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Michael Wallis - One of the best experts on this subject based on the ideXlab platform.
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mammalian genome projects reveal new growth hormone gh sequences characterization of the gh encoding genes of armadillo dasypus novemcinctus hedgehog erinaceus europaeus Bat myotis lucifugus hyrax procavia capensis shrew sorex araneus ground squirrel
General and Comparative Endocrinology, 2008Co-Authors: Michael WallisAbstract:Abstract Mammalian growth hormone (GH) sequences have been shown previously to display episodic evolution: the sequence is generally strongly conserved but on at least two occasions during mammalian evolution (on lineages leading to higher primates and ruminants) bursts of rapid evolution occurred. However, the number of mammalian orders studied previously has been relatively limited, and the availability of sequence data via mammalian genome projects provides the potential for extending the range of GH gene sequences examined. Complete or nearly complete GH gene sequences for six mammalian species for which no data were previously available have been extracted from the genome databases— Dasypus novemcinctus (nine-banded armadillo), Erinaceus europaeus (western European hedgehog), Myotis lucifugus (Little Brown Bat), Procavia capensis (cape rock hyrax), Sorex araneus (European shrew), Spermophilus tridecemlineatus (13-lined ground squirrel). In addition incomplete data for several other species have been extended. Examination of the data in detail and comparison with previously available sequences has allowed assessment of the reliability of deduced sequences. Several of the new sequences differ substantially from the consensus sequence previously determined for eutherian GHs, indicating greater variability than previously recognised, and confirming the episodic pattern of evolution. The episodic pattern is not seen for signal sequences, 5′ upstream sequence or synonymous substitutions—it is specific to the mature protein sequence, suggesting that it relates to the hormonal function. The substitutions accumulated during the course of GH evolution have occurred mainly on the side of the hormone facing away from the receptor, in a non-random fashion, and it is suggested that this may reflect interaction of the receptor–bound hormone with other proteins or small ligands.
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mammalian genome projects reveal new growth hormone gh sequences characterization of the gh encoding genes of armadillo dasypus novemcinctus hedgehog erinaceus europaeus Bat myotis lucifugus hyrax procavia capensis shrew sorex araneus ground squirrel
General and Comparative Endocrinology, 2008Co-Authors: Michael WallisAbstract:Mammalian growth hormone (GH) sequences have been shown previously to display episodic evolution: the sequence is generally strongly conserved but on at least two occasions during mammalian evolution (on lineages leading to higher primates and ruminants) bursts of rapid evolution occurred. However, the number of mammalian orders studied previously has been relatively limited, and the availability of sequence data via mammalian genome projects provides the potential for extending the range of GH gene sequences examined. Complete or nearly complete GH gene sequences for six mammalian species for which no data were previously available have been extracted from the genome databases-Dasypus novemcinctus (nine-banded armadillo), Erinaceus europaeus (western European hedgehog), Myotis lucifugus (Little Brown Bat), Procavia capensis (cape rock hyrax), Sorex araneus (European shrew), Spermophilus tridecemlineatus (13-lined ground squirrel). In addition incomplete data for several other species have been extended. Examination of the data in detail and comparison with previously available sequences has allowed assessment of the reliability of deduced sequences. Several of the new sequences differ substantially from the consensus sequence previously determined for eutherian GHs, indicating greater variability than previously recognised, and confirming the episodic pattern of evolution. The episodic pattern is not seen for signal sequences, 5' upstream sequence or synonymous substitutions-it is specific to the mature protein sequence, suggesting that it relates to the hormonal function. The substitutions accumulated during the course of GH evolution have occurred mainly on the side of the hormone facing away from the receptor, in a non-random fashion, and it is suggested that this may reflect interaction of the receptor-bound hormone with other proteins or small ligands.
Hugh G. Broders - One of the best experts on this subject based on the ideXlab platform.
