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Joseph A. Cook - One of the best experts on this subject based on the ideXlab platform.
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Post-glacial colonization of northwestern North America by Blackwell Science, Ltd the forest-associated American marten (Martes Americana,
2013Co-Authors: Mammalia Carnivora Mustelidae, Rodney W Flynn, Karen D. Stone, Joseph A. CookAbstract:Phylogeographic patterns were used to assess intraspecific diversification of American martens (Martes Americana). Within martens, two morphological groups (Americana and caurina) have been recognized, though the level of distinction between them has been debated. We examined mitochondrial cytochrome b gene haplotypes from 680 martens to explore the colonization history of the Pacific Northwest and found two clades that correspond to the morphological groups. The widespread Americana clade extends from interior Alaska south to Montana and eastward to Newfoundland and New England (i.e. northwestern, north-central and northeastern North America). The caurina clade occurs in western North America, minimally extending from Admiralty Island (southeastern Alaska) south to Oregon and Wyoming. Our data indicated two colonization events for the Pacific Northwest (one by members of each clade) and were consistent with the persistence of populations throughout past glacial periods in eastern and western refugia. Due to vegetational and geological history following the past deglaciation, we hypothesize that martens of the caurina clade spread along the North Pacific Coast, and into southeastern Alaska, earlie
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post glacial colonization of northwestern north america by the forest associated american marten Martes Americana mammalia carnivora mustelidae
Molecular Ecology, 2002Co-Authors: Karen D. Stone, Rodney W Flynn, Joseph A. CookAbstract:Phylogeographic patterns were used to assess intraspecific diversification of American martens (Martes Americana). Within martens, two morphological groups (Americana and caurina) have been recognized, though the level of distinction between them has been debated. We examined mitochondrial cytochrome b gene haplotypes from 680 martens to explore the colonization history of the Pacific Northwest and found two clades that correspond to the morphological groups. The widespread Americana clade extends from interior Alaska south to Montana and eastward to Newfoundland and New England (i.e. northwestern, north-central and northeastern North America). The caurina clade occurs in western North America, minimally extending from Admiralty Island (southeastern Alaska) south to Oregon and Wyoming. Our data indicated two colonization events for the Pacific Northwest (one by members of each clade) and were consistent with the persistence of populations throughout past glacial periods in eastern and western refugia. Due to vegetational and geological history following the past deglaciation, we hypothesize that martens of the caurina clade spread along the North Pacific Coast, and into southeastern Alaska, earlier than martens of the Americana clade. Mismatch distributions for the Americana clade were indicative of populations that recently experienced demographic expansion, while mismatch distributions for the caurina clade suggested that populations were at equilibrium. These clades are reciprocally monophyletic and distinctive (interclade divergence ranged from 2.5 to 3.0% (uncorrected p), whereas, intraclade divergence was < 0.7%), and two regions of sympatry have been identified. Genetic signatures of past admixture in hybrid zones may have been extinguished during subsequent glacial periods when ranges contracted. This recurrent pattern of relatively restricted western, or Pacific coastal, lineages and more widespread eastern, or interior continental, lineages exists across broad taxonomic groups and suggests a shared biogeographical history.
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molecular evolution of holarctic martens genus Martes mammalia carnivora mustelidae
Molecular Phylogenetics and Evolution, 2002Co-Authors: Karen D. Stone, Joseph A. CookAbstract:Abstract The Bering Land Bridge has served as a major corridor of interchange between the northern continents for many organisms. We investigated the phylogeny of all extant species of Martes (except for Martes gwatkinsi from India) to infer evolutionary relationships and characterize the extent of trans-Beringian movements. Analyses of complete sequences of the mitochondrial cytochrome b gene and partial sequences of the nuclear aldolase C gene (241 bp) suggested that the genus Martes may be paraphyletic with respect to Gulo gulo . These data supported the fossil record's indication that early radiations gave rise to two subgenera ( Pekania and Charronia ) and that a more recent, possibly rapid, radiation gave rise to species of the third subgenus ( Martes ). Two colonizations of North America are evident, one by members of the subgenus Pekania and another by member of the subgenus Martes . Contrary to hypotheses based on morphological evidence, the “Americana” and “caurina” subspecies groups of Martes Americana are not the result of independent colonizations of North America. The phylogenetic analyses of cytochrome b data were consistent with the recognition of these subspecies groups as monophyletic clades; however, variation in the aldolase C sequences indicated that these generally parapatric groups may interbreed in a region of limited geographic overlap.
