Evolution Letters最新文献

{"title":"Evolutionary trade-offs between intergenerational and transgenerational fitness effects.","authors":"Isaac Harris, Elizabeth M L Duxbury, Tracey Chapman, Simone Immler, Alexei A Maklakov","doi":"10.1093/evlett/qrag031","DOIUrl":"https://doi.org/10.1093/evlett/qrag031","url":null,"abstract":"<p><p>Intergenerational and transgenerational fitness effects can shape evolutionary processes. Theoretically, however, intergenerational and transgenerational effects can trade off with each other with profound consequences for evolutionary processes. Here, we show that beneficial intergenerational effects that increase offspring fitness can result in detrimental transgenerational effects that decrease great-grand offspring fitness. We combined theoretical modeling and experimental approaches to investigate multigenerational fitness trade-offs induced by larval starvation in <i>Caenorhabditis elegans</i>. We demonstrate that larval starvation triggers a cascading effect: starved individuals suffered marked fitness losses, their direct offspring enjoyed fitness gains in both starvation and ad libitum environments, but great-grand offspring paid fitness costs. Demographic simulation models revealed that genotypes exploiting this short-term intergenerational advantage outcompete rival genotypes despite the deferred transgenerational debt. Our findings demonstrate that adaptive intergenerational gains can be intrinsically linked to maladaptive transgenerational outcomes, challenging the assumption that transgenerational effects are inherently beneficial and highlighting the role of multigenerational trade-offs in evolution.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"534-544"},"PeriodicalIF":4.3,"publicationDate":"2026-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629237/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149117006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution under the city's shadow: reproductive divergence of urban and rural great tits revealed by a common garden experiment.","authors":"Laurine A Mathieu, Ségolène Delaitre, Emilie Favaro, Baptiste Chenet, Anne Charmantier, Samuel P Caro","doi":"10.1093/evlett/qrag030","DOIUrl":"https://doi.org/10.1093/evlett/qrag030","url":null,"abstract":"<p><p>Urbanisation profoundly alters natural habitats and reshapes many traits in wild species, including their reproduction. In birds, urban populations typically breed earlier and lay smaller clutches than their rural conspecifics, patterns usually attributed to warmer temperatures and lower food availability in cities. Yet, whether these differences reflect phenotypic plasticity or genetic change remains unclear. To disentangle environmental from genetic contributions, we conducted a common garden experiment with great tits (<i>Parus major</i>) originating from unincubated eggs collected in urban and forest habitats. Nestlings were hand-reared under identical conditions and, the following spring, paired by origin in breeding aviaries. We recorded laying date, clutch size, egg volume, and fertilisation success, and compared them with wild phenotypic distributions. Contrary to patterns in the wild, laying dates did not differ between urban- and forest-origin females, revealing a plastic adjustment of the onset of breeding to the environment. Egg size remained consistently smaller in urban-origin females across both conditions, pointing to a genetic divergence. No difference in fertilisation rate was found between individuals of urban and forest origin in the common garden. Finally, clutch size differences showed striking opposite patterns between experimental and wild birds: in the common garden urban-origin females laid larger, and not smaller, clutches than forest-origin females, suggesting a counter-gradient variation where genetic and environmental effects act in opposing directions on the phenotype. Overall, our study showcases how integrating experimental designs with field monitoring can uncover the hidden dynamics of urban adaptation, including cryptic evolution masked by environmental constraints in cities.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"521-533"},"PeriodicalIF":4.3,"publicationDate":"2026-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629229/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asynchrony of ageing among traits in a wild bird population.","authors":"Claire Lok Sze Tsui, Michael Briga, Jan Komdeur, Terry Burke, David S Richardson, Hannah L Dugdale","doi":"10.1093/evlett/qrag029","DOIUrl":"https://doi.org/10.1093/evlett/qrag029","url":null,"abstract":"<p><p>Ageing i.e., age-related changes in a trait, is a highly variable process. Studies have investigated variation in ageing among species and individuals, but little is yet understood about variation between traits. Evolutionary hypotheses argued that traits should age synchronously as selection should improve the trait that first senesces, therefore leading to trait synchrony. However, some past studies have demonstrated that traits do not senesce synchronously. We tested for the (a)synchrony of ageing across 13 reproductive, behavioral, physiological, and morphological traits in a population of wild Seychelles warblers (<i>Acrocephalus sechellensis</i>). We modeled ageing trajectories for each trait and quantified synchrony between traits with similar ageing trajectory shapes by comparing the onset and rate of ageing and running bivariate models to quantify covariation between traits. We found that five traits exhibited ageing while eight did not. Upon visual comparison of ageing trajectories, there were three groups of traits that shared ageing trajectories of the same shape. There was no support for synchronous ageing among any traits. Our study adds to growing evidence that ageing is asynchronous, and that the theory of synchronous ageing was erroneous. Our finding of senescence in direct fitness indices, such as survival and reproductive success but not in wing length or tarsus length gives weak support to newer evolutionary theories of asynchronous ageing stating that traits more strongly associated with fitness age faster.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"506-520"},"PeriodicalIF":4.3,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629235/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repeated evolution of convergent iridescence in closely related species of <i>Morpho</i> butterflies living in sympatry.","authors":"Joséphine Ledamoisel, Vincent Debat, Violaine Llaurens","doi":"10.1093/evlett/qrag028","DOIUrl":"https://doi.org/10.1093/evlett/qrag028","url":null,"abstract":"<p><p>The evolution of visual traits in closely related species living in sympatry is highly influenced by their ecological interactions: while sexual selection tends to promote the divergence of visual cues involved in mate choice, natural selection via predation may promote the convergence of dissuasive signals between prey species, especially in unpalatable or evasive prey. Here, we investigate the impact of sympatry on the evolution of the blue structural coloration in the wings of two closely related <i>Morpho</i> butterfly species across several localities throughout Central and South America. Dorsal iridescence might affect mate choice and species recognition, which should promote its local divergence among species. However, the bright flashes and dynamic color patterns produced by iridescence during flight might also increase survival by confusing predators and favoring escape. Such an effect might in turn lead to convergence in wing iridescence between evasive species occurring in sympatry, a phenomenon dubbed evasive mimicry. To test the effect of these putative antagonistic selective forces on visual cues evolution, we quantified the variation of the structural blue color displayed at 13 different combinations of illumination/observation angles, on the wings of 2 closely related <i>Morpho</i> species. We contrasted 10 sympatric and 11 allopatric locations and specifically compared the phenotypic distances between individuals from different species. Phenotypic distances between heterospecific pairs of individuals were significantly smaller in sympatry, suggesting local convergences of iridescence consistent with the expected pattern assuming evasive mimicry. Interestingly, sexual dimorphism was found between males and females, suggesting that the trade-off between natural and sexual selection on the evolution of iridescence might differ between sexes. Our results suggest that local predation pressures may promote repeated evolutionary convergence of structural coloration between evasive prey species living in sympatry.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"493-504"},"PeriodicalIF":4.3,"publicationDate":"2026-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629238/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A resurrection experiment reveals reduced adaptive potential in a common agricultural weed.","authors":"Sasha G D Bishop, John R Stinchcombe, Regina S Baucom","doi":"10.1093/evlett/qrag026","DOIUrl":"https://doi.org/10.1093/evlett/qrag026","url":null,"abstract":"<p><p>Adaptive evolution is critical to population responses under accelerating anthropogenic global change. Although theory and some empirical work suggest that contemporary rates of environmental change can be met by equally rapid evolutionary shifts, mismatches between expected and realized evolution remain common in natural systems. Using a resurrection approach, we demonstrate that the structure of genetic covariances among pollination and mating-system traits in the common morning glory (<i>Ipomoea purpurea</i>) is increasingly constraining evolutionary trajectories. Pollinator-attracting traits evolved or became more favored on a rapid time scale of less than 10 years, but genetic covariances between traits limited the adaptive rate and evolutionary trajectory of flowering phenology, a trait with widely recognized importance in adapting to climatic shifts. Our results show that changing patterns of genetic constraint can substantially reduce adaptive potential even when selection favors rapid trait evolution.