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population genetic structure within and among seasonal site types in the Little Brown Bat myotis lucifugus and the northern long eared Bat m septentrionalis
PLOS ONE, 2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:During late summer and early autumn, temperate Bats migrate from their summering sites to swarming sites, where mating likely occurs. However, the extent to which individuals of a single summering site migrate to the same swarming site, and vice versa, is not known. We examined the migratory connectivity between summering and swarming sites in two temperate, North American, Bat species, the Little Brown Bat (Myotis lucifugus) and the northern long-eared Bat (Myotis septentrionalis). Using mitochondrial and microsatellite DNA markers, we examined population structuring within and among summering and swarming sites. Both species exhibited moderate degrees of mitochondrial DNA differentiation (Little Brown Bat: FST(SWARMING)= 0.093, FST(SWARMING)= 0.052; northern long-eared Bat: FST(SWARMING)= 0.117, FST(SWARMING)= 0.043) and Little microsatellite DNA differentiation among summering and among swarming sites. Haplotype diversity was significantly higher at swarming sites than summering sites, supporting the idea that swarming sites are comprised of individuals from various summering sites. Further, pairwise analyses suggest that swarming sites are not necessarily comprised of only individuals from the most proximal summering colonies.
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effect of oceanic straits on gene flow in the recently endangered Little Brown Bat myotis lucifugus in maritime canada implications for the spread of white nose syndrome
Canadian Journal of Zoology, 2015Co-Authors: Lynne E Burns, Timothy R. Frasier, B A Mcleod, Hugh G. BrodersAbstract:White-nose syndrome is rapidly spreading in eastern North America, causing mass mortality of hibernating Bats. We characterized levels of genetic diversity and population structure of the Little Brown Bat (Myotis lucifugus (Le Conte, 1831)) in eastern Canada to infer the extent to which oceanic straits may be barriers to movement. To quantify metrics of gene flow and infer movement dynamics, we genotyped 679 M. lucifugus at nine nuclear microsatellites (nDNA) and sequenced a portion of the mitochondrial DNA (mtDNA). We found high levels of genetic diversity and Little population structure, with ≈13-fold higher differentiation of mtDNA than nDNA markers, suggesting that structuring patterns largely result from female philopatry. Discriminant analysis of principle components suggested that the subtle underlying structure was not concordant with sampling site. Regional differentiation (FST, Dest, Mantel test residuals) is mostly consistent with genetic isolation by distance. However, samples from Newfoundlan...
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mercury in Little Brown Bat myotis lucifugus maternity colonies and its correlation with freshwater acidity in nova scotia canada
Environmental Science & Technology, 2015Co-Authors: Megan E Little, Hugh G. Broders, Neil M Burgess, Linda M CampbellAbstract:Insectivorous Little Brown Bats are exposed to elevated concentrations of mercury (Hg) through their preference for aquatic-based prey. Here we investigated spatial patterns of total Hg (THg) in fur from 10 Little Brown Bat maternity colonies across Nova Scotia, and assessed relationships with the acidity of nearby lakes and rivers. Total Hg concentrations were measured in fur samples from 149 adult female Little Brown Bats. Values showed significant variation among colonies (mean range 3.76–27.38 μg/g, dry weight), and 48% of individuals had Hg concentrations in excess of the 10 μg/g threshold associated with neurochemical changes in Chiroptera conspecifics (n = 26) from Virginia. Average surface water acidity parameters (pH and acid neutralization capacity) within an 8 km radius of each maternity roost showed strong negative associations with average colony fur THg concentrations. This suggests that freshwater acidity in foraging grounds explains much of the variation in average fur THg concentrations i...
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Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) inference of population structure.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat and northern long-eared Bat scatterplots of genetically distinct clusters identified through DAPC within adegenet. Also shown are the corresponding BIC plots for various numbers of clusters (above right) and the DA eigenvalues for the displayed scatterplots (below right).
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Map of the Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) swarming (circles) and summering (squares) sites.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat summering sites are represented by black squares and white squares represent northern long-eared summering sites. Both species were sampled from all swarming sites excluding Vault Cave (Site 9). Tissue samples were collected between 1999–2012 across Quebec, New Brunswick and Nova Scotia, Canada.