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MOLECULAR PHYLOGENETICS AND EVOLUTION
2001Co-Authors: Www. Academicpress. Com, Karen D. Stone, Joseph A. CookAbstract:The Bering Land Bridge has served as a major corridor of interchange between the northern continents for many organisms. We investigated the phylogeny of all extant species of Martes (except for Martes gwatkinsi from India) to infer evolutionary relationships and characterize the extent of trans-Beringian movements. Analyses of complete sequences of the mitochondrial cytochrome b gene and partial sequences of the nuclear aldolase C gene (241 bp) suggested that the genus Martes may be paraphyletic with respect to Gulo gulo. These data supported the fossil record’s indication that early radiations gave rise to two subgenera (Pekania and Charronia) and that a more recent, possibly rapid, radiation gave rise to species of the third subgenus (Martes). Two colonizations of North America are evident, one by members of the subgenus Pekania and another by member of the subgenus Martes. Contrary to hypotheses based on morphological evidence, the ‘‘Americana’ ’ and ‘‘caurina’ ’ subspecies groups of Martes Americana are not the result of independent colonizations of North America. The phylogenetic analyses of cytochrome b data were consistent with the recognition of these subspecies groups as monophyletic clades; however, variation in the aldolase C sequences indicated that these generally parapatric groups may interbreed in a region of limited geographic overlap. Ó 2002 Elsevier Science (USA). All rights reserved
John M Fryxell - One of the best experts on this subject based on the ideXlab platform.
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Blackwell Publishing LtdDispersal and genetic structure in the American marten,
2015Co-Authors: Martes Americana, C A Johnson, E Petit, I Thompson, John M FryxellAbstract:Natal dispersal in a vagile carnivore, the American marten ( Martes Americana), was studied by comparing radio-tracking data and microsatellite genetic structure in two populations occupying contrasting habitats. The genetic differentiation determined among groups of individuals using
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habitat mediated variation in predation risk by the american marten
Ecology, 2008Co-Authors: Mark Andruskiw, Ian D Thompson, John M Fryxell, James A BakerAbstract:The probability of prey encounter, attack, capture, and kill are often hypothesized to depend on habitat structure, but field evidence in terrestrial systems is rare. We tested whether predation efficiency by the American marten (Martes Americana) and fear of predation by their primary prey, the red-backed vole (Clethrionomys gapperi), differed between 20- to 50-year-old regenerating forest stands and older uncut stands. Our results showed that the frequency of prey encounter, prey attack, and prey kill were higher in old uncut forests, despite the fact that small-mammal density was similar to that in younger logged forests. These differences in predation efficiency were linked to higher abundance of coarse woody debris, which seems to offer sensory cues to martens, thereby increasing the odds of hunting success. Red-backed voles in regenerating forest stands exhibited increased wariness compared to voles living in old uncut forest, suggestive of a behavioral response to habitat-mediated variation in predation risk.
