The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents...The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents the biogeographic and evolutionary history of species should incorporate with current environments.We aim to address two following questions:1)How does plant taxonomic and phylogenetic diversity with disparate biogeographic affinitiesvary along the subtropical elevational gradient?2)How do biogeographic affinityand environmental drivers regulate the community assembly?We collected woody plant survey data of 32 forest plots in a subtropical mountain of Mt.Guanshan with typical transitional characteristics,including 250 woody plant species belonging to 56 families and 118 genera.We estimated the effects of biogeographic affinity,climate and soil properties on taxonomic and phylogenetic diversity of plant communities employing linear regression and structural equation models.We found that the richness of temperate-affiliated species increased with elevations,but the evenness decreased,while tropical-affiliatedspecies had no significantpatterns.Winter temperature directly or indirectly via biogeographic affinityshaped the assemblage of woody plant communities along elevations.Biogeographic affinityaffected what kind of species could colonize higher elevations while local environment determined their fitnessto adapt.These results suggest that biogeographic affinityand local environment jointly lead to the dominance of temperate-affiliated species at higher elevations and shape the diversity of woody plant communities along elevational gradients.Our findingshighlight the legacy effect of biogeographic affinityon the composition and structure of subtropical montane forests.展开更多
Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related...Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related species tend to share similar niches,although this relationship may be influenced by various ecological and evolutionary factors.To test this,we classified alien Asteraceae species in China into three categories based on their invasion status and the extent of ecological damage:introduced,naturalized,and invasive.We then compared the genetic relationships and niche overlap between alien and native Asteraceae species.We found that invasive Asteraceae species are more closely related to native Asteraceae species than are introduced and naturalized species.However,alien Asteraceae species(including introduced,naturalized,and invasive species)exhibited relatively low niche overlap with native Asteraceae species.These findings suggest that the main premise underlying Darwin’s naturalization conundrum,namely,the universality of phylogenetic niche conservatism,may not hold true.Instead,our findings indicate that alien species are more likely to invade successfully when they are more closely related to native plants,exhibit less niche overlap,and maintain conservative niches during the invasion process.These findings provide new insights into the mechanisms of alien plant invasions,highlight the relationship between alien species invasions and native community vulnerability,and offer important insights into the development of effective biological invasion management strategies.展开更多
In the last few years,scholars have continued to refine the understanding of conservatism through cultural psychology.The application of Symbolic Action Theory,particularly Ernst Boesch’s framework,remains central to...In the last few years,scholars have continued to refine the understanding of conservatism through cultural psychology.The application of Symbolic Action Theory,particularly Ernst Boesch’s framework,remains central to discussions,illustrating how conservatism is not merely a political stance but a dynamic system of behaviors that reinforces societal values through symbolic actions(Kölbl,2020).Additionally,recent studies have highlighted the interaction between cultural conservatism and collective identity,with particular focus on how conservatism can manifest in diverse cultural settings(Yilmaz&Alper,2019).Research also underscores the relevance of symbolic politics in shaping both individual attitudes and broader political actions,contributing to the understanding of how symbolic meanings sustain social conservatism in different cultural contexts(Chin&Levey,2022).展开更多
Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in the...Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in these displays may have interesting effects, such as eliciting innate avoidance against novel colored prey, or improving learning and memory of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick's innate avoidance behavior, and the learning and memory of prey avoidance. The results demonstrate that the buzzing sound had no effect on the predator's responses to unpalatable aposematically colored crumbs, suggesting that the agitated buzzing of B. terrestris may provide no additional protection from avian predators .展开更多
Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a ...Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a discussion of their evolution.Four phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and evaluated.They enabled/facilitated the evolutionary process.Although, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach(i.e., descriptive, diagnosis, testing/evaluation and finally dissemination), much still needs to be done.This leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable manner.Given the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers' intimate involvement in their identification, evaluation and dissemination.Discussion in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders(i.e., farmers, scientists, extension workers, input/output service providers and policymakers).Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research(i.e., CGIAR) system.The paper concludes with a short discussion on the potential role of formal modelling.展开更多
Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distrib...Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China.展开更多
Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal ...Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal diversity gradient.However,few studies have tested which of the two climate variables is the primary determinant.In this study,we assess whether winter coldness or temperature seasonality is more strongly associated with the northern latitudinal limits of tree species and with tree species richness in North America.Tree species were recorded in each of 1198 quadrats of 110 km×110 km in North America.We used correlation and regression analyses to assess the relationship of the latitude of the northern boundary of each species,and of species richness per quadrat,with winter coldness and temperature seasonality.Species richness was analyzed within 38 longitudinal,i.e.,north-south,bands(each being>1100 km long and 110 km wide).The latitudes of the northern range limits of tree species were three times better correlated with minimum temperatures at those latitudes than with temperature seasonality.On average,minimum temperature and temperature seasonality together explained 81.5%of the variation in the northern range limits of the tree species examined,and minimum temperature uniquely explained six-fold(33.7%versus 5.8%)more of this variation than did temperature seasonality.Correlations of tree species richness with minimum temperatures were stronger than correlations with temperature seasonality for most of the longitudinal bands analyzed.Compared to temperature seasonality,winter coldness is more strongly associated with species distributions at high latitudes,and is likely a more important driver of the latitudinal diversity gradient.展开更多
In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the...In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the traditional splitting methods but also can the physical feature of mutual dependence of the fast and the slow stages that are calculated separately and splittingly be kept as well. Moreover, the method owns an universality, it can be generalized to other square-conservative difference schemes, such as the implicit and complete ones and the explicit and instantaneous ones. Good time benefits can be acquired when it is applied in the numerical simulations of the monthly mean currents of the South China Sea.展开更多
Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation ...Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human activities.Using a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in Brazil.We recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil characterization.We fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary distinctiveness.We found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water availability.The inferior inselberg habitats harbor higher lineage diversity than expected by chance.Soil strongly predicted evolutionary diversity.We concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.展开更多
Phylogenetic niche conservatism posits that species tend to retain ancestral ecological traits and distributions,which has been broadly tested for lineages originating in tropical climates but has been rarely tested f...Phylogenetic niche conservatism posits that species tend to retain ancestral ecological traits and distributions,which has been broadly tested for lineages originating in tropical climates but has been rarely tested for lineages that originated and diversified in temperate climates.Liverworts are thought to originate in temperate climates.Mean lineage age reflects evolutionary history of biological communities.Here,using regional liverwort floras across a long latitudinal gradient from tropical to arctic climates in North America,we test the age-component of the temperate niche conservatism hypothesis.Mean genus age(MGA)was estimated for each of 76 regional floras of liverworts.We related MGA to climatic variables for North America as a whole and for its eastern and western parts separately,and used variation partitioning analysis to assess the relative importance of temperature-versus precipitationrelated variables and of climate extremes versus seasonality on MGA.We found that older genera of liverworts tend to concentrate in humid regions of intermediate temperatures in the range of 10℃-20℃,from which liverworts have adapted to and diversified into more arid,colder,and hotter regions,supporting the temperate niche conservatism hypothesis.We also found that across North America the MGA of liverwort assemblages is more strongly affected by precipitation-related variables than by temperature-related variables,and is more strongly affected by climate extremes than by climate seasonality.Geographic patterns of the MGA of liverworts are consistent with the temperate niche conservatism hypothesis,rather than the tropical niche conservatism hypothesis,the latter of which is broadly supported by angiosperms.展开更多
基金financialsupport from the Jiangxi Natural Science Foundation(20242BAB25345)to Z.Z.the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD36)to J.Z.