Timothy R. Frasier - One of the best experts on this subject based on the ideXlab platform.
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population genetic structure within and among seasonal site types in the Little Brown Bat myotis lucifugus and the northern long eared Bat m septentrionalis
PLOS ONE, 2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:During late summer and early autumn, temperate Bats migrate from their summering sites to swarming sites, where mating likely occurs. However, the extent to which individuals of a single summering site migrate to the same swarming site, and vice versa, is not known. We examined the migratory connectivity between summering and swarming sites in two temperate, North American, Bat species, the Little Brown Bat (Myotis lucifugus) and the northern long-eared Bat (Myotis septentrionalis). Using mitochondrial and microsatellite DNA markers, we examined population structuring within and among summering and swarming sites. Both species exhibited moderate degrees of mitochondrial DNA differentiation (Little Brown Bat: FST(SWARMING)= 0.093, FST(SWARMING)= 0.052; northern long-eared Bat: FST(SWARMING)= 0.117, FST(SWARMING)= 0.043) and Little microsatellite DNA differentiation among summering and among swarming sites. Haplotype diversity was significantly higher at swarming sites than summering sites, supporting the idea that swarming sites are comprised of individuals from various summering sites. Further, pairwise analyses suggest that swarming sites are not necessarily comprised of only individuals from the most proximal summering colonies.
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effect of oceanic straits on gene flow in the recently endangered Little Brown Bat myotis lucifugus in maritime canada implications for the spread of white nose syndrome
Canadian Journal of Zoology, 2015Co-Authors: Lynne E Burns, Timothy R. Frasier, B A Mcleod, Hugh G. BrodersAbstract:White-nose syndrome is rapidly spreading in eastern North America, causing mass mortality of hibernating Bats. We characterized levels of genetic diversity and population structure of the Little Brown Bat (Myotis lucifugus (Le Conte, 1831)) in eastern Canada to infer the extent to which oceanic straits may be barriers to movement. To quantify metrics of gene flow and infer movement dynamics, we genotyped 679 M. lucifugus at nine nuclear microsatellites (nDNA) and sequenced a portion of the mitochondrial DNA (mtDNA). We found high levels of genetic diversity and Little population structure, with ≈13-fold higher differentiation of mtDNA than nDNA markers, suggesting that structuring patterns largely result from female philopatry. Discriminant analysis of principle components suggested that the subtle underlying structure was not concordant with sampling site. Regional differentiation (FST, Dest, Mantel test residuals) is mostly consistent with genetic isolation by distance. However, samples from Newfoundlan...
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Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) inference of population structure.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat and northern long-eared Bat scatterplots of genetically distinct clusters identified through DAPC within adegenet. Also shown are the corresponding BIC plots for various numbers of clusters (above right) and the DA eigenvalues for the displayed scatterplots (below right).
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Map of the Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) swarming (circles) and summering (squares) sites.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat summering sites are represented by black squares and white squares represent northern long-eared summering sites. Both species were sampled from all swarming sites excluding Vault Cave (Site 9). Tissue samples were collected between 1999–2012 across Quebec, New Brunswick and Nova Scotia, Canada.
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AMOVA results for the partitioning of mtDNA of Little Brown Bat (M. lucifugus) and northern long-eared Bat (M. septentrionalis) variation across sample site types in eastern Canada and nDNA global FST across sample site types, as well as all sites.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:AMOVA results for the partitioning of mtDNA of Little Brown Bat (M. lucifugus) and northern long-eared Bat (M. septentrionalis) variation across sample site types in eastern Canada and nDNA global FST across sample site types, as well as all sites.
Lynne E Burns - One of the best experts on this subject based on the ideXlab platform.