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"451-462"},"PeriodicalIF":4.3,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629232/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early-life stress reduces senescence in the field for an indeterminately growing ectotherm.","authors":"Will Morgan, Hayley Cameron, Dustin Marshall","doi":"10.1093/evlett/qrag027","DOIUrl":"https://doi.org/10.1093/evlett/qrag027","url":null,"abstract":"<p><p>Theory predicts that aged-related declines in performance (senescence) depend on experiences during early life. Experimental field tests of this theory are rare: most manipulative studies have been done in the laboratory on short-lived invertebrates; while most field studies focus on longer-lived vertebrates and involve no experimental manipulation. Consequently, few studies manipulate early-life stress and test its effects on senescence in the field, especially in invertebrates. We manipulated early-life stress in the colonial marine bryozoan, <i>Bugula neritina</i>, by experimentally extending the larval period (an energetic stress), then monitored the survival, fecundity and growth of more than 500 individuals in the field across their lifetimes. We used these data to generate trajectories of actuarial and reproductive senescence and test how both components of ageing were affected by early-life stress. While colonial organisms with indeterminate growth such as <i>B. neritina</i> have been theorised to show negligible senescence, instead we saw strong declines in survival and reproductive output in the oldest individuals, regardless of early-life stress. We also found that adults originating from stressed larvae had lower fitness overall (in terms of lifetime reproductive success), but experienced weaker actuarial senescence. Our findings for reproductive senescence were more nuanced, with some evidence to suggest that early-life stress also decreases rates of reproductive senescence. Our study provides a rare demonstration of senescence for an invertebrate in the field and suggests that the relationship between life history and senescence may be more complex than has been anticipated.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"483-492"},"PeriodicalIF":4.3,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629228/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149117004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A standardised framework for classifying estimates of reproductive isolation.","authors":"Jonah M Walker, Christopher R Cooney, Jonna Kulmuni, Konrad Lohse, Joana I Meier, Richard M Merrill, Elizabeth Scordato, Carole M Smadja, Sonal Singhal, Roger K Butlin, Sean Stankowski","doi":"10.1093/evlett/qrag023","DOIUrl":"https://doi.org/10.1093/evlett/qrag023","url":null,"abstract":"<p><p>Understanding reproductive isolation (RI) between lineages is a central goal of speciation research. While the strength of RI has been estimated across a broad range of taxa, synthesizing these data remains challenging, partially because we lack a common language for classifying and reporting RI estimates. Here, we present the <i>Reproductive Isolation Ontology</i> (RIO), a structured framework designed to standardize the classification of RI estimates across most sexually reproducing organisms. The RIO comprises 3 interrelated domains, each organized into a nested hierarchy of classification terms. We demonstrate the utility of this approach and call for researchers to adopt and expand the RIO to facilitate the integration of speciation research.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"441-450"},"PeriodicalIF":4.3,"publicationDate":"2026-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629230/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Group size modulates kinship dynamics and selection on social traits.","authors":"Peng He, Michael N Weiss, Samuel Ellis, Daniel W Franks, Michael A Cant, Darren P Croft, Rufus A Johnstone","doi":"10.1093/evlett/qrag025","DOIUrl":"https://doi.org/10.1093/evlett/qrag025","url":null,"abstract":"<p><p>An individual's relatedness to its group may change with age due to demographic processes, and such kinship dynamics can shape age-linked social behaviors. Existing models, however, have focused almost exclusively on dispersal and mating, leaving the consequences of group size local variation unexplored. Here, we extend these models to incorporate such variation within a single, genetically connected meta-population. We then contrast predicted kinship dynamics and age-linked selection for helping/harming in coexisting smaller and larger groups in three typical social mammal systems characterized by distinct patterns of dispersal and mating, followed by exploring how group size local variation impacts female and male kinship dynamics across broader demographic contexts to clarify the population-genetic mechanisms. We show that, within the adult reproductive lifespans of these social systems, an individual's age-specific relatedness to others is higher, and changes faster (especially when younger), in smaller groups; consequently, smaller groups favor more extreme helping/harming (especially when younger)-in social system with bisexual philopatry with nonlocal mating (e.g., whales) that favors female shifts from harming to helping with age (which explains the evolution of menopause and postreproductive helping), such shifts are earlier in smaller groups. Further explorations suggest that, in a genetically connected population with group size local variation, group size effects on local relatedness are shaped by the relative strengths of ancestry dilution versus lineage coalescence, and kinship dynamics in a group reflect not only its local demographic conditions, but also those in coexisting groups of different size. Collectively, our study generates new insights into how female and male kinship dynamics emerge and vary under within-population group-size heterogeneity, and how such locally dynamic, varying kinship environments may help to explain variation in age-linked trends in social traits, such as the timing of menopause in social mammals.