文摘The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents the biogeographic and evolutionary history of species should incorporate with current environments.We aim to address two following questions:1)How does plant taxonomic and phylogenetic diversity with disparate biogeographic affinitiesvary along the subtropical elevational gradient?2)How do biogeographic affinityand environmental drivers regulate the community assembly?We collected woody plant survey data of 32 forest plots in a subtropical mountain of Mt.Guanshan with typical transitional characteristics,including 250 woody plant species belonging to 56 families and 118 genera.We estimated the effects of biogeographic affinity,climate and soil properties on taxonomic and phylogenetic diversity of plant communities employing linear regression and structural equation models.We found that the richness of temperate-affiliated species increased with elevations,but the evenness decreased,while tropical-affiliatedspecies had no significantpatterns.Winter temperature directly or indirectly via biogeographic affinityshaped the assemblage of woody plant communities along elevations.Biogeographic affinityaffected what kind of species could colonize higher elevations while local environment determined their fitnessto adapt.These results suggest that biogeographic affinityand local environment jointly lead to the dominance of temperate-affiliated species at higher elevations and shape the diversity of woody plant communities along elevational gradients.Our findingshighlight the legacy effect of biogeographic affinityon the composition and structure of subtropical montane forests.
基金supported by the National Natural Science Foundation of China(32271584 and 31600445)the Natural Science Basic Research Plan in Shaanxi Province of China(2020JM-286)+2 种基金the Fundamental Research Funds for the Central Universities(GK202103072 and GK202103073)the Key Research and Development Program of Shaanxi Province(2025SF-YBXM-514)Special Research Project in Philosophy and Social Sciences of Shaanxi Province(2022HZ1795).
文摘Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related species tend to share similar niches,although this relationship may be influenced by various ecological and evolutionary factors.To test this,we classified alien Asteraceae species in China into three categories based on their invasion status and the extent of ecological damage:introduced,naturalized,and invasive.We then compared the genetic relationships and niche overlap between alien and native Asteraceae species.We found that invasive Asteraceae species are more closely related to native Asteraceae species than are introduced and naturalized species.However,alien Asteraceae species(including introduced,naturalized,and invasive species)exhibited relatively low niche overlap with native Asteraceae species.These findings suggest that the main premise underlying Darwin’s naturalization conundrum,namely,the universality of phylogenetic niche conservatism,may not hold true.Instead,our findings indicate that alien species are more likely to invade successfully when they are more closely related to native plants,exhibit less niche overlap,and maintain conservative niches during the invasion process.These findings provide new insights into the mechanisms of alien plant invasions,highlight the relationship between alien species invasions and native community vulnerability,and offer important insights into the development of effective biological invasion management strategies.
基金supported by the Philosophy and Social Science Research Fund of Zhejiang Province(Grant No.24ZJQN095YB)the Educational and Teaching Reform Project of HDU-ITMO Joint Institute(Grant No.SGJ2023JG007).
文摘In the last few years,scholars have continued to refine the understanding of conservatism through cultural psychology.The application of Symbolic Action Theory,particularly Ernst Boesch’s framework,remains central to discussions,illustrating how conservatism is not merely a political stance but a dynamic system of behaviors that reinforces societal values through symbolic actions(Kölbl,2020).Additionally,recent studies have highlighted the interaction between cultural conservatism and collective identity,with particular focus on how conservatism can manifest in diverse cultural settings(Yilmaz&Alper,2019).Research also underscores the relevance of symbolic politics in shaping both individual attitudes and broader political actions,contributing to the understanding of how symbolic meanings sustain social conservatism in different cultural contexts(Chin&Levey,2022).
文摘Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in these displays may have interesting effects, such as eliciting innate avoidance against novel colored prey, or improving learning and memory of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick's innate avoidance behavior, and the learning and memory of prey avoidance. The results demonstrate that the buzzing sound had no effect on the predator's responses to unpalatable aposematically colored crumbs, suggesting that the agitated buzzing of B. terrestris may provide no additional protection from avian predators .
文摘Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a discussion of their evolution.Four phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and evaluated.They enabled/facilitated the evolutionary process.Although, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach(i.e., descriptive, diagnosis, testing/evaluation and finally dissemination), much still needs to be done.This leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable manner.Given the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers' intimate involvement in their identification, evaluation and dissemination.Discussion in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders(i.e., farmers, scientists, extension workers, input/output service providers and policymakers).Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research(i.e., CGIAR) system.The paper concludes with a short discussion on the potential role of formal modelling.