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dispersal and genetic structure in the american marten Martes Americana
Molecular Ecology, 2006Co-Authors: Thomas Broquet, C A Johnson, Eric J Petit, Ian D Thompson, Francoise Burel, John M FryxellAbstract:Natal dispersal in a vagile carnivore, the American marten ( Martes Americana ), was studied by comparing radio-tracking data and microsatellite genetic structure in two populations occupying contrasting habitats. The genetic differentiation determined among groups of individuals using F ST indices appeared to be weak in both landscapes, and showed no increase with geographical distance. Genetic structure investigated using pairwise genetic distances between individuals conversely showed a pattern of isolation by distance (IBD), but only in the population occurring in a homogeneous high-quality habitat, therefore showing the advantage of individual-based analyses in detecting within-population processes and local landscape effects. The telemetry study of juveniles revealed a leptokurtic distribution of dispersal distances in both populations, and estimates of the mean squared parent– offspring axial distance (σ 2 ) inferred both from the genetic pattern of IBD and from the
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Genetic isolation by distance and landscape connectivity in the American marten (Martes Americana)
Landscape Ecology, 2006Co-Authors: Thomas Broquet, Eric J Petit, John M Fryxell, Nicolas Ray, Francoise BurelAbstract:Empirical studies of landscape connectivity are limited by the difficulty of directly measuring animal movement. ‘Indirect' approaches involving genetic analyses provide a complementary tool to ‘direct' methods such as capture–recapture or radio-tracking. Here the effect of landscape on dispersal was investigated in a forest-dwelling species, the American marten (Martes Americana) using the genetic model of isolation by distance (IBD). This model assumes isotropic dispersal in a homogeneous environment and is characterized by increasing genetic differentiation among individuals separated by increasing geographic distances. The effect of landscape features on this genetic pattern was used to test for a departure from spatially homogeneous dispersal. This study was conducted on two populations in homogeneous vs. heterogeneous habitat in a harvested boreal forest in Ontario (Canada). A pattern of IBD was evidenced in the homogeneous landscape whereas no such pattern was found in the near-by harvested forest. To test whether landscape structure may be accountable for this difference, we used effective distances that take into account the effect of landscape features on marten movement instead of Euclidean distances in the model of isolation by distance. Effective distances computed using least-cost modeling were better correlated to genetic distances in both landscapes, thereby showing that the interaction between landscape features and dispersal in Martes Americana may be detected through individual-based analyses of spatial genetic structure. However, the simplifying assumptions of genetic models and the low proportions in genetic differentiation explained by these models may limit their utility in quantifying the effect of landscape structure.
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Research Article Genetic isolation by distance and landscape connectivity in the
2005Co-Authors: Thomas Broquet, Nicolas Ray, Eric Petit, John M FryxellAbstract:American marten (Martes Americana
Karen D. Stone - One of the best experts on this subject based on the ideXlab platform.
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Post-glacial colonization of northwestern North America by Blackwell Science, Ltd the forest-associated American marten (Martes Americana,
2013Co-Authors: Mammalia Carnivora Mustelidae, Rodney W Flynn, Karen D. Stone, Joseph A. CookAbstract:Phylogeographic patterns were used to assess intraspecific diversification of American martens (Martes Americana). Within martens, two morphological groups (Americana and caurina) have been recognized, though the level of distinction between them has been debated. We examined mitochondrial cytochrome b gene haplotypes from 680 martens to explore the colonization history of the Pacific Northwest and found two clades that correspond to the morphological groups. The widespread Americana clade extends from interior Alaska south to Montana and eastward to Newfoundland and New England (i.e. northwestern, north-central and northeastern North America). The caurina clade occurs in western North America, minimally extending from Admiralty Island (southeastern Alaska) south to Oregon and Wyoming. Our data indicated two colonization events for the Pacific Northwest (one by members of each clade) and were consistent with the persistence of populations throughout past glacial periods in eastern and western refugia. Due to vegetational and geological history following the past deglaciation, we hypothesize that martens of the caurina clade spread along the North Pacific Coast, and into southeastern Alaska, earlie
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post glacial colonization of northwestern north america by the forest associated american marten Martes Americana mammalia carnivora mustelidae
Molecular Ecology, 2002Co-Authors: Karen D. Stone, Rodney W Flynn, Joseph A. CookAbstract:Phylogeographic patterns were used to assess intraspecific diversification of American martens (Martes Americana). Within martens, two morphological groups (Americana and caurina) have been recognized, though the level of distinction between them has been debated. We examined mitochondrial cytochrome b gene haplotypes from 680 martens to explore the colonization history of the Pacific Northwest and found two clades that correspond to the morphological groups. The widespread Americana clade extends from interior Alaska south to Montana and eastward to Newfoundland and New England (i.e. northwestern, north-central and northeastern North America). The caurina clade occurs in western North America, minimally extending from Admiralty Island (southeastern Alaska) south to Oregon and Wyoming. Our data indicated two colonization events for the Pacific Northwest (one by members of each clade) and were consistent with the persistence of populations throughout past glacial periods in eastern and western refugia. Due to vegetational and geological history following the past deglaciation, we hypothesize that martens of the caurina clade spread along the North Pacific Coast, and into southeastern Alaska, earlier than martens of the Americana clade. Mismatch distributions for the Americana clade were indicative of populations that recently experienced demographic expansion, while mismatch distributions for the caurina clade suggested that populations were at equilibrium. These clades are reciprocally monophyletic and distinctive (interclade divergence ranged from 2.5 to 3.0% (uncorrected p), whereas, intraclade divergence was < 0.7%), and two regions of sympatry have been identified. Genetic signatures of past admixture in hybrid zones may have been extinguished during subsequent glacial periods when ranges contracted. This recurrent pattern of relatively restricted western, or Pacific coastal, lineages and more widespread eastern, or interior continental, lineages exists across broad taxonomic groups and suggests a shared biogeographical history.
