ecological settings. We estimate natural and social selection and their contribution to total selection on behavioural traits mediating competition, cooperation, and predator-prey interactions. Behaviours of other prey in a group impact an individual's survival, and thus are under social selection. Depending on whether selection pressures on behaviours are synergistic or conflicting, social interactions enhance or mitigate the strength of natural selection, although natural selection remains the main driving force. Indirect selection through correlations among traits also contributed to the total selection. Thus, failing to account for the effects of social interactions and indirect selection would lead to a misestimation of the total selection acting on traits. Dissecting the contribution of each component to the total selection differential allowed us to investigate the causal mechanisms relating behaviour to fitness and quantify the importance of the behaviours of conspecifics as agents of selection. Our study emphasizes that social interactions generate complex selective regimes even in a relatively simple ecological environment.
{"title":"Social interactions generate complex selection patterns in virtual worlds.","authors":"Francesca Santostefano, Maxime Fraser Franco, Pierre-Olivier Montiglio","doi":"10.1093/jeb/voae055","DOIUrl":"10.1093/jeb/voae055","url":null,"abstract":"<p><p>Understanding the influence of social interactions on individual fitness is key to improving our predictions of phenotypic evolution. However, we often overlook the different components of selection regimes arising from interactions among organisms, including social, correlational, and indirect selection. This is due to the challenging sampling efforts required in natural populations to measure phenotypes expressed during interactions and individual fitness. Furthermore, behaviours are crucial in mediating social interactions, yet few studies have explicitly quantified these selection components on behavioural traits. In this study, we capitalize on an online multiplayer video game as a source of extensive data recording direct social interactions among prey, where prey collaborate to escape a predator in realistic ecological settings. We estimate natural and social selection and their contribution to total selection on behavioural traits mediating competition, cooperation, and predator-prey interactions. Behaviours of other prey in a group impact an individual's survival, and thus are under social selection. Depending on whether selection pressures on behaviours are synergistic or conflicting, social interactions enhance or mitigate the strength of natural selection, although natural selection remains the main driving force. Indirect selection through correlations among traits also contributed to the total selection. Thus, failing to account for the effects of social interactions and indirect selection would lead to a misestimation of the total selection acting on traits. Dissecting the contribution of each component to the total selection differential allowed us to investigate the causal mechanisms relating behaviour to fitness and quantify the importance of the behaviours of conspecifics as agents of selection. Our study emphasizes that social interactions generate complex selective regimes even in a relatively simple ecological environment.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140861043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Domains as functional protein units and their rearrangements along the phylogeny can shed light on the functional changes of proteomes associated with the evolution of complex traits like eusociality. This complex trait is associated with sterile soldiers and workers, and long-lived, highly fecund reproductives. Unlike in Hymenoptera (ants, bees, and wasps), the evolution of eusociality within Blattodea, where termites evolved from within cockroaches, was accompanied by a reduction in proteome size, raising the question of whether functional novelty was achieved with existing rather than novel proteins. To address this, we investigated the role of domain rearrangements during the evolution of termite eusociality. Analysing domain rearrangements in the proteomes of three solitary cockroaches and five eusocial termites, we inferred more than 5,000 rearrangements over the phylogeny of Blattodea. The 90 novel domain arrangements that emerged at the origin of termites were enriched for several functions related to longevity, such as protein homeostasis, DNA repair, mitochondrial activity, and nutrient sensing. Many domain rearrangements were related to changes in developmental pathways, important for the emergence of novel castes. Along with the elaboration of social complexity, including permanently sterile workers and larger, foraging colonies, we found 110 further domain arrangements with functions related to protein glycosylation and ion transport. We found an enrichment of caste-biased expression and splicing within rearranged genes, highlighting their importance for the evolution of castes. Furthermore, we found increased levels of DNA methylation among rearranged compared to non-rearranged genes suggesting fundamental differences in their regulation. Our findings indicate the importance of domain rearrangements in the generation of functional novelty necessary for termite eusociality to evolve.