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population genetic structure within and among seasonal site types in the Little Brown Bat myotis lucifugus and the northern long eared Bat m septentrionalis
PLOS ONE, 2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:During late summer and early autumn, temperate Bats migrate from their summering sites to swarming sites, where mating likely occurs. However, the extent to which individuals of a single summering site migrate to the same swarming site, and vice versa, is not known. We examined the migratory connectivity between summering and swarming sites in two temperate, North American, Bat species, the Little Brown Bat (Myotis lucifugus) and the northern long-eared Bat (Myotis septentrionalis). Using mitochondrial and microsatellite DNA markers, we examined population structuring within and among summering and swarming sites. Both species exhibited moderate degrees of mitochondrial DNA differentiation (Little Brown Bat: FST(SWARMING)= 0.093, FST(SWARMING)= 0.052; northern long-eared Bat: FST(SWARMING)= 0.117, FST(SWARMING)= 0.043) and Little microsatellite DNA differentiation among summering and among swarming sites. Haplotype diversity was significantly higher at swarming sites than summering sites, supporting the idea that swarming sites are comprised of individuals from various summering sites. Further, pairwise analyses suggest that swarming sites are not necessarily comprised of only individuals from the most proximal summering colonies.
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effect of oceanic straits on gene flow in the recently endangered Little Brown Bat myotis lucifugus in maritime canada implications for the spread of white nose syndrome
Canadian Journal of Zoology, 2015Co-Authors: Lynne E Burns, Timothy R. Frasier, B A Mcleod, Hugh G. BrodersAbstract:White-nose syndrome is rapidly spreading in eastern North America, causing mass mortality of hibernating Bats. We characterized levels of genetic diversity and population structure of the Little Brown Bat (Myotis lucifugus (Le Conte, 1831)) in eastern Canada to infer the extent to which oceanic straits may be barriers to movement. To quantify metrics of gene flow and infer movement dynamics, we genotyped 679 M. lucifugus at nine nuclear microsatellites (nDNA) and sequenced a portion of the mitochondrial DNA (mtDNA). We found high levels of genetic diversity and Little population structure, with ≈13-fold higher differentiation of mtDNA than nDNA markers, suggesting that structuring patterns largely result from female philopatry. Discriminant analysis of principle components suggested that the subtle underlying structure was not concordant with sampling site. Regional differentiation (FST, Dest, Mantel test residuals) is mostly consistent with genetic isolation by distance. However, samples from Newfoundlan...
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Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) inference of population structure.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat and northern long-eared Bat scatterplots of genetically distinct clusters identified through DAPC within adegenet. Also shown are the corresponding BIC plots for various numbers of clusters (above right) and the DA eigenvalues for the displayed scatterplots (below right).
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Map of the Little Brown Bat (Myotis lucifugus) and northern long-eared Bat (M. septentrionalis) swarming (circles) and summering (squares) sites.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:Little Brown Bat summering sites are represented by black squares and white squares represent northern long-eared summering sites. Both species were sampled from all swarming sites excluding Vault Cave (Site 9). Tissue samples were collected between 1999–2012 across Quebec, New Brunswick and Nova Scotia, Canada.
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AMOVA results for the partitioning of mtDNA of Little Brown Bat (M. lucifugus) and northern long-eared Bat (M. septentrionalis) variation across sample site types in eastern Canada and nDNA global FST across sample site types, as well as all sites.
2015Co-Authors: Laura N. L. Johnson, Lynne E Burns, Timothy R. Frasier, Brenna A. Mcleod, Krista Arseneault, Hugh G. BrodersAbstract:AMOVA results for the partitioning of mtDNA of Little Brown Bat (M. lucifugus) and northern long-eared Bat (M. septentrionalis) variation across sample site types in eastern Canada and nDNA global FST across sample site types, as well as all sites.
Winifred F. Frick - One of the best experts on this subject based on the ideXlab platform.