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"475-482"},"PeriodicalIF":4.3,"publicationDate":"2026-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of behavioral flexibility and the forming and breaking of habits.","authors":"Olof Leimar, Sasha R X Dall, Peter Hammerstein, Alasdair I Houston, Bram Kuijper, John M McNamara","doi":"10.1093/evlett/qrag024","DOIUrl":"https://doi.org/10.1093/evlett/qrag024","url":null,"abstract":"<p><p>The formation of habits, whereby learnt actions come to be performed automatically with repetition and practice, is a well-established focus for studies in psychology. This contrasts with evolutionarily motivated studies of learning, which typically view behavior as either learnt or fixed, to elucidate the ecological conditions where each predominates. Here, we envisage habit formation functioning to free up limited mental resources (e.g., attention), potentially improving an individual's ability to multitask. As an ecologically relevant case, we investigate exploration-exploitation in foraging under predation risk. In our model, a forager does not know the quality of feeding options, but can learn from the rewards they give. When the environment occasionally changes, individuals can attend to exploration of feeding options in the new conditions. The options can then become habitually exploited, freeing attention for antipredatory vigilance. Via evolutionary simulations, we show that evolutionarily stable forming and breaking of foraging habits can substantially reduce mortality from predation, without drastically reducing foraging success, when environmental conditions remain stable enough between changes. We identify factors promoting habit formation, such as the repetition of actions that yield predictable rewards, and also discuss the role of habits more generally, including their relation to ideas about bounded rationality in theories of decision-making. In conclusion, we argue that exploration-exploitation strategies involving the forming and breaking of habits are a type of behavioral flexibility that is likely to be selected for under a range of ecological conditions.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 5","pages":"463-474"},"PeriodicalIF":4.3,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13629241/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coevolution of species' range borders: Interactions between interspecific competition, gene flow, and matching habitat choice.","authors":"Farshad Shirani, Judith R Miller, Benjamin G Freeman","doi":"10.1093/evlett/qrag022","DOIUrl":"10.1093/evlett/qrag022","url":null,"abstract":"<p><p>Existing theory examining the coevolutionary dynamics of species' range borders assumes random dispersal, which causes maladaptive gene flow from the range core to the range margins and contributes to the formation of range limits. However, dispersal is unlikely to be random for many organisms in nature, calling into question existing theoretical predictions. For example, if individuals exhibit phenotype-dependent adaptive dispersal strategies such as matching habitat choice, then the resulting adaptive gene flow toward species' range margins could facilitate range expansions and potentially prevent the formation of range limits by interspecific competition. To test this idea, we use a comprehensive mathematical model to develop a quantitative theory of range border coevolution that incorporates phenotype-optimal dispersal-a particular form of matching habitat choice in which individuals follow the gradient in an environmental optimum phenotype to settle in the habit best suited for their phenotype. We find that instead of preventing competitively formed range limits, adaptive dispersal leads to sharper range limits and reduced character displacement in sympatry. These differences are particularly remarkable when natural selection is weak, when individuals are specialized in their resource use, or when individuals are highly sensitive to environmental conditions. We show that matching habitat choice causes backward edge-to-core movements, which dynamically interact with the effects of interspecific competition to establish the range limits. Thus, the formation of range limits by interspecific competition is robust to assumptions about individual dispersal. Further, our results identify the competitive advantage of evolving matching habitat choice in steep environmental gradients, especially for slowly growing species in rapidly fluctuating climates.</p>","PeriodicalId":48629,"journal":{"name":"Evolution Letters","volume":"10 4","pages":"427-440"},"PeriodicalIF":4.3,"publicationDate":"2026-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13451777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148698078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}