作为蛋白质功能单元的结构域及其在系统发育过程中的重新排列,可以揭示蛋白质组的功能变化与复杂性状(如群居性)的进化有关。这种复杂的性状与不育的士兵和工人以及寿命长、繁殖力强的生殖者有关。与姬蜂目(蚂蚁、蜜蜂和黄蜂)不同,白蚁目(白蚁从蟑螂内部进化而来)的蚁群进化伴随着蛋白质组规模的缩小,这就提出了一个问题:功能新颖性是否是通过现有蛋白质而不是新蛋白质实现的?为了解决这个问题,我们研究了白蚁社会性进化过程中结构域重排的作用。通过分析三只独居蟑螂和五只群居白蚁蛋白质组中的结构域重排,我们推断出白蚁系统发育过程中的5000多次结构域重排。白蚁起源时出现的90个新的结构域排列富含与长寿有关的几种功能,如蛋白质稳态、DNA修复、线粒体活动和营养传感。许多结构域的重新排列与发育途径的变化有关,这对新种姓的出现非常重要。随着社会复杂性的发展,包括永久不育的工蚁和更大的觅食群落,我们又发现了 110 个与蛋白质糖基化和离子转运功能有关的结构域排列。我们发现,在重新排列的基因中,种姓偏向的表达和剪接都很丰富,这凸显了它们对种姓进化的重要性。此外,我们还发现重排基因的 DNA 甲基化水平高于非重排基因,这表明重排基因的调控存在根本性差异。我们的研究结果表明了白蚁社会性进化所需的功能新颖性产生过程中域重排的重要性。
{"title":"Major changes in domain arrangements are associated with the evolution of termites.","authors":"Alina A Mikhailova, Elias Dohmen, Mark C Harrison","doi":"10.1093/jeb/voae047","DOIUrl":"10.1093/jeb/voae047","url":null,"abstract":"<p><p>Domains as functional protein units and their rearrangements along the phylogeny can shed light on the functional changes of proteomes associated with the evolution of complex traits like eusociality. This complex trait is associated with sterile soldiers and workers, and long-lived, highly fecund reproductives. Unlike in Hymenoptera (ants, bees, and wasps), the evolution of eusociality within Blattodea, where termites evolved from within cockroaches, was accompanied by a reduction in proteome size, raising the question of whether functional novelty was achieved with existing rather than novel proteins. To address this, we investigated the role of domain rearrangements during the evolution of termite eusociality. Analysing domain rearrangements in the proteomes of three solitary cockroaches and five eusocial termites, we inferred more than 5,000 rearrangements over the phylogeny of Blattodea. The 90 novel domain arrangements that emerged at the origin of termites were enriched for several functions related to longevity, such as protein homeostasis, DNA repair, mitochondrial activity, and nutrient sensing. Many domain rearrangements were related to changes in developmental pathways, important for the emergence of novel castes. Along with the elaboration of social complexity, including permanently sterile workers and larger, foraging colonies, we found 110 further domain arrangements with functions related to protein glycosylation and ion transport. We found an enrichment of caste-biased expression and splicing within rearranged genes, highlighting their importance for the evolution of castes. Furthermore, we found increased levels of DNA methylation among rearranged compared to non-rearranged genes suggesting fundamental differences in their regulation. Our findings indicate the importance of domain rearrangements in the generation of functional novelty necessary for termite eusociality to evolve.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140873973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sperm competition is a potent mechanism of postcopulatory sexual selection that has been found to shape reproductive morphologies and behaviours in promiscuous animals. Especially sperm size has been argued to evolve in response to sperm competition through its effect on sperm longevity, sperm motility, the ability to displace competing sperm, and ultimately fertilization success. Additionally, sperm size has been observed to co-evolve with female reproductive morphology. Theoretical work predicts that sperm competition may select for longer sperm but may also favour shorter sperm if sperm size trades-off with number. In this study, we studied the relationship between sperm size and postmating success in the free-living flatworm, Macrostomum lignano. Specifically, we used inbred isolines of M. lignano that varied in sperm size to investigate how sperm size translated into the ability of worms to transfer and deposit sperm in a mating partner. Our results revealed a hump-shaped relationship with individuals producing sperm of intermediate size having the highest sperm competitiveness. This finding broadens our understanding of the evolution of sperm morphology by providing empirical support for stabilizing selection on sperm size under sperm competition.