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higher fat stores contribute to persistence of Little Brown Bat populations with white nose syndrome
Journal of Animal Ecology, 2019Co-Authors: Jonathan D Reichard, Marianne S Moore, Craig K R Willis, Tina L. Cheng, Winifred F. Frick, Alexander R Gerson, Joely G Desimone, Auston Marm KilpatrickAbstract:The persistence of populations declining from novel stressors depends, in part, on their ability to respond by trait change via evolution or plasticity. White-nose syndrome (WNS) has caused rapid declines in several North America Bat species by disrupting hibernation behaviour, leading to body fat depletion and starvation. However, some populations of Myotis lucifugus now persist with WNS by unknown mechanisms. We examined whether persistence of M. lucifigus with WNS could be explained by increased body fat in early winter, which would allow Bats to tolerate the increased energetic costs associated with WNS. We also investigated whether Bats were escaping infection or resistant to infection as an alternative mechanism explaining persistence. We measured body fat in early and late winter during initial WNS invasion and 8 years later at six sites where Bats are now persisting. We also measured infection prevalence and intensity in persisting populations. Infection prevalence was not significantly lower than observed in declining populations. However, at two sites, infection loads were lower than observed in declining populations. Body fat in early winter was significantly higher in four of the six persisting populations than during WNS invasion. Physiological models of energy use indicated that these higher fat stores could reduce WNS mortality by 58%-70%. These results suggest that differences in fat storage and infection dynamics have reduced the impacts of WNS in many populations. Increases in body fat provide a potential mechanism for management intervention to help conserve Bat populations.
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resistance in persisting Bat populations after white nose syndrome invasion
Philosophical Transactions of the Royal Society B, 2017Co-Authors: Kate E. Langwig, Jeffrey T. Foster, Winifred F. Frick, Joseph R Hoyt, Katy L Parise, Marm A KilpatrickAbstract:Increases in anthropogenic movement have led to a rise in pathogen introductions and the emergence of infectious diseases in naive host communities worldwide. We combined empirical data and mathematical models to examine changes in disease dynamics in Little Brown Bat ( Myotis lucifugus ) populations following the introduction of the emerging fungal pathogen Pseudogymnoascus destructans , which causes the disease white-nose syndrome. We found that infection intensity was much lower in persisting populations than in declining populations where the fungus has recently invaded. Fitted models indicate that this is most consistent with a reduction in the growth rate of the pathogen when fungal loads become high. The data are inconsistent with the evolution of tolerance or an overall reduced pathogen growth rate that might be caused by environmental factors. The existence of resistance in some persisting populations of Little Brown Bats offers a glimmer of hope that a precipitously declining species will persist in the face of this deadly pathogen. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’.
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conservation implications of ameliorating survival of Little Brown Bats with white nose syndrome
Ecological Applications, 2015Co-Authors: Brooke Maslo, Mick Valent, John F Gumbs, Winifred F. FrickAbstract:Management of wildlife populations impacted by novel threats is often challenged by a lack of data on temporal changes in demographic response. Populations may suffer rapid declines from the introduction of new stressors, but how demography changes over time is critical to determining long-term outcomes for populations. White-nose syndrome (WNS), an infectious disease of hibernating Bats, has caused massive and rapid population declines in several hibernating species of Bats in North America since the disease was first observed on the continent in 2006. Estimating annual survival rates and demographic trends among remnant colonies of hibernating Bats that experienced mass mortality from WNS is needed to determine long-term population viability of species impacted by this disease. Using mark-recapture data on infected Little Brown Bats (Myotis lucifugus), we estimated the first apparent annual survival rates for four years following WNS detection at a site. We found strong support for an increasing trend in annual survival, which improved from 0.68 (95% CI = 0.44-0.85) to 0.75 (95% CI = 0.51-0.89) for males and 0.65 (95% CI = 0.44-0.81) to 0.70 (95% CI = 0.50-0.84) for females. These results suggest that stabilization at remnant colonies after mass mortality from WNS may be due to improved survival and not from immigration from other areas. Despite ameliorating survival, our stochastic matrix projection model predicts continued declines for Little Brown Bat populations (λ = 0.95), raising concern for the regional persistence of this species. We conducted a vital rate sensitivity analysis and determined that adult and juvenile survival, as opposed to fecundity, are the demographic parameters most important to target to maximize recovery potential of Little Brown Bat populations in areas impacted by WNS.