[Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chine...[Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chinensis populations in Zhalong National Nature Reserve.[Method] Four phenotypic traits of five Leymus chinensis populations in Zhalong Wetlands were comparison and analysis using principal component analysis method and UPGMA cluster analysis method.[Result] There were significant differences among the four phenotypic traits of five populations,the order of coefficients of variation were node number〉plant height〉leaf width〉leaf length;the order of variation degrees of the populations from large to small was KQH,MD,JZ,ZK,TTG population.Results of principal component analysis suggested that the four traits were all factors led to the phenotypic differences among the populations of Leymus chinensis.Leymus chinensis of five populations were divided into three groups by cluster analysis,MD,JZ and TTG were classified as one group,KQH and ZK population were individually classified as one group.[Conclusion] Leymus chinensis had large-scale phenotypic variations and showed strong adaptability to different habitats,which was very important for selection,breeding of fine varieties and germplasm conservation.展开更多
While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social ...While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.展开更多
Aims Plant populations in managed grasslands are subject to strong selection exerted by grazing,mowing and fertilization.Many previous studies showed that this can cause evolutionary changes in mean trait values,but l...Aims Plant populations in managed grasslands are subject to strong selection exerted by grazing,mowing and fertilization.Many previous studies showed that this can cause evolutionary changes in mean trait values,but little is known about the evolution of phenotypic plasticity in response to land use.In this study,we aimed to elucidate the relationships between phenotypic plasticity—specifically,regrowth ability after biomass removal—and the intensity of grassland management and levels of temporal variation therein.Methods We conducted an outdoor common garden experiment to test if plants from more intensively mown and grazed sites showed an increased ability to regrow after biomass removal.We used three common plant species from temperate European grasslands,with seed material from 58 to 68 populations along gradients of land-use intensity,ranging from extensive(only light grazing)to very intensive management(up to four cuts per year).Important Findings In two out of three species,we found significant population differentiation in regrowth ability after clipping.While variation in regrowth ability was unrelated to the mean land-use intensity of populations of origin,we found a relationship with its temporal variation in Plantago lanceolata,where plants experiencing less variable environmental conditions over the last 11 years showed stronger regrowth in reproductive biomass after clipping.Therefore,while mean grazing and mowing intensity may not select for regrowth ability,the temporal stability of the environmental heterogeneity created by land use may have caused its evolution in some species.展开更多
Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and...Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of ＂inducible competitors＂. Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity展开更多
Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized p...Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized patterns that emerge from the interactions of individual modules. Interactions include both competition and cooperation,and several types of positive and negative feedback loops are involved. Development can be open to external influences, thus enabling the plant to adjust its form to the environment,for example, to the spatial distribution of ecological resources. This paper provides a review on adaptive plasticity in plants.展开更多
基金Supported by National Natural Science Foundation of China(40971053)~~
文摘[Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chinensis populations in Zhalong National Nature Reserve.[Method] Four phenotypic traits of five Leymus chinensis populations in Zhalong Wetlands were comparison and analysis using principal component analysis method and UPGMA cluster analysis method.[Result] There were significant differences among the four phenotypic traits of five populations,the order of coefficients of variation were node number〉plant height〉leaf width〉leaf length;the order of variation degrees of the populations from large to small was KQH,MD,JZ,ZK,TTG population.Results of principal component analysis suggested that the four traits were all factors led to the phenotypic differences among the populations of Leymus chinensis.Leymus chinensis of five populations were divided into three groups by cluster analysis,MD,JZ and TTG were classified as one group,KQH and ZK population were individually classified as one group.[Conclusion] Leymus chinensis had large-scale phenotypic variations and showed strong adaptability to different habitats,which was very important for selection,breeding of fine varieties and germplasm conservation.
基金Acknowledgement We sincerely appreciate the commendable field efforts of a large number of field technicians who assisted with data collection during the course of this study, as well as logistical support provided by B. Congdon, T. Daniel, J. Lindsay and D. Westcott. We also thank members of the Schwabl and Webster labs for their valuable input throughout. Thanks also to Becca Sail＇an and Maren Vitousek for the invitation to contribute to this volume. This research was conducted with appropriate permits and permissions from the governments of Queensland and Australia, and material is based upon work supported by the National Science Foundation （USA） through grants to MSW and HS and a graduate traineeship to DGB.
文摘While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.
基金The work was supported by the Deutsche Forschungsgemeinschaft Priority Program 1374'Infrastructure-Biodiversity-Exploratories’through project SCHE 1899/1-1 to J.F.S.
文摘Aims Plant populations in managed grasslands are subject to strong selection exerted by grazing,mowing and fertilization.Many previous studies showed that this can cause evolutionary changes in mean trait values,but little is known about the evolution of phenotypic plasticity in response to land use.In this study,we aimed to elucidate the relationships between phenotypic plasticity—specifically,regrowth ability after biomass removal—and the intensity of grassland management and levels of temporal variation therein.Methods We conducted an outdoor common garden experiment to test if plants from more intensively mown and grazed sites showed an increased ability to regrow after biomass removal.We used three common plant species from temperate European grasslands,with seed material from 58 to 68 populations along gradients of land-use intensity,ranging from extensive(only light grazing)to very intensive management(up to four cuts per year).Important Findings In two out of three species,we found significant population differentiation in regrowth ability after clipping.While variation in regrowth ability was unrelated to the mean land-use intensity of populations of origin,we found a relationship with its temporal variation in Plantago lanceolata,where plants experiencing less variable environmental conditions over the last 11 years showed stronger regrowth in reproductive biomass after clipping.Therefore,while mean grazing and mowing intensity may not select for regrowth ability,the temporal stability of the environmental heterogeneity created by land use may have caused its evolution in some species.
基金Acknowledgements We thank Zhi-Yun Jia for inviting us to submit this paper to a special column on phenotypic plasticity. Three anonymous reviewers provided valuable commentary that encouraged us to improve this work. We also wish to ac- knowledge the long term funding for plasticity research pro- vided by the U.S. National Science Foundation to DP, and the Natural Sciences and Engineering Research Council of Can- ada to BR. Finally, collaboration on this specific project was directly supported through a short-term fellowship to BR by the National Evolutionary Synthesis Center （NESCent funded by NSF #EF-0905606）.
文摘Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of ＂inducible competitors＂. Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity
基金This research was subsidized by the Hungarian National Research Fund(OTKA T35009,and NWOOTKA N34028),the Hungarian Ministry of Education(FKFP 0187/1990,Istvn Szchenyi Scolarship),and the International Program of the Santa Fe Institute,NM,USA.
文摘Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized patterns that emerge from the interactions of individual modules. Interactions include both competition and cooperation,and several types of positive and negative feedback loops are involved. Development can be open to external influences, thus enabling the plant to adjust its form to the environment,for example, to the spatial distribution of ecological resources. This paper provides a review on adaptive plasticity in plants.
