The relative magnitude of additive genetic vs. residual variation for fitness traits is important in models for predicting the rate of evolution and population persistence in response to changes in the environment. In many annual plants, lifetime reproductive fitness is correlated with end-of-season plant biomass, which can vary significantly from plant to plant in the same population. We measured end-of-season plant biomasses and obtained single nucleotide polymorphism (SNP) genotypes of plants in a dense, natural population of the annual plant species Impatiens capensis with hierarchical size structure. These data were used to estimate the amount of heritable variation for position in the size hierarchy and for plant biomass. Additive genetic variance for a position in the size hierarchy and plant biomass were both significantly different from zero. These results are discussed in relationship to the theory for the heritability of fitness in natural populations and ecological factors that potentially influence heritable variation for fitness in this species.
{"title":"The heritability of fitness in a wild annual plant population with hierarchical size structure.","authors":"Daniel J Schoen, Doug Speed","doi":"10.1093/evolut/qpae112","DOIUrl":"10.1093/evolut/qpae112","url":null,"abstract":"<p><p>The relative magnitude of additive genetic vs. residual variation for fitness traits is important in models for predicting the rate of evolution and population persistence in response to changes in the environment. In many annual plants, lifetime reproductive fitness is correlated with end-of-season plant biomass, which can vary significantly from plant to plant in the same population. We measured end-of-season plant biomasses and obtained single nucleotide polymorphism (SNP) genotypes of plants in a dense, natural population of the annual plant species Impatiens capensis with hierarchical size structure. These data were used to estimate the amount of heritable variation for position in the size hierarchy and for plant biomass. Additive genetic variance for a position in the size hierarchy and plant biomass were both significantly different from zero. These results are discussed in relationship to the theory for the heritability of fitness in natural populations and ecological factors that potentially influence heritable variation for fitness in this species.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1739-1745"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141751464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The process of reproductive character displacement involves divergence and/or the narrowing of variance in traits involved in species recognition, driven by interactions between taxa. However, stabilizing sexual selection may favor stasis and species similarity in these same traits if signals are optimized for transmission through the prevailing environment. Further, sexual selection may promote increased variability within species to facilitate individual recognition. Here we ask how the conflicting selection pressures of species recognition and sexual selection are resolved in a genus of Himalayan birds that sing exceptionally similar songs. We experimentally show that small differences in two traits (note shape and peak frequency) are both necessary and sufficient for species recognition. Song frequency shows remarkable clinal variation along the Himalayan elevational gradient, being most divergent where species co-occur, the classic signature of reproductive character displacement. Note shape shows no such clinal variation but varies more between individuals of an allopatric species than it does among individuals within species that co-occur. We argue that the different note shapes experience similar transmission constraints, and differences produced through species interactions spread back through the entire species range. Our results imply that reproductive character displacement is likely to be common.
{"title":"Evolution of species recognition when ecology and sexual selection favor signal stasis.","authors":"Pratap Singh, Trevor D Price","doi":"10.1093/evolut/qpae099","DOIUrl":"10.1093/evolut/qpae099","url":null,"abstract":"<p><p>The process of reproductive character displacement involves divergence and/or the narrowing of variance in traits involved in species recognition, driven by interactions between taxa. However, stabilizing sexual selection may favor stasis and species similarity in these same traits if signals are optimized for transmission through the prevailing environment. Further, sexual selection may promote increased variability within species to facilitate individual recognition. Here we ask how the conflicting selection pressures of species recognition and sexual selection are resolved in a genus of Himalayan birds that sing exceptionally similar songs. We experimentally show that small differences in two traits (note shape and peak frequency) are both necessary and sufficient for species recognition. Song frequency shows remarkable clinal variation along the Himalayan elevational gradient, being most divergent where species co-occur, the classic signature of reproductive character displacement. Note shape shows no such clinal variation but varies more between individuals of an allopatric species than it does among individuals within species that co-occur. We argue that the different note shapes experience similar transmission constraints, and differences produced through species interactions spread back through the entire species range. Our results imply that reproductive character displacement is likely to be common.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1647-1660"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141445941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pablo Lavaniegos-Puebla, Verónica A Rincón-Rubio, Alejandro Gonzalez-Voyer
Extant birds stand out among vertebrates in the diversity of parental care types they present, spanning absence of care to uniparental care by either sex, biparental care, or even cooperative care. Despite years of research, key questions remain regarding parental care evolution in birds. Firstly, the parental care type in the most recent ancestor of extant birds is a matter of controversy, with proposed ancestral states including no care, uniparental male or female care, and biparental care. Another unsolved question is the direction, order, and frequency of transitions between parental care types. We address these key questions using a database of 5,438 bird species (~50% of extant diversity) and modern phylogenetic comparative methods controlling simultaneously for model and phylogenetic uncertainty as well as potential confounding effects of state-dependent diversification. Our results indicate that the most likely ancestral state for extant birds is male-only care, with a posterior probability of 0.8. Transition rates across parental care types were generally low and heterogeneous; loss of parental care virtually never occurs and transitions away from female-only or cooperative care most often lead to biparental care. Given the low transition rates, future research should analyze the factors favoring the maintenance of care types.
{"title":"Who cares? Elucidating parental care evolution in extant birds.","authors":"Pablo Lavaniegos-Puebla, Verónica A Rincón-Rubio, Alejandro Gonzalez-Voyer","doi":"10.1093/evolut/qpae105","DOIUrl":"10.1093/evolut/qpae105","url":null,"abstract":"<p><p>Extant birds stand out among vertebrates in the diversity of parental care types they present, spanning absence of care to uniparental care by either sex, biparental care, or even cooperative care. Despite years of research, key questions remain regarding parental care evolution in birds. Firstly, the parental care type in the most recent ancestor of extant birds is a matter of controversy, with proposed ancestral states including no care, uniparental male or female care, and biparental care. Another unsolved question is the direction, order, and frequency of transitions between parental care types. We address these key questions using a database of 5,438 bird species (~50% of extant diversity) and modern phylogenetic comparative methods controlling simultaneously for model and phylogenetic uncertainty as well as potential confounding effects of state-dependent diversification. Our results indicate that the most likely ancestral state for extant birds is male-only care, with a posterior probability of 0.8. Transition rates across parental care types were generally low and heterogeneous; loss of parental care virtually never occurs and transitions away from female-only or cooperative care most often lead to biparental care. Given the low transition rates, future research should analyze the factors favoring the maintenance of care types.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1699-1709"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141563134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Despite their prevalence, family-living and cooperative breeding in birds have received little examination as to how and why they vary across species. Investigating the evolution of these social systems, Bliard et al. (2024) found that the presence of avian predators is associated with birds' social systems, with increases in predator presence corresponding to multiple shifts from non-family-living to cooperative breeding. Phylogenetic comparative analyses indicate that factors outside the breeding season can be selected for family-living and cooperative breeding.
{"title":"Digest: Cooperative breeding strategies in birds are shaped by avian predator richness.","authors":"Marquette Mutchler","doi":"10.1093/evolut/qpae113","DOIUrl":"10.1093/evolut/qpae113","url":null,"abstract":"<p><p>Despite their prevalence, family-living and cooperative breeding in birds have received little examination as to how and why they vary across species. Investigating the evolution of these social systems, Bliard et al. (2024) found that the presence of avian predators is associated with birds' social systems, with increases in predator presence corresponding to multiple shifts from non-family-living to cooperative breeding. Phylogenetic comparative analyses indicate that factors outside the breeding season can be selected for family-living and cooperative breeding.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1746-1747"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141859372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Social interactions are ubiquitous in nature and can shape the fitness of individuals through social selection. This type of selection arises when phenotypes of neighbors influence the fitness of a focal individual. Quantifying social selection is crucial to better characterize the overall selective landscape. For example, if intraspecific competition is strong, traits that are beneficial for an individual could be detrimental to competitors. In this study, we quantified social selection acting on three key ecological traits (body mass, wing length, and laying date) in wild Tree swallow (Tachycineta bicolor) females. We used reproductive success measured at three stages throughout the breeding season as fitness proxies to assess selection acting at those decisive moments. We also quantified the effects of environment on selection using measures of conspecifics' density, type of agricultural landscape, and presence of interspecific competitors. Overall, we found no strong evidence of social selection on these traits in our study system, although there were marginally nonsignificant selection gradients suggesting the positive effect of larger neighbors. Environmental variables affected reproductive success but did not strongly affect social selection gradients. Our study calls for more social selection estimates to be reported across environments to better understand its importance in wild populations.
{"title":"Social selection analysis reveals limited effect of neighbors' traits in Tree swallows.","authors":"Marie-Ève Labonté-Dupras, Carolyne Houle, Fanie Pelletier, Dany Garant","doi":"10.1093/evolut/qpae107","DOIUrl":"10.1093/evolut/qpae107","url":null,"abstract":"<p><p>Social interactions are ubiquitous in nature and can shape the fitness of individuals through social selection. This type of selection arises when phenotypes of neighbors influence the fitness of a focal individual. Quantifying social selection is crucial to better characterize the overall selective landscape. For example, if intraspecific competition is strong, traits that are beneficial for an individual could be detrimental to competitors. In this study, we quantified social selection acting on three key ecological traits (body mass, wing length, and laying date) in wild Tree swallow (Tachycineta bicolor) females. We used reproductive success measured at three stages throughout the breeding season as fitness proxies to assess selection acting at those decisive moments. We also quantified the effects of environment on selection using measures of conspecifics' density, type of agricultural landscape, and presence of interspecific competitors. Overall, we found no strong evidence of social selection on these traits in our study system, although there were marginally nonsignificant selection gradients suggesting the positive effect of larger neighbors. Environmental variables affected reproductive success but did not strongly affect social selection gradients. Our study calls for more social selection estimates to be reported across environments to better understand its importance in wild populations.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1710-1721"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141579356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bonita M Mendel, Angelique K Asselin, Karyn N Johnson, Katrina McGuigan
The impact of selection on host immune function genes has been widely documented. However, it remains essentially unknown how mutation influences the quantitative immune traits that selection acts on. Applying a classical mutation accumulation (MA) experimental design in Drosophila serrata, we found the mutational variation in susceptibility (median time of death, LT50) to Drosophila C virus (DCV) was of similar magnitude to that reported for intrinsic survival traits. Mean LT50 did not change as mutations accumulated, suggesting no directional bias in mutational effects. Maintenance of genetic variance in immune function is hypothesized to be influenced by pleiotropic effects on immunity and other traits that contribute to fitness. To investigate this, we assayed female reproductive output for a subset of MA lines with relatively long or short survival times under DCV infection. Longer survival time tended to be associated with lower reproductive output, suggesting that mutations affecting susceptibility to DCV had pleiotropic effects on investment in reproductive fitness. Further studies are needed to uncover the general patterns of mutational effect on immune responses and other fitness traits, and to determine how selection might typically act on new mutations via their direct and pleiotropic effects.
选择对宿主免疫功能基因的影响已被广泛记录。然而,变异如何影响选择所作用的定量免疫特征,这一点基本上还是未知数。通过在血清果蝇中应用经典的突变累积(MA)实验设计,我们发现C型果蝇病毒(DCV)易感性(中位死亡时间,LT50)的突变变异程度与报道的内在生存性状的突变变异程度相似。LT50的平均值不会随着突变的累积而改变,这表明突变效应不存在方向性偏差。据推测,免疫功能遗传变异的维持会受到对免疫和其他有助于提高适应性的性状的多效应的影响。为了研究这一点,我们对在 DCV 感染下存活时间相对较长或较短的 MA 品系进行了雌性繁殖力测定。较长的存活时间往往与较低的生殖产量有关,这表明影响对DCV易感性的突变对生殖适应性投资具有多向效应。还需要进一步的研究来揭示突变对免疫反应和其他体能性状影响的一般模式,并确定选择通常如何通过其直接效应和多效应作用于新的突变。
{"title":"Effects of spontaneous mutations on survival and reproduction of Drosophila serrata infected with Drosophila C virus.","authors":"Bonita M Mendel, Angelique K Asselin, Karyn N Johnson, Katrina McGuigan","doi":"10.1093/evolut/qpae101","DOIUrl":"10.1093/evolut/qpae101","url":null,"abstract":"<p><p>The impact of selection on host immune function genes has been widely documented. However, it remains essentially unknown how mutation influences the quantitative immune traits that selection acts on. Applying a classical mutation accumulation (MA) experimental design in Drosophila serrata, we found the mutational variation in susceptibility (median time of death, LT50) to Drosophila C virus (DCV) was of similar magnitude to that reported for intrinsic survival traits. Mean LT50 did not change as mutations accumulated, suggesting no directional bias in mutational effects. Maintenance of genetic variance in immune function is hypothesized to be influenced by pleiotropic effects on immunity and other traits that contribute to fitness. To investigate this, we assayed female reproductive output for a subset of MA lines with relatively long or short survival times under DCV infection. Longer survival time tended to be associated with lower reproductive output, suggesting that mutations affecting susceptibility to DCV had pleiotropic effects on investment in reproductive fitness. Further studies are needed to uncover the general patterns of mutational effect on immune responses and other fitness traits, and to determine how selection might typically act on new mutations via their direct and pleiotropic effects.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":"1661-1672"},"PeriodicalIF":3.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141456107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many influential mathematical models of sexual selection have stressed that mating preferences evolve due to correlations that build between mating preferences and preferred display traits - that is, through indirect selection. Nevertheless, there is a perception that indirect selection should generally be overwhelmed by direct selection, for example in the form of search costs. Recent work by Fry has used quantitative genetic models to argue that in many cases, including when there are direct benefits (a fecundity advantage to mating with the preferred male), direct and indirect selection may be of similar magnitude. Here I use population genetic models, in which the strength of the genetic correlation is an emergent property of evolution at mating preference and display trait loci, to assess the relative contributions of direct and indirect selection to the evolution of mating preferences. For the cases of direct benefits and of indirect benefits with fixed and frequency-dependent search costs, I outline parameter values of fecundity benefits, preference strengths, and search costs for which indirect selection on female preferences can potentially predominate. I also analyze male mate choice under polygyny, showing that direct selection will always outweigh indirect selection except when there are direct benefits.
{"title":"The contributions of direct and indirect selection to the evolution of mating preferences.","authors":"Maria R Servedio","doi":"10.1093/evolut/qpae139","DOIUrl":"https://doi.org/10.1093/evolut/qpae139","url":null,"abstract":"<p><p>Many influential mathematical models of sexual selection have stressed that mating preferences evolve due to correlations that build between mating preferences and preferred display traits - that is, through indirect selection. Nevertheless, there is a perception that indirect selection should generally be overwhelmed by direct selection, for example in the form of search costs. Recent work by Fry has used quantitative genetic models to argue that in many cases, including when there are direct benefits (a fecundity advantage to mating with the preferred male), direct and indirect selection may be of similar magnitude. Here I use population genetic models, in which the strength of the genetic correlation is an emergent property of evolution at mating preference and display trait loci, to assess the relative contributions of direct and indirect selection to the evolution of mating preferences. For the cases of direct benefits and of indirect benefits with fixed and frequency-dependent search costs, I outline parameter values of fecundity benefits, preference strengths, and search costs for which indirect selection on female preferences can potentially predominate. I also analyze male mate choice under polygyny, showing that direct selection will always outweigh indirect selection except when there are direct benefits.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142344232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R Axel W Wiberg, Rosalind L Murray, Elizabeth Herridge, Varpu Pärssinen, Darryl T Gwynne, Luc F Bussière
The prevalence and diversity of female ornaments poses a challenge to evolutionary theory because males should prefer mates that spend resources on offspring rather than ornaments. Among dance flies, there is extraordinary variation in sexual dimorphism. Females of many species have conspicuous ornaments (leg scales and inflatable abdominal sacs). Meanwhile males of some species have exaggerated regions of their eyes with larger ommatidial facets that allow for regionally elevated photosensitivity and/or acuity. Here, we conduct a comparative study of these traits using both species descriptions available from the literature, as well as quantitative measures of eyes and ornaments from wild-caught flies. We show a conspicuous covariance across species between exaggerated male dorsal eye regions and the extent of female ornaments: species with highly ornamented females have males with more exaggerated eyes. We discuss this pattern in the context of competing hypotheses for the evolution of these traits and propose a plausible role for sexually antagonistic coevolution.
{"title":"Sexually antagonistic co-evolution can explain female display signals and male sensory adaptations.","authors":"R Axel W Wiberg, Rosalind L Murray, Elizabeth Herridge, Varpu Pärssinen, Darryl T Gwynne, Luc F Bussière","doi":"10.1093/evolut/qpae133","DOIUrl":"https://doi.org/10.1093/evolut/qpae133","url":null,"abstract":"<p><p>The prevalence and diversity of female ornaments poses a challenge to evolutionary theory because males should prefer mates that spend resources on offspring rather than ornaments. Among dance flies, there is extraordinary variation in sexual dimorphism. Females of many species have conspicuous ornaments (leg scales and inflatable abdominal sacs). Meanwhile males of some species have exaggerated regions of their eyes with larger ommatidial facets that allow for regionally elevated photosensitivity and/or acuity. Here, we conduct a comparative study of these traits using both species descriptions available from the literature, as well as quantitative measures of eyes and ornaments from wild-caught flies. We show a conspicuous covariance across species between exaggerated male dorsal eye regions and the extent of female ornaments: species with highly ornamented females have males with more exaggerated eyes. We discuss this pattern in the context of competing hypotheses for the evolution of these traits and propose a plausible role for sexually antagonistic coevolution.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142344231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brain size variation is often attributed to energetic trade-offs with other metabolically expensive tissues and organs, which is a prediction of the expensive brain hypothesis (EBH). Here we examine Asiatic toads (Bufo gargarizans) along altitudinal gradients, and test size trade-offs between brain and four visceral organs (heart, liver, alimentary tract, and kidney) with altitude. Body size and scaled mass index (SMI; a proxy for total energy intake) decline with altitude, implying stronger energetic constraints at high altitudes. Relative brain size decreases along altitudinal gradients while visceral organs mostly increase in relative sizes. Using structural equation modelling, a significant negative relationship between brain size and a latent variable 'budget', which represents the energy allocation to the four visceral organs, is detected among high-altitudinal toads. Heart appears to have the largest and most consistent response to changes of energy allocation. No such relationships are observed among toads at middle and low altitudes, where high energy intake may allow individuals to forego energetic trade-offs. When applying EBH to poikilotherms, a great emphasis should be placed on total energy intake in addition to energy allocation. Future research on EBH will benefit from more intra-specific comparisons and the evaluation of fitness consequences beyond energy limitation.
