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Om P Rajora - One of the best experts on this subject based on the ideXlab platform.
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post glacial phylogeography and evolution of a wide ranging highly exploited keystone forest tree eastern white pine pinus strobus in north america single refugium multiple routes
BMC Evolutionary Biology, 2016Co-Authors: John W R Zinck, Om P RajoraAbstract:Knowledge of the historical distribution and postglacial phylogeography and evolution of a species is important to better understand its current distribution and population structure and potential fate in the future, especially under climate change conditions, and conservation of its genetic resources. We have addressed this issue in a wide-ranging and heavily exploited keystone forest tree species of eastern North America, eastern white pine (Pinus strobus). We examined the range-wide population genetic structure, tested various hypothetical population history and evolutionary scenarios and inferred the location of glacial refugium and post-glacial Recolonization routes. Our hypothesis was that eastern white pine survived in a single glacial refugium and expanded through multiple post-glacial Recolonization routes. We studied the range-wide genetic diversity and population structure of 33 eastern white pine populations using 12 nuclear and 3 chloroplast microsatellite DNA markers. We used Approximate Bayesian Computation approach to test various evolutionary scenarios. We observed high levels of genetic diversity, and significant genetic differentiation (F ST = 0.104) and population structure among eastern white pine populations across its range. A south to north trend of declining genetic diversity existed, consistent with repeated founder effects during post-glaciation migration northwards. We observed broad consensus from nuclear and chloroplast genetic markers supporting the presence of two main post-glacial Recolonization routes that originated from a single southern refugium in the mid-Atlantic plain. One route gave rise to populations at the western margin of the species’ range in Minnesota and western Ontario. The second route gave rise to central-eastern populations, which branched into two subgroups: central and eastern. We observed minimal sharing of chloroplast haplotypes between Recolonization routes but there was evidence of admixture between the western and west-central populations. Our study reveals a single southern refugium, two Recolonization routes and three genetically distinguishable lineages in eastern white pine that we suggest to be treated as separate Evolutionarily Significant Units. Like many wide-ranging North American species, eastern white pine retains the genetic signatures of post-glacial Recolonization and evolution, and its contemporary population genetic structure reflects not just the modern distribution and effects of heavy exploitation but also routes northward from its glacial refugium.
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Post-glacial phylogeography and evolution of a wide-ranging highly-exploited keystone forest tree, eastern white pine (Pinus strobus) in North America: single refugium, multiple routes
BMC Evolutionary Biology, 2016Co-Authors: John W R Zinck, Om P RajoraAbstract:Background Knowledge of the historical distribution and postglacial phylogeography and evolution of a species is important to better understand its current distribution and population structure and potential fate in the future, especially under climate change conditions, and conservation of its genetic resources. We have addressed this issue in a wide-ranging and heavily exploited keystone forest tree species of eastern North America, eastern white pine ( Pinus strobus ). We examined the range-wide population genetic structure, tested various hypothetical population history and evolutionary scenarios and inferred the location of glacial refugium and post-glacial Recolonization routes. Our hypothesis was that eastern white pine survived in a single glacial refugium and expanded through multiple post-glacial Recolonization routes. Results We studied the range-wide genetic diversity and population structure of 33 eastern white pine populations using 12 nuclear and 3 chloroplast microsatellite DNA markers. We used Approximate Bayesian Computation approach to test various evolutionary scenarios. We observed high levels of genetic diversity, and significant genetic differentiation ( F _ST = 0.104) and population structure among eastern white pine populations across its range. A south to north trend of declining genetic diversity existed, consistent with repeated founder effects during post-glaciation migration northwards. We observed broad consensus from nuclear and chloroplast genetic markers supporting the presence of two main post-glacial Recolonization routes that originated from a single southern refugium in the mid-Atlantic plain. One route gave rise to populations at the western margin of the species’ range in Minnesota and western Ontario. The second route gave rise to central-eastern populations, which branched into two subgroups: central and eastern. We observed minimal sharing of chloroplast haplotypes between Recolonization routes but there was evidence of admixture between the western and west-central populations. Conclusions Our study reveals a single southern refugium, two Recolonization routes and three genetically distinguishable lineages in eastern white pine that we suggest to be treated as separate Evolutionarily Significant Units. Like many wide-ranging North American species, eastern white pine retains the genetic signatures of post-glacial Recolonization and evolution, and its contemporary population genetic structure reflects not just the modern distribution and effects of heavy exploitation but also routes northward from its glacial refugium.
Mohammed Ariful Islam - One of the best experts on this subject based on the ideXlab platform.
