The Experts below are selected from a list of 9498 Experts worldwide ranked by ideXlab platform
Sandrine Plénet - One of the best experts on this subject based on the ideXlab platform.
-
Within- and among-population impact of Genetic Erosion on adult fitness-related traits in the European tree frog Hyla arborea
Heredity, 2013Co-Authors: Emilien Luquet, Jean-paul Lena, Pierre Joly, Thierry Lengagne, P. David, Jérôme Prunier, N. Perrin, Sandrine PlénetAbstract:Assessing in wild populations how fitness is impacted by inbreeding and Genetic drift is a major goal for conservation biology. An approach to measure the detrimental effects of inbreeding on fitness is to estimate correlations between molecular variation and phenotypic performances within and among populations. Our study investigated the effect of individual multilocus heterozygosity on body size, body condition and reproductive investment of males (that is, chorus attendance) and females (that is, clutch mass and egg size) in both small fragmented and large non-fragmented populations of European tree frog (Hyla arborea). Because adult size and/or condition and reproductive investment are usually related, Genetic Erosion may have detrimental effects directly on reproductive investment, and also on individual body size and condition that in turn may affect reproductive investment. We confirmed that the reproductive investment was highly size-dependent for both sexes. Larger females invested more in offspring production, and larger males attended the chorus in the pond more often. Our results did not provide evidence for a decline in body size, condition and reproductive effort with decreased multilocus heterozygosity both within and among populations. We showed that the lack of heterozygosity-fitness correlations within populations probably resulted from low inbreeding levels (inferior to ca. 20% full-sib mating rate), even in the small fragmented populations. The detrimental effects of fixation load were either low in adults or hidden by environmental variation among populations. These findings will be useful to design specific management actions to improve population persistence.
-
Genetic Erosion in wild populations makes resistance to a pathogen more costly
Evolution, 2012Co-Authors: Emilien Luquet, Jean-paul Lena, Pierre Joly, Thierry Lengagne, Trenton W. J. Garner, Christophe Bruel, Odile Grolet, Sandrine PlénetAbstract:Populations that have suffered from Genetic Erosion are expected to exhibit reduced average trait values or decreased variation in adaptive traits when experiencing periodic or emergent stressors such as infectious disease. Genetic Erosion may consequentially modify the ability of a potential host population to cope with infectious disease emergence. We experimentally investigate this relationship between Genetic variability and host response to exposure to an infectious agent both in terms of susceptibility to infection and indirect parasite-mediated responses that also impact fitness. We hypothesized that the deleterious consequences of exposure to the pathogen (Batrachochytrium dendrobatidis) would be more severe for tadpoles descended from European treefrog (Hyla arborea) populations lacking Genetic variability. Although all exposed tadpoles lacked detectable infection, we detected this relationship for some indirect host responses, predominantly in Genetically depleted animals, as well as an interaction between Genetic variability and pathogen dose on life span during the postmetamorphic period. Lack of infection and a decreased mass and postmetamorphic life span in low Genetic diversity tadpoles lead us to conclude that Genetic Erosion, while not affecting the ability to mount effective resistance strategies, also erodes the capacity to invest in resistance, increased tadpole growth rate, and metamorphosis relatively simultaneously.
-
Consequences of Genetic Erosion on fitness and phenotypic plasticity in European tree frog populations (Hyla arborea)
Journal of Evolutionary Biology, 2011Co-Authors: Emilien Luquet, Jean-paul Lena, Patrice David, Pierre Joly, Thierry Lengagne, Nicolas Perrin, Sandrine PlénetAbstract:The detrimental effects of Genetic Erosion on small isolated populations are widely recognized contrary to their interactions with environmental changes. The ability of genotypes to plastically respond to variability is probably essential for the persistence of these populations. Genetic Erosion impact may be exacerbated if inbreeding affects plastic responses or if their maintenance were at higher phenotypic costs. To understand the interplay 'Genetic Erosion-fitness-phenotypic plasticity', we experimentally compared, in different environments, the larval performances and plastic responses to predation of European tree frogs (Hyla arborea) from isolated and connected populations. Tadpoles from isolated populations were less performant, but the traits affected were environmental dependant. Heterosis observed in crosses between isolated populations allowed attributing their low fitness to inbreeding. Phenotypic plasticity can be maintained in the face of Genetic Erosion as inducible defences in response to predator were identical in all populations. However, the higher survival and developmental costs for isolated populations in harsh conditions may lead to an additional fitness loss for isolated populations.
Emilien Luquet - One of the best experts on this subject based on the ideXlab platform.
-
Within- and among-population impact of Genetic Erosion on adult fitness-related traits in the European tree frog Hyla arborea
Heredity, 2013Co-Authors: Emilien Luquet, Jean-paul Lena, Pierre Joly, Thierry Lengagne, P. David, Jérôme Prunier, N. Perrin, Sandrine PlénetAbstract:Assessing in wild populations how fitness is impacted by inbreeding and Genetic drift is a major goal for conservation biology. An approach to measure the detrimental effects of inbreeding on fitness is to estimate correlations between molecular variