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Brett R. Riddle - One of the best experts on this subject based on the ideXlab platform.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus, a widely distributed western North American minnow
BMC Evolutionary Biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage. Results Genetic diversification in redside shiner began in the mid to late Pleistocene, but was not associated with LGM. Different clades of redside shiner were distributed in multiple glacial age refugia, and each clade retains a signature of population expansion, with clades having secondary contact in some areas. Conclusions Divergence times between redside shiner populations in the Bonneville Basin and the Upper Snake/Columbia River drainage precedes the Bonneville Flood, thus it is unlikely that redside shiner invaded the Bonneville Basin during this flooding event. All but one British Columbia population of redside shiner are associated with the Upper Columbia River drainage with the lone exception being a population near the coast, suggesting that the province as a whole was colonized from multiple refugia, but the inland British Columbia redside shiner populations are affiliated with a refugium in the Upper Columbia River drainage.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus , a widely distributed western North American minnow
BMC evolutionary biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage.
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The roles of Neogene geology and late Pleistocene lake levels in shaping the genetic structure of the Lahontan redside shiner Richardsonius egregius (Teleostei: Cyprinidae)
Biological Journal of the Linnean Society, 2011Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Shifting drainage patterns in western North America, shaped by geological activity and changing global climates, have influenced the evolution of many aquatic taxa. We investigated the role of late Pleistocene high stands in pluvial Lake Lahontan on the genetic structure of Richardsonius egregius, a minnow endemic to the Lahontan Basin of the western Great Basin. We used the mitochondrial cytochrome b gene to generate a phylogeny and assess intraspecific genetic diversity, to estimate divergence times between clades, and to evaluate whether gene flow currently occurs. The results obtained show that R. egregius exhibits genetic divergence between eastern and western Lahontan Basin populations. Divergence time estimates show that intraspecific genetic diversification began in the Pliocene or early Pleistocene, before the pluvial lake high stands associated with the last glacial maximum. These results imply that the fluctuating water levels in pluvial Lake Lahontan had a minimal effect on shaping the genetic architecture of R. egregius. Coalescent analyses using the immigration with migration model show that contemporary gene flow between eastern and western Lahontan Basin populations does not occur. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 163–176.
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Phylogenetic relationships of the western North American cyprinid genus Richardsonius, with an overview of phylogeographic structure.
Molecular phylogenetics and evolution, 2009Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Abstract Diversification of many North American taxa, including freshwater fishes, has been heavily influenced by the effects of complex geological and climatic events throughout the Cenozoic that have significantly altered the landscape. Here, we employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys . We also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within the group. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and Richardsonius , with Clinostomus being sister to an Iotichthys – Richardsonius clade, hence the currently recognized sister relationship between Clinostomus and Richardsonius is not supported. These genera appear to be monophyletic lineages, and sister species within genera appear to be reciprocally monophyletic. The two species within the genus Richardsonius both exhibit phylogeographic structure that is worthy of further investigation. Divergence time estimates between genera and species are Miocene or Pliocene in age, and divergence between phylogroups within species occurred in the late Pliocene to Pleistocene. These splits coincide with documented geological and climatic events.
Derek D. Houston - One of the best experts on this subject based on the ideXlab platform.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus, a widely distributed western North American minnow
BMC Evolutionary Biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage. Results Genetic diversification in redside shiner began in the mid to late Pleistocene, but was not associated with LGM. Different clades of redside shiner were distributed in multiple glacial age refugia, and each clade retains a signature of population expansion, with clades having secondary contact in some areas. Conclusions Divergence times between redside shiner populations in the Bonneville Basin and the Upper Snake/Columbia River drainage precedes the Bonneville Flood, thus it is unlikely that redside shiner invaded the Bonneville Basin during this flooding event. All but one British Columbia population of redside shiner are associated with the Upper Columbia River drainage with the lone exception being a population near the coast, suggesting that the province as a whole was colonized from multiple refugia, but the inland British Columbia redside shiner populations are affiliated with a refugium in the Upper Columbia River drainage.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus , a widely distributed western North American minnow
BMC evolutionary biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage.
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The roles of Neogene geology and late Pleistocene lake levels in shaping the genetic structure of the Lahontan redside shiner Richardsonius egregius (Teleostei: Cyprinidae)
Biological Journal of the Linnean Society, 2011Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Shifting drainage patterns in western North America, shaped by geological activity and changing global climates, have influenced the evolution of many aquatic taxa. We investigated the role of late Pleistocene high stands in pluvial Lake Lahontan on the genetic structure of Richardsonius egregius, a minnow endemic to the Lahontan Basin of the western Great Basin. We used the mitochondrial cytochrome b gene to generate a phylogeny and assess intraspecific genetic diversity, to estimate divergence times between clades, and to evaluate whether gene flow currently occurs. The results obtained show that R. egregius exhibits genetic divergence between eastern and western Lahontan Basin populations. Divergence time estimates show that intraspecific genetic diversification began in the Pliocene or early Pleistocene, before the pluvial lake high stands associated with the last glacial maximum. These results imply that the fluctuating water levels in pluvial Lake Lahontan had a minimal effect on shaping the genetic architecture of R. egregius. Coalescent analyses using the immigration with migration model show that contemporary gene flow between eastern and western Lahontan Basin populations does not occur. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 163–176.
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Phylogenetic relationships of the western North American cyprinid genus Richardsonius, with an overview of phylogeographic structure.
Molecular phylogenetics and evolution, 2009Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Abstract Diversification of many North American taxa, including freshwater fishes, has been heavily influenced by the effects of complex geological and climatic events throughout the Cenozoic that have significantly altered the landscape. Here, we employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys . We also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within the group. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and Richardsonius , with Clinostomus being sister to an Iotichthys – Richardsonius clade, hence the currently recognized sister relationship between Clinostomus and Richardsonius is not supported. These genera appear to be monophyletic lineages, and sister species within genera appear to be reciprocally monophyletic. The two species within the genus Richardsonius both exhibit phylogeographic structure that is worthy of further investigation. Divergence time estimates between genera and species are Miocene or Pliocene in age, and divergence between phylogroups within species occurred in the late Pliocene to Pleistocene. These splits coincide with documented geological and climatic events.
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Geographic Variation in Somatic Growth of Redside Shiner
Transactions of the American Fisheries Society, 2006Co-Authors: Derek D. Houston, Mark C. BelkAbstract:Abstract The geographic variation in growth rate and resulting body size is poorly known for most fish species. In this paper, we used data derived from otoliths to describe patterns of growth in redside shiners Richardsonius balteatus from seven native populations across the southern portion of its range, and we compare growth with latitude, elevation, and growing season to determine which of these environmental factors best predicts the growth patterns among these populations. To determine whether observed differences in growth resulted from environmental or genetic variation, we conducted a common-environment experiment on fish from three of the seven populations that showed contrasting patterns between latitude and length of growing season. Redside shiners exhibited about a 60% difference in size at age among populations in their natural environments. Growing season length was the best predictor of body size among these populations (Akaike weight = 0.78). In a common environment, temperature-specific ...
Dennis K. Shiozawa - One of the best experts on this subject based on the ideXlab platform.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus, a widely distributed western North American minnow
BMC Evolutionary Biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage. Results Genetic diversification in redside shiner began in the mid to late Pleistocene, but was not associated with LGM. Different clades of redside shiner were distributed in multiple glacial age refugia, and each clade retains a signature of population expansion, with clades having secondary contact in some areas. Conclusions Divergence times between redside shiner populations in the Bonneville Basin and the Upper Snake/Columbia River drainage precedes the Bonneville Flood, thus it is unlikely that redside shiner invaded the Bonneville Basin during this flooding event. All but one British Columbia population of redside shiner are associated with the Upper Columbia River drainage with the lone exception being a population near the coast, suggesting that the province as a whole was colonized from multiple refugia, but the inland British Columbia redside shiner populations are affiliated with a refugium in the Upper Columbia River drainage.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus , a widely distributed western North American minnow
BMC evolutionary biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage.