{"title":"Sperm competition favours intermediate sperm size in a hermaphrodite1.","authors":"Santhosh Santhosh, Dieter Ebert, Tim Janicke","doi":"10.1093/jeb/voae058","DOIUrl":"10.1093/jeb/voae058","url":null,"abstract":"<p><p>Sperm competition is a potent mechanism of postcopulatory sexual selection that has been found to shape reproductive morphologies and behaviours in promiscuous animals. Especially sperm size has been argued to evolve in response to sperm competition through its effect on sperm longevity, sperm motility, the ability to displace competing sperm, and ultimately fertilization success. Additionally, sperm size has been observed to co-evolve with female reproductive morphology. Theoretical work predicts that sperm competition may select for longer sperm but may also favour shorter sperm if sperm size trades-off with number. In this study, we studied the relationship between sperm size and postmating success in the free-living flatworm, Macrostomum lignano. Specifically, we used inbred isolines of M. lignano that varied in sperm size to investigate how sperm size translated into the ability of worms to transfer and deposit sperm in a mating partner. Our results revealed a hump-shaped relationship with individuals producing sperm of intermediate size having the highest sperm competitiveness. This finding broadens our understanding of the evolution of sperm morphology by providing empirical support for stabilizing selection on sperm size under sperm competition.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140912686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arnaud Le Rouzic, Marie Roumet, Alex Widmer, Josselin Clo
The contribution of non-additive genetic effects to the genetic architecture of fitness and to the evolutionary potential of populations has been a topic of theoretical and empirical interest for a long time. Yet, the empirical study of these effects in natural populations remains scarce, perhaps because measuring dominance and epistasis relies heavily on experimental line crosses. In this study, we explored the contribution of dominance and epistasis in natural alpine populations of Arabidopsis thaliana for 2 fitness traits, the dry biomass and the estimated number of siliques, measured in a greenhouse. We found that, on average, crosses between inbred lines of A. thaliana led to mid-parent heterosis for dry biomass but outbreeding depression for an estimated number of siliques. While heterosis for dry biomass was due to dominance, we found that outbreeding depression for an estimated number of siliques could be attributed to the breakdown of beneficial epistatic interactions. We simulated and discussed the implication of these results for the adaptive potential of the studied populations, as well as the use of line-cross analyses to detect non-additive genetic effects.
{"title":"Detecting directional epistasis and dominance from cross-line analyses in alpine populations of Arabidopsis thaliana.","authors":"Arnaud Le Rouzic, Marie Roumet, Alex Widmer, Josselin Clo","doi":"10.1093/jeb/voae056","DOIUrl":"10.1093/jeb/voae056","url":null,"abstract":"<p><p>The contribution of non-additive genetic effects to the genetic architecture of fitness and to the evolutionary potential of populations has been a topic of theoretical and empirical interest for a long time. Yet, the empirical study of these effects in natural populations remains scarce, perhaps because measuring dominance and epistasis relies heavily on experimental line crosses. In this study, we explored the contribution of dominance and epistasis in natural alpine populations of Arabidopsis thaliana for 2 fitness traits, the dry biomass and the estimated number of siliques, measured in a greenhouse. We found that, on average, crosses between inbred lines of A. thaliana led to mid-parent heterosis for dry biomass but outbreeding depression for an estimated number of siliques. While heterosis for dry biomass was due to dominance, we found that outbreeding depression for an estimated number of siliques could be attributed to the breakdown of beneficial epistatic interactions. We simulated and discussed the implication of these results for the adaptive potential of the studied populations, as well as the use of line-cross analyses to detect non-additive genetic effects.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140868095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jade Castel, Florence Pradillon, Valérie Cueff, Guillaume Leger, Claire Daguin-Thiébaut, Stéphanie Ruault, Jean Mary, Stéphane Hourdez, Didier Jollivet, Thomas Broquet
Molluscs have undergone many transitions between separate sexes and hermaphroditism, which is of interest in studying the evolution of sex determination and differentiation. Here, we combined multi-locus genotypes obtained from restriction site-associated DNA (RAD) sequencing with anatomical observations of the gonads of three deep-sea hydrothermal vent gastropods of the genus Alviniconcha living in the southwest Pacific. We found that all three species (Alviniconcha boucheti, Alviniconcha strummeri, and Alviniconcha kojimai) share the same male-heterogametic XY sex-determination system but that the gonads of XX A. kojimai individuals are invaded by a variable proportion of male reproductive tissue. The identification of Y-specific RAD loci (found only in A. boucheti) and the phylogenetic analysis of three sex-linked loci shared by all species suggested that X-Y recombination has evolved differently within each species. This situation of three species showing variation in gonadal development around a common sex-determination system provides new insights into the reproductive mode of poorly known deep-sea species and opens up an opportunity to study the evolution of recombination suppression on sex chromosomes and its association with mixed or transitory sexual systems.