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molecular evolution of holarctic martens genus Martes mammalia carnivora mustelidae
Molecular Phylogenetics and Evolution, 2002Co-Authors: Karen D. Stone, Joseph A. CookAbstract:Abstract The Bering Land Bridge has served as a major corridor of interchange between the northern continents for many organisms. We investigated the phylogeny of all extant species of Martes (except for Martes gwatkinsi from India) to infer evolutionary relationships and characterize the extent of trans-Beringian movements. Analyses of complete sequences of the mitochondrial cytochrome b gene and partial sequences of the nuclear aldolase C gene (241 bp) suggested that the genus Martes may be paraphyletic with respect to Gulo gulo . These data supported the fossil record's indication that early radiations gave rise to two subgenera ( Pekania and Charronia ) and that a more recent, possibly rapid, radiation gave rise to species of the third subgenus ( Martes ). Two colonizations of North America are evident, one by members of the subgenus Pekania and another by member of the subgenus Martes . Contrary to hypotheses based on morphological evidence, the “Americana” and “caurina” subspecies groups of Martes Americana are not the result of independent colonizations of North America. The phylogenetic analyses of cytochrome b data were consistent with the recognition of these subspecies groups as monophyletic clades; however, variation in the aldolase C sequences indicated that these generally parapatric groups may interbreed in a region of limited geographic overlap.
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MOLECULAR PHYLOGENETICS AND EVOLUTION
2001Co-Authors: Www. Academicpress. Com, Karen D. Stone, Joseph A. CookAbstract:The Bering Land Bridge has served as a major corridor of interchange between the northern continents for many organisms. We investigated the phylogeny of all extant species of Martes (except for Martes gwatkinsi from India) to infer evolutionary relationships and characterize the extent of trans-Beringian movements. Analyses of complete sequences of the mitochondrial cytochrome b gene and partial sequences of the nuclear aldolase C gene (241 bp) suggested that the genus Martes may be paraphyletic with respect to Gulo gulo. These data supported the fossil record’s indication that early radiations gave rise to two subgenera (Pekania and Charronia) and that a more recent, possibly rapid, radiation gave rise to species of the third subgenus (Martes). Two colonizations of North America are evident, one by members of the subgenus Pekania and another by member of the subgenus Martes. Contrary to hypotheses based on morphological evidence, the ‘‘Americana’ ’ and ‘‘caurina’ ’ subspecies groups of Martes Americana are not the result of independent colonizations of North America. The phylogenetic analyses of cytochrome b data were consistent with the recognition of these subspecies groups as monophyletic clades; however, variation in the aldolase C sequences indicated that these generally parapatric groups may interbreed in a region of limited geographic overlap. Ó 2002 Elsevier Science (USA). All rights reserved
Francoise Burel - One of the best experts on this subject based on the ideXlab platform.
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dispersal and genetic structure in the american marten Martes Americana
Molecular Ecology, 2006Co-Authors: Thomas Broquet, C A Johnson, Eric J Petit, Ian D Thompson, Francoise Burel, John M FryxellAbstract:Natal dispersal in a vagile carnivore, the American marten ( Martes Americana ), was studied by comparing radio-tracking data and microsatellite genetic structure in two populations occupying contrasting habitats. The genetic differentiation determined among groups of individuals using F ST indices appeared to be weak in both landscapes, and showed no increase with geographical distance. Genetic structure investigated using pairwise genetic distances between individuals conversely showed a pattern of isolation by distance (IBD), but only in the population occurring in a homogeneous high-quality habitat, therefore showing the advantage of individual-based analyses in detecting within-population processes and local landscape effects. The telemetry study of juveniles revealed a leptokurtic distribution of dispersal distances in both populations, and estimates of the mean squared parent– offspring axial distance (σ 2 ) inferred both from the genetic pattern of IBD and from the
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Genetic isolation by distance and landscape connectivity in the American marten (Martes Americana)
Landscape Ecology, 2006Co-Authors: Thomas Broquet, Eric J Petit, John M Fryxell, Nicolas Ray, Francoise BurelAbstract:Empirical studies of landscape connectivity are limited by the difficulty of directly measuring animal movement. ‘Indirect' approaches involving genetic analyses provide a complementary tool to ‘direct' methods such as capture–recapture or radio-tracking. Here the effect of landscape on dispersal was investigated in a forest-dwelling species, the American marten (Martes Americana) using the genetic model of isolation by distance (IBD). This model assumes isotropic dispersal in a homogeneous environment and is characterized by increasing genetic differentiation among individuals separated by increasing geographic distances. The effect of landscape features on this genetic pattern was used to test for a departure from spatially homogeneous dispersal. This study was conducted on two populations in homogeneous vs. heterogeneous habitat in a harvested boreal forest in Ontario (Canada). A pattern of IBD was evidenced in the homogeneous landscape whereas no such pattern was found in the near-by harvested forest. To test whether landscape structure may be accountable for this difference, we used effective distances that take into account the effect of landscape features on marten movement instead of Euclidean distances in the model of isolation by distance. Effective distances computed using least-cost modeling were better correlated to genetic distances in both landscapes, thereby showing that the interaction between landscape features and dispersal in Martes Americana may be detected through individual-based analyses of spatial genetic structure. However, the simplifying assumptions of genetic models and the low proportions in genetic differentiation explained by these models may limit their utility in quantifying the effect of landscape structure.
Thomas Broquet - One of the best experts on this subject based on the ideXlab platform.
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dispersal and genetic structure in the american marten Martes Americana
Molecular Ecology, 2006Co-Authors: Thomas Broquet, C A Johnson, Eric J Petit, Ian D Thompson, Francoise Burel, John M FryxellAbstract:Natal dispersal in a vagile carnivore, the American marten ( Martes Americana ), was studied by comparing radio-tracking data and microsatellite genetic structure in two populations occupying contrasting habitats. The genetic differentiation determined among groups of individuals using F ST indices appeared to be weak in both landscapes, and showed no increase with geographical distance. Genetic structure investigated using pairwise genetic distances between individuals conversely showed a pattern of isolation by distance (IBD), but only in the population occurring in a homogeneous high-quality habitat, therefore showing the advantage of individual-based analyses in detecting within-population processes and local landscape effects. The telemetry study of juveniles revealed a leptokurtic distribution of dispersal distances in both populations, and estimates of the mean squared parent– offspring axial distance (σ 2 ) inferred both from the genetic pattern of IBD and from the
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Genetic isolation by distance and landscape connectivity in the American marten (Martes Americana)
Landscape Ecology, 2006Co-Authors: Thomas Broquet, Eric J Petit, John M Fryxell, Nicolas Ray, Francoise BurelAbstract:Empirical studies of landscape connectivity are limited by the difficulty of directly measuring animal movement. ‘Indirect' approaches involving genetic analyses provide a complementary tool to ‘direct' methods such as capture–recapture or radio-tracking. Here the effect of landscape on dispersal was investigated in a forest-dwelling species, the American marten (Martes Americana) using the genetic model of isolation by distance (IBD). This model assumes isotropic dispersal in a homogeneous environment and is characterized by increasing genetic differentiation among individuals separated by increasing geographic distances. The effect of landscape features on this genetic pattern was used to test for a departure from spatially homogeneous dispersal. This study was conducted on two populations in homogeneous vs. heterogeneous habitat in a harvested boreal forest in Ontario (Canada). A pattern of IBD was evidenced in the homogeneous landscape whereas no such pattern was found in the near-by harvested forest. To test whether landscape structure may be accountable for this difference, we used effective distances that take into account the effect of landscape features on marten movement instead of Euclidean distances in the model of isolation by distance. Effective distances computed using least-cost modeling were better correlated to genetic distances in both landscapes, thereby showing that the interaction between landscape features and dispersal in Martes Americana may be detected through individual-based analyses of spatial genetic structure. However, the simplifying assumptions of genetic models and the low proportions in genetic differentiation explained by these models may limit their utility in quantifying the effect of landscape structure.
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Research Article Genetic isolation by distance and landscape connectivity in the
2005Co-Authors: Thomas Broquet, Nicolas Ray, Eric Petit, John M FryxellAbstract:American marten (Martes Americana