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spatial avoidance inhibition of Recolonization and population isolation in zebrafish danio rerio caused by copper exposure under a non forced approach
Science of The Total Environment, 2019Co-Authors: Mohammed Ariful Islam, Julian Blasco, Cristiano V M AraujoAbstract:Abstract Aquatic ecosystems receive run-off and discharges from different sources that lead to the accumulation of contaminants such as copper. Besides producing lethal and sub-lethal effects, copper has shown to be aversive to zebrafish (Danio rerio) by triggering avoidance response. The primary aim of the present study was to evaluate how a copper gradient could affect the spatial distribution of D. rerio by triggering avoidance, preventing Recolonization and isolating populations. Secondly, to what extent the food availability in a previously avoided environment could make it a less aversive environment was assessed. A non-forced, multi-compartmented exposure system with a copper gradient (0–300 μg·L−1), through which fish could move, was used for the avoidance and Recolonization assays. To test the effect of copper on population isolation, two uncontaminated connected zones were separated by a chemical barrier with a copper concentration of 90 μg·L−1 (a concentration producing an avoidance of 50% - AC50). Zebrafish avoided copper and the 2 h-AC50 was 90.8 μg·L−1. The Recolonization was in accordance with avoidance and the relationship ACx/RC100-x (RC: Recolonization concentration) was around 2.5. When food was provided in the highest copper concentration, the Recolonization pattern was altered, although the distribution of the fish was not statistically different from the scenario without food. The chemical barrier formed by copper (90 μg·L−1) impaired the migratory potential of the fish population by 41.3%; when food was provided in the last compartment, no statistically significant trend of fish moving towards that concentration was observed. Copper might act as an environmental disruptor by triggering spatial avoidance, preventing Recolonization and isolating populations in zebrafish. The present study allows simultaneously including three ecological concepts to ecotoxicological studies that have received little attention: habitat selection, Recolonization and habitat chemical fragmentation.
Cristiano V M Araujo - One of the best experts on this subject based on the ideXlab platform.
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spatial avoidance inhibition of Recolonization and population isolation in zebrafish danio rerio caused by copper exposure under a non forced approach
Science of The Total Environment, 2019Co-Authors: Mohammed Ariful Islam, Julian Blasco, Cristiano V M AraujoAbstract:Abstract Aquatic ecosystems receive run-off and discharges from different sources that lead to the accumulation of contaminants such as copper. Besides producing lethal and sub-lethal effects, copper has shown to be aversive to zebrafish (Danio rerio) by triggering avoidance response. The primary aim of the present study was to evaluate how a copper gradient could affect the spatial distribution of D. rerio by triggering avoidance, preventing Recolonization and isolating populations. Secondly, to what extent the food availability in a previously avoided environment could make it a less aversive environment was assessed. A non-forced, multi-compartmented exposure system with a copper gradient (0–300 μg·L−1), through which fish could move, was used for the avoidance and Recolonization assays. To test the effect of copper on population isolation, two uncontaminated connected zones were separated by a chemical barrier with a copper concentration of 90 μg·L−1 (a concentration producing an avoidance of 50% - AC50). Zebrafish avoided copper and the 2 h-AC50 was 90.8 μg·L−1. The Recolonization was in accordance with avoidance and the relationship ACx/RC100-x (RC: Recolonization concentration) was around 2.5. When food was provided in the highest copper concentration, the Recolonization pattern was altered, although the distribution of the fish was not statistically different from the scenario without food. The chemical barrier formed by copper (90 μg·L−1) impaired the migratory potential of the fish population by 41.3%; when food was provided in the last compartment, no statistically significant trend of fish moving towards that concentration was observed. Copper might act as an environmental disruptor by triggering spatial avoidance, preventing Recolonization and isolating populations in zebrafish. The present study allows simultaneously including three ecological concepts to ecotoxicological studies that have received little attention: habitat selection, Recolonization and habitat chemical fragmentation.
John W R Zinck - One of the best experts on this subject based on the ideXlab platform.
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post glacial phylogeography and evolution of a wide ranging highly exploited keystone forest tree eastern white pine pinus strobus in north america single refugium multiple routes
BMC Evolutionary Biology, 2016Co-Authors: John W R Zinck, Om P RajoraAbstract:Knowledge of the historical distribution and postglacial phylogeography and evolution of a species is important to better understand its current distribution and population structure and potential fate in the future, especially under climate change conditions, and conservation of its genetic resources. We have addressed this issue in a wide-ranging and heavily exploited keystone forest tree species of eastern North America, eastern white pine (Pinus strobus). We examined the range-wide population genetic structure, tested various hypothetical population history and evolutionary scenarios and inferred the location of glacial refugium and post-glacial Recolonization routes. Our hypothesis was that eastern white pine survived in a single glacial refugium and expanded through multiple post-glacial Recolonization routes. We studied the range-wide genetic diversity and population structure of 33 eastern white pine populations using 12 nuclear and 3 chloroplast microsatellite DNA markers. We used Approximate Bayesian Computation approach to test various evolutionary scenarios. We observed high levels of genetic diversity, and significant genetic differentiation (F ST = 0.104) and population structure among eastern white pine populations across its range. A south to north trend of declining genetic diversity existed, consistent with repeated founder effects during post-glaciation migration northwards. We observed broad consensus from nuclear and chloroplast genetic markers supporting the presence of two main post-glacial Recolonization routes that originated from a single southern refugium in the mid-Atlantic plain. One route gave rise to populations at the western margin of the species’ range in Minnesota and western Ontario. The second route gave rise to central-eastern populations, which branched into two subgroups: central and eastern. We observed minimal sharing of chloroplast haplotypes between Recolonization routes but there was evidence of admixture between the western and west-central populations. Our study reveals a single southern refugium, two Recolonization routes and three genetically distinguishable lineages in eastern white pine that we suggest to be treated as separate Evolutionarily Significant Units. Like many wide-ranging North American species, eastern white pine retains the genetic signatures of post-glacial Recolonization and evolution, and its contemporary population genetic structure reflects not just the modern distribution and effects of heavy exploitation but also routes northward from its glacial refugium.