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The roles of Neogene geology and late Pleistocene lake levels in shaping the genetic structure of the Lahontan redside shiner Richardsonius egregius (Teleostei: Cyprinidae)
Biological Journal of the Linnean Society, 2011Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Shifting drainage patterns in western North America, shaped by geological activity and changing global climates, have influenced the evolution of many aquatic taxa. We investigated the role of late Pleistocene high stands in pluvial Lake Lahontan on the genetic structure of Richardsonius egregius, a minnow endemic to the Lahontan Basin of the western Great Basin. We used the mitochondrial cytochrome b gene to generate a phylogeny and assess intraspecific genetic diversity, to estimate divergence times between clades, and to evaluate whether gene flow currently occurs. The results obtained show that R. egregius exhibits genetic divergence between eastern and western Lahontan Basin populations. Divergence time estimates show that intraspecific genetic diversification began in the Pliocene or early Pleistocene, before the pluvial lake high stands associated with the last glacial maximum. These results imply that the fluctuating water levels in pluvial Lake Lahontan had a minimal effect on shaping the genetic architecture of R. egregius. Coalescent analyses using the immigration with migration model show that contemporary gene flow between eastern and western Lahontan Basin populations does not occur. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 163–176.
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Phylogenetic relationships of the western North American cyprinid genus Richardsonius, with an overview of phylogeographic structure.
Molecular phylogenetics and evolution, 2009Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brett R. RiddleAbstract:Abstract Diversification of many North American taxa, including freshwater fishes, has been heavily influenced by the effects of complex geological and climatic events throughout the Cenozoic that have significantly altered the landscape. Here, we employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys . We also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within the group. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and Richardsonius , with Clinostomus being sister to an Iotichthys – Richardsonius clade, hence the currently recognized sister relationship between Clinostomus and Richardsonius is not supported. These genera appear to be monophyletic lineages, and sister species within genera appear to be reciprocally monophyletic. The two species within the genus Richardsonius both exhibit phylogeographic structure that is worthy of further investigation. Divergence time estimates between genera and species are Miocene or Pliocene in age, and divergence between phylogroups within species occurred in the late Pliocene to Pleistocene. These splits coincide with documented geological and climatic events.
Gordon H. Reeves - One of the best experts on this subject based on the ideXlab platform.
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Redside shiner (Richardsonius balteatus) shoals provide a behavioral competitive refuge for subordinate juvenile steelhead trout (Oncorhynchus mykiss)
Canadian Journal of Fisheries and Aquatic Sciences, 2001Co-Authors: Craig A. Tinus, Gordon H. ReevesAbstract:We examined the relative effects of zero, three, and nine redside shiner (Richardsonius balteatus) on the aggression-related damage among three juvenile steelhead (Oncorhynchus mykiss) in aquaria at 15 and 20°C. No steelhead died when in the presence of nine redside shiner. When redside shiner were not present, mortality among the smallest steelhead was 80%. Thus, the survival of smaller juvenile steelhead was significantly enhanced by the presence of redside shiner. A second experiment was conducted in 6800-L stream channels at 15°C with natural substrate. In separate trials, 10 and 7 steelhead were held either alone or with 20 redside shiner. In the absence of redside shiner, fin damage was significantly greater among smaller steelhead. In both experiments, if a redside shiner group was present, the smallest steelhead frequently took refuge within the shiner group, thereby avoiding attack by dominant steelhead. We have termed this phenomenon a behavioural competitive refuge.
Brian Tilston Smith - One of the best experts on this subject based on the ideXlab platform.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus, a widely distributed western North American minnow
BMC Evolutionary Biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage. Results Genetic diversification in redside shiner began in the mid to late Pleistocene, but was not associated with LGM. Different clades of redside shiner were distributed in multiple glacial age refugia, and each clade retains a signature of population expansion, with clades having secondary contact in some areas. Conclusions Divergence times between redside shiner populations in the Bonneville Basin and the Upper Snake/Columbia River drainage precedes the Bonneville Flood, thus it is unlikely that redside shiner invaded the Bonneville Basin during this flooding event. All but one British Columbia population of redside shiner are associated with the Upper Columbia River drainage with the lone exception being a population near the coast, suggesting that the province as a whole was colonized from multiple refugia, but the inland British Columbia redside shiner populations are affiliated with a refugium in the Upper Columbia River drainage.
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Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus , a widely distributed western North American minnow
BMC evolutionary biology, 2014Co-Authors: Derek D. Houston, Dennis K. Shiozawa, Brian Tilston Smith, Brett R. RiddleAbstract:Background Biogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage.