{"title":"Does brain size of Asiatic toads (Bufo gargarizans) trade-off with other energetically expensive organs along altitudinal gradients?","authors":"Zhongyi Yao, Kun Huang, Yin Qi, Jinzhong Fu","doi":"10.1093/evolut/qpae137","DOIUrl":"https://doi.org/10.1093/evolut/qpae137","url":null,"abstract":"<p><p>Brain size variation is often attributed to energetic trade-offs with other metabolically expensive tissues and organs, which is a prediction of the expensive brain hypothesis (EBH). Here we examine Asiatic toads (Bufo gargarizans) along altitudinal gradients, and test size trade-offs between brain and four visceral organs (heart, liver, alimentary tract, and kidney) with altitude. Body size and scaled mass index (SMI; a proxy for total energy intake) decline with altitude, implying stronger energetic constraints at high altitudes. Relative brain size decreases along altitudinal gradients while visceral organs mostly increase in relative sizes. Using structural equation modelling, a significant negative relationship between brain size and a latent variable 'budget', which represents the energy allocation to the four visceral organs, is detected among high-altitudinal toads. Heart appears to have the largest and most consistent response to changes of energy allocation. No such relationships are observed among toads at middle and low altitudes, where high energy intake may allow individuals to forego energetic trade-offs. When applying EBH to poikilotherms, a great emphasis should be placed on total energy intake in addition to energy allocation. Future research on EBH will benefit from more intra-specific comparisons and the evaluation of fitness consequences beyond energy limitation.</p>","PeriodicalId":12082,"journal":{"name":"Evolution","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142282505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Socially induced plasticity in reproductive effort is a widely documented phenomenon. However, few empirical studies have examined how male and female plastic responses to the social environment might interact in determining fitness outcomes. In field crickets, Teleogryllus oceanicus, males respond to rival song by increasing expenditure on seminal fluid proteins that enhance competitive fertilization success at the cost of reduced embryo survival. It remains unknown whether plastic responses in females could moderate the effects of male competitiveness on offspring performance. Here we used a fully factorial design to explore the interacting effects on fitness of male and female plasticity to the sociosexual environment. We found that female crickets exposed to male song increased the number of eggs produced during early life reproduction, which came at a cost of reduced offspring size. There was evidence, albeit weak, that interacting effects of male and female sociosexual environment contributed to variation in the hatching success of eggs laid by females. Lifetime offspring production was unaffected by the sociosexual environments to which upstream male and female plastic responses were made. Our data offer a rare test of the theoretical expectation that male and female plasticities should interact in their effects on female fitness.
{"title":"Interacting phenotypic plasticities: Do male and female responses to the sociosexual environment interact to determine fitness?","authors":"Leigh W Simmons,Maxine Lovegrove","doi":"10.1093/evolut/qpae122","DOIUrl":"https://doi.org/10.1093/evolut/qpae122","url":null,"abstract":"Socially induced plasticity in reproductive effort is a widely documented phenomenon. However, few empirical studies have examined how male and female plastic responses to the social environment might interact in determining fitness outcomes. In field crickets, Teleogryllus oceanicus, males respond to rival song by increasing expenditure on seminal fluid proteins that enhance competitive fertilization success at the cost of reduced embryo survival. It remains unknown whether plastic responses in females could moderate the effects of male competitiveness on offspring performance. Here we used a fully factorial design to explore the interacting effects on fitness of male and female plasticity to the sociosexual environment. We found that female crickets exposed to male song increased the number of eggs produced during early life reproduction, which came at a cost of reduced offspring size. There was evidence, albeit weak, that interacting effects of male and female sociosexual environment contributed to variation in the hatching success of eggs laid by females. Lifetime offspring production was unaffected by the sociosexual environments to which upstream male and female plastic responses were made. Our data offer a rare test of the theoretical expectation that male and female plasticities should interact in their effects on female fitness.","PeriodicalId":12082,"journal":{"name":"Evolution","volume":"19 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}