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Post-glacial phylogeography and evolution of a wide-ranging highly-exploited keystone forest tree, eastern white pine (Pinus strobus) in North America: single refugium, multiple routes
BMC Evolutionary Biology, 2016Co-Authors: John W R Zinck, Om P RajoraAbstract:Background Knowledge of the historical distribution and postglacial phylogeography and evolution of a species is important to better understand its current distribution and population structure and potential fate in the future, especially under climate change conditions, and conservation of its genetic resources. We have addressed this issue in a wide-ranging and heavily exploited keystone forest tree species of eastern North America, eastern white pine ( Pinus strobus ). We examined the range-wide population genetic structure, tested various hypothetical population history and evolutionary scenarios and inferred the location of glacial refugium and post-glacial Recolonization routes. Our hypothesis was that eastern white pine survived in a single glacial refugium and expanded through multiple post-glacial Recolonization routes. Results We studied the range-wide genetic diversity and population structure of 33 eastern white pine populations using 12 nuclear and 3 chloroplast microsatellite DNA markers. We used Approximate Bayesian Computation approach to test various evolutionary scenarios. We observed high levels of genetic diversity, and significant genetic differentiation ( F _ST = 0.104) and population structure among eastern white pine populations across its range. A south to north trend of declining genetic diversity existed, consistent with repeated founder effects during post-glaciation migration northwards. We observed broad consensus from nuclear and chloroplast genetic markers supporting the presence of two main post-glacial Recolonization routes that originated from a single southern refugium in the mid-Atlantic plain. One route gave rise to populations at the western margin of the species’ range in Minnesota and western Ontario. The second route gave rise to central-eastern populations, which branched into two subgroups: central and eastern. We observed minimal sharing of chloroplast haplotypes between Recolonization routes but there was evidence of admixture between the western and west-central populations. Conclusions Our study reveals a single southern refugium, two Recolonization routes and three genetically distinguishable lineages in eastern white pine that we suggest to be treated as separate Evolutionarily Significant Units. Like many wide-ranging North American species, eastern white pine retains the genetic signatures of post-glacial Recolonization and evolution, and its contemporary population genetic structure reflects not just the modern distribution and effects of heavy exploitation but also routes northward from its glacial refugium.
Paulo Da Cunha Lana - One of the best experts on this subject based on the ideXlab platform.
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Distance from rocky shores affects infaunal Recolonization in a subtropical tidal flat
Hydrobiologia, 2019Co-Authors: Joao B. Gusmao, Leonardo Sandrini-neto, Paulo Da Cunha LanaAbstract:Hard bottoms can negatively affect the surrounding infauna by hosting predatory fauna and modifying local hydrodynamics and sedimentation rates. Considering that these effects depend on the distance to the hard bottoms, we expected that the infaunal structure and Recolonization would change accordingly. We assessed whether the distance from a rocky shore alters infaunal Recolonization in a subtropical tidal flat. Sediment was defaunated on sites near and far from a rocky shore and the subsequent faunal Recolonization was followed for 40 days. The sites near and far from the rocky shore displayed different assemblage structures, which we attributed to local variation in hydrodynamic conditions. Both the total infaunal abundance and the abundance of the dominant species recovered faster at the near site. We indicate that changes in infaunal Recolonization at varying distances from natural rocky shores are primarily driven by the availability of adults. Infaunal recovery took less than 2 weeks, but Recolonization rates increased near the rocky shore, as a function of its naturally variable assemblage structure and relatively lower species richness and abundances. We suggest that models of infaunal distribution and Recolonization should incorporate landscape features such as the presence and distance from rocky bottoms.
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Reciprocal experimental transplantations to assess effects of organic enrichment on the Recolonization of benthic macrofauna in a subtropical estuary
Marine Pollution Bulletin, 2012Co-Authors: Fabiana Regina Gern, Paulo Da Cunha LanaAbstract:Coastal benthic habitats are usually in a state of continuous Recolonization as a consequence of natural disturbances or human activities. Recolonization patterns can be strongly affected by the quality of the sediment. We evaluated herein the macrobenthic Recolonization of organically enriched sediments through a manipulative experiment involving reciprocal transplants between contaminated and non-contaminated intertidal areas. Regardless of the experimental treatments, the density of the polychaete Capitella sp. was extremely high in the contaminated area as well as the density of the gastropod Cylichna sp. in the non-contaminated area. We rejected the hypothesis that differences in sediment quality would determine macrofaunal Recolonization at least in the considered scales of space in meters and time in weeks. The Recolonization process in a subtropical estuarine environment was strongly dependent on the migration of adults present in the sediments adjacent to the experimental units.