基金funded by the Three New Forestry Project of Jiangsuthe Forestry Technological Innovation and Promotion Program of Jiangsu Province+1 种基金the Postgraduate Research and Practice Innovation Program of Jiangsu Provincethe Doctorate Fellowship Foundation of Nanjing Forestry University,grant number,LYSX[2015]17,LYKJ[2018]29 and KYCX17-0815,respectively。
文摘Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China.
基金supported by a grant form the National Key Research and Development Program,No.2019YFA0607302。
文摘Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal diversity gradient.However,few studies have tested which of the two climate variables is the primary determinant.In this study,we assess whether winter coldness or temperature seasonality is more strongly associated with the northern latitudinal limits of tree species and with tree species richness in North America.Tree species were recorded in each of 1198 quadrats of 110 km×110 km in North America.We used correlation and regression analyses to assess the relationship of the latitude of the northern boundary of each species,and of species richness per quadrat,with winter coldness and temperature seasonality.Species richness was analyzed within 38 longitudinal,i.e.,north-south,bands(each being>1100 km long and 110 km wide).The latitudes of the northern range limits of tree species were three times better correlated with minimum temperatures at those latitudes than with temperature seasonality.On average,minimum temperature and temperature seasonality together explained 81.5%of the variation in the northern range limits of the tree species examined,and minimum temperature uniquely explained six-fold(33.7%versus 5.8%)more of this variation than did temperature seasonality.Correlations of tree species richness with minimum temperatures were stronger than correlations with temperature seasonality for most of the longitudinal bands analyzed.Compared to temperature seasonality,winter coldness is more strongly associated with species distributions at high latitudes,and is likely a more important driver of the latitudinal diversity gradient.
基金Partly supported by the State Major Key Project for Basic Researches
文摘In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the traditional splitting methods but also can the physical feature of mutual dependence of the fast and the slow stages that are calculated separately and splittingly be kept as well. Moreover, the method owns an universality, it can be generalized to other square-conservative difference schemes, such as the implicit and complete ones and the explicit and instantaneous ones. Good time benefits can be acquired when it is applied in the numerical simulations of the monthly mean currents of the South China Sea.
基金Coordination for the Improvement of Higher Education Personnel(CAPES)the National Council for Scientific and Technological Development(CNPq)the Minas Gerais State Research Foundation(FAPEMIG)for research funding and scholarships to the authors。
文摘Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human activities.Using a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in Brazil.We recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil characterization.We fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary distinctiveness.We found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water availability.The inferior inselberg habitats harbor higher lineage diversity than expected by chance.Soil strongly predicted evolutionary diversity.We concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.
文摘Phylogenetic niche conservatism posits that species tend to retain ancestral ecological traits and distributions,which has been broadly tested for lineages originating in tropical climates but has been rarely tested for lineages that originated and diversified in temperate climates.Liverworts are thought to originate in temperate climates.Mean lineage age reflects evolutionary history of biological communities.Here,using regional liverwort floras across a long latitudinal gradient from tropical to arctic climates in North America,we test the age-component of the temperate niche conservatism hypothesis.Mean genus age(MGA)was estimated for each of 76 regional floras of liverworts.We related MGA to climatic variables for North America as a whole and for its eastern and western parts separately,and used variation partitioning analysis to assess the relative importance of temperature-versus precipitationrelated variables and of climate extremes versus seasonality on MGA.We found that older genera of liverworts tend to concentrate in humid regions of intermediate temperatures in the range of 10℃-20℃,from which liverworts have adapted to and diversified into more arid,colder,and hotter regions,supporting the temperate niche conservatism hypothesis.We also found that across North America the MGA of liverwort assemblages is more strongly affected by precipitation-related variables than by temperature-related variables,and is more strongly affected by climate extremes than by climate seasonality.Geographic patterns of the MGA of liverworts are consistent with the temperate niche conservatism hypothesis,rather than the tropical niche conservatism hypothesis,the latter of which is broadly supported by angiosperms.