软体动物在两性分离和雌雄同体之间经历了多次转变,这对研究性别决定和分化的演化很有意义。在这里,我们将 RAD 测序获得的多焦点基因型与性腺解剖观察相结合,研究了生活在西南太平洋的三种深海热液喷口腹足纲阿尔文尼孔查属动物。我们发现所有三个物种(A. boucheti、A. strummeri 和 A. kojimai)都具有相同的雄性异配 XY 性别决定系统,但 XX A. kojimai 个体的性腺被不同比例的雄性生殖组织侵占。对 Y 特异性 RAD 位点的鉴定(仅在 A. boucheti 发现)和对所有物种共有的三个性连锁位点的系统进化分析表明,X-Y 重组在每个物种内部都有不同的进化。围绕一个共同的性别决定系统,三个物种的性腺发育出现了差异,这种情况为人们了解鲜为人知的深海物种的繁殖模式提供了新的视角,并为研究性染色体上重组抑制的进化及其与混合性系统或过渡性系统的关系提供了机会。
{"title":"Genetic sex determination in three closely related hydrothermal vent gastropods, including one species with intersex individuals.","authors":"Jade Castel, Florence Pradillon, Valérie Cueff, Guillaume Leger, Claire Daguin-Thiébaut, Stéphanie Ruault, Jean Mary, Stéphane Hourdez, Didier Jollivet, Thomas Broquet","doi":"10.1093/jeb/voae051","DOIUrl":"10.1093/jeb/voae051","url":null,"abstract":"<p><p>Molluscs have undergone many transitions between separate sexes and hermaphroditism, which is of interest in studying the evolution of sex determination and differentiation. Here, we combined multi-locus genotypes obtained from restriction site-associated DNA (RAD) sequencing with anatomical observations of the gonads of three deep-sea hydrothermal vent gastropods of the genus Alviniconcha living in the southwest Pacific. We found that all three species (Alviniconcha boucheti, Alviniconcha strummeri, and Alviniconcha kojimai) share the same male-heterogametic XY sex-determination system but that the gonads of XX A. kojimai individuals are invaded by a variable proportion of male reproductive tissue. The identification of Y-specific RAD loci (found only in A. boucheti) and the phylogenetic analysis of three sex-linked loci shared by all species suggested that X-Y recombination has evolved differently within each species. This situation of three species showing variation in gonadal development around a common sex-determination system provides new insights into the reproductive mode of poorly known deep-sea species and opens up an opportunity to study the evolution of recombination suppression on sex chromosomes and its association with mixed or transitory sexual systems.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140873482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sexual conflict plays a key role in the dynamics of adaptive evolution in sexually reproducing populations, and theory suggests an important role for variance in resource acquisition in generating or masking sexual conflict over fitness and life history traits. Here, I used a quantitative genetic genotype × environment experiment in Drosophila melanogaster to test the theoretical prediction that variance in resource acquisition mediates variation in sex-specific component fitness. Holding larval conditions constant, I found that adult nutritional environments characterized by high protein content resulted in reduced survival of both sexes and lower male reproductive success compared to an environment of lower protein content. Despite reduced mean fitness of both sexes in high protein environments, I found a sex*treatment interaction for the relationship between resource acquisition and fitness; estimates of the adaptive landscape indicate males were furthest from their optimum resource acquisition level in high protein environments, and females were furthest in low protein environments. Expression of genetic variance in resource acquisition and survival was highest for each sex in the environment it was best adapted to, although the treatment effects on expression of genetic variance eroded in the path from resource acquisition to total fitness. Cross-sex genetic correlations were strongly positive for resource acquisition, survival, and total fitness and negative for mating success, although estimation error was high for all. These results demonstrate that environmental effects on resource acquisition can have predictable consequences for the expression of sex-specific genetic variance but also that these effects of resource acquisition can erode through life history.
