The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species （NIS） also have ...The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species （NIS） also have attracted much attention as opportunities to explore important eco-evolutionary processes such as rapid adaptation, long-distance dispersal and range expansion, and secondary contacts between divergent evolutionary lineages. In this context, genetic tools have been extensively used in the past 20 years. Three important issues appear to have emerged from such studies. First, the study of NIS has revealed unexpected cryptic diversity in what had previously been assumed homogeneous entities. Second, there has been surprisingly little evidence of strong founder events accompanying marine introductions, a pattern possibly driven by large propagule loads. Third, the evolutionary processes leading to successful invasion have been difficult to ascertain due to faint genetic signals. Here we explore the potential of novel tools associated with high-throughput sequencing （HTS） to address these still pressing issues. Dramatic increase in the number of loci accessible via HTS has the potential to radically increase the power of analyses aimed at species delineation, exploring the population genomic consequences of range expansions, and examining evolutionary processes such as admixture, introgression, and adaptation. Nevertheless, the value of this new wealth of genomic data will ultimately depend on the ability to couple it with expanded ＂traditional＂ efforts, including exhaustive sampling of marine populations over large geographic scales, integrated taxonomic analyses, and population level exploration of quantitative trait differentiation through common-garden and other laboratory experiments.展开更多
Is there an overriding principle of nature, hitherto overlooked, that governs all population behavior? A single principle that drives all the regimes observed in nature exponential-like growth, saturated growth, popul...Is there an overriding principle of nature, hitherto overlooked, that governs all population behavior? A single principle that drives all the regimes observed in nature exponential-like growth, saturated growth, population decline, population extinction, oscillatory behavior? In current orthodox population theory, this diverse range of population behaviors is described by many different equations each with its own specific justification. The signature of an overriding principle would be a differential equation which, in a single statement, embraces all the panoply of regimes. A candidate such governing equation is proposed. The principle from which the equation is derived is this: The effect on the environment of a population’s success is to alter that environment in a way that opposes the success.展开更多
Accurate understanding of global photosynthetic capacity(i.e.maximum RuBisCO carboxylation rate,Vc,max)variability is critical for improved simulations of terrestrial ecosystem photosynthesis metabolisms and carbon cy...Accurate understanding of global photosynthetic capacity(i.e.maximum RuBisCO carboxylation rate,Vc,max)variability is critical for improved simulations of terrestrial ecosystem photosynthesis metabolisms and carbon cycles with climate change,but a holistic understanding and assessment remains lacking.Here we hypothesized that V_(c,max)was dictated by both factors of temperature-associated enzyme kinetics(capturing instantaneous ecophysiological responses)and the amount of activated RuBisCO(indexed by V_(c,max)standardized at 25℃,V_(c,max25)),and compiled a comprehensive global dataset(n=7339 observations from 428 sites)for hypothesis testing.The photosynthesis data were derived from leaf gas exchange measurements using portable gas exchange systems.We found that a semi-empirical statistical model considering both factors explained 78%of global V_(c,max)variability,followed by 55%explained by enzyme kinetics alone.This statistical model outperformed the current theoretical optimality model for predicting global V_(c,max)variability(67%),primarily due to its poor characterization on global V_(c,max25)variability(3%).Further,we demonstrated that,in addition to climatic variables,belowground resource constraint on photosynthetic machinery built-up that directly structures the biogeography of V_(c,max25)was a key missing mechanism for improving the theoretical modelling of global V_(c,max)variability.These findings improve the mechanistic understanding of global V_(c,max)variability and provide an important basis to benchmark process-based models of terrestrial photosynthesis and carbon cycling under climate change.展开更多
文摘The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species （NIS） also have attracted much attention as opportunities to explore important eco-evolutionary processes such as rapid adaptation, long-distance dispersal and range expansion, and secondary contacts between divergent evolutionary lineages. In this context, genetic tools have been extensively used in the past 20 years. Three important issues appear to have emerged from such studies. First, the study of NIS has revealed unexpected cryptic diversity in what had previously been assumed homogeneous entities. Second, there has been surprisingly little evidence of strong founder events accompanying marine introductions, a pattern possibly driven by large propagule loads. Third, the evolutionary processes leading to successful invasion have been difficult to ascertain due to faint genetic signals. Here we explore the potential of novel tools associated with high-throughput sequencing （HTS） to address these still pressing issues. Dramatic increase in the number of loci accessible via HTS has the potential to radically increase the power of analyses aimed at species delineation, exploring the population genomic consequences of range expansions, and examining evolutionary processes such as admixture, introgression, and adaptation. Nevertheless, the value of this new wealth of genomic data will ultimately depend on the ability to couple it with expanded ＂traditional＂ efforts, including exhaustive sampling of marine populations over large geographic scales, integrated taxonomic analyses, and population level exploration of quantitative trait differentiation through common-garden and other laboratory experiments.
文摘Is there an overriding principle of nature, hitherto overlooked, that governs all population behavior? A single principle that drives all the regimes observed in nature exponential-like growth, saturated growth, population decline, population extinction, oscillatory behavior? In current orthodox population theory, this diverse range of population behaviors is described by many different equations each with its own specific justification. The signature of an overriding principle would be a differential equation which, in a single statement, embraces all the panoply of regimes. A candidate such governing equation is proposed. The principle from which the equation is derived is this: The effect on the environment of a population’s success is to alter that environment in a way that opposes the success.
基金supported by National Natural Science Foundation of China(31922090 and 31901086)Hong Kong Research Grant Council Early Career Scheme(27306020)+4 种基金HKU Seed Fund for Basic Research(201905159005 and 202011159154)supported by the Innovation and Technology Fund(funding support to State Key Laboratories in Hong Kong of Agorobiotechnology)of the HKSAR,Chinasupported by the Carbon Mitigation Initiative of the Princeton Universitysupport from the National Science Foundation(DEB-2045968)Texas Tech University.
文摘Accurate understanding of global photosynthetic capacity(i.e.maximum RuBisCO carboxylation rate,Vc,max)variability is critical for improved simulations of terrestrial ecosystem photosynthesis metabolisms and carbon cycles with climate change,but a holistic understanding and assessment remains lacking.Here we hypothesized that V_(c,max)was dictated by both factors of temperature-associated enzyme kinetics(capturing instantaneous ecophysiological responses)and the amount of activated RuBisCO(indexed by V_(c,max)standardized at 25℃,V_(c,max25)),and compiled a comprehensive global dataset(n=7339 observations from 428 sites)for hypothesis testing.The photosynthesis data were derived from leaf gas exchange measurements using portable gas exchange systems.We found that a semi-empirical statistical model considering both factors explained 78%of global V_(c,max)variability,followed by 55%explained by enzyme kinetics alone.This statistical model outperformed the current theoretical optimality model for predicting global V_(c,max)variability(67%),primarily due to its poor characterization on global V_(c,max25)variability(3%).Further,we demonstrated that,in addition to climatic variables,belowground resource constraint on photosynthetic machinery built-up that directly structures the biogeography of V_(c,max25)was a key missing mechanism for improving the theoretical modelling of global V_(c,max)variability.These findings improve the mechanistic understanding of global V_(c,max)variability and provide an important basis to benchmark process-based models of terrestrial photosynthesis and carbon cycling under climate change.