性冲突在有性繁殖种群的适应性进化动态中起着关键作用,而理论表明,资源获取的差异在产生或掩盖有关适应性和生活史特征的性冲突方面起着重要作用。在这里,我利用黑腹果蝇的定量遗传基因型 x 环境实验,验证了资源获取的差异介导性别特异性成分适应性差异的理论预测。在幼虫条件不变的情况下,我发现与蛋白质含量较低的环境相比,蛋白质含量高的成虫营养环境会导致雌雄果蝇的存活率降低,雄果蝇的繁殖成功率也会降低。尽管在高蛋白环境中雌雄个体的平均体能都有所下降,但我发现在资源获取和体能之间存在性别*处理的交互作用;对适应性景观的估计表明,在高蛋白环境中雄性个体离最佳资源获取水平最远,而在低蛋白环境中雌性个体离最佳资源获取水平最远。在最适应的环境中,每种性别在资源获取和存活方面的遗传变异表达都是最高的,尽管在从资源获取到总适应度的过程中,处理对遗传变异表达的影响会减弱。跨性别遗传相关性在资源获取、存活率和总适合度方面呈强正值,而在交配成功率方面呈负值,尽管所有相关性的估计误差都很大。这些结果表明,环境对资源获取的影响会对性别特异性遗传变异的表达产生可预测的后果,而且这些资源获取的影响会在整个生活史中逐渐消失。
{"title":"Genotype × Environment interaction and the evolution of sexual dimorphism: adult nutritional environment mediates selection and expression of sex-specific genetic variance in Drosophila melanogaster.","authors":"Stephen P De Lisle","doi":"10.1093/jeb/voae050","DOIUrl":"10.1093/jeb/voae050","url":null,"abstract":"<p><p>Sexual conflict plays a key role in the dynamics of adaptive evolution in sexually reproducing populations, and theory suggests an important role for variance in resource acquisition in generating or masking sexual conflict over fitness and life history traits. Here, I used a quantitative genetic genotype × environment experiment in Drosophila melanogaster to test the theoretical prediction that variance in resource acquisition mediates variation in sex-specific component fitness. Holding larval conditions constant, I found that adult nutritional environments characterized by high protein content resulted in reduced survival of both sexes and lower male reproductive success compared to an environment of lower protein content. Despite reduced mean fitness of both sexes in high protein environments, I found a sex*treatment interaction for the relationship between resource acquisition and fitness; estimates of the adaptive landscape indicate males were furthest from their optimum resource acquisition level in high protein environments, and females were furthest in low protein environments. Expression of genetic variance in resource acquisition and survival was highest for each sex in the environment it was best adapted to, although the treatment effects on expression of genetic variance eroded in the path from resource acquisition to total fitness. Cross-sex genetic correlations were strongly positive for resource acquisition, survival, and total fitness and negative for mating success, although estimation error was high for all. These results demonstrate that environmental effects on resource acquisition can have predictable consequences for the expression of sex-specific genetic variance but also that these effects of resource acquisition can erode through life history.</p>","PeriodicalId":50198,"journal":{"name":"Journal of Evolutionary Biology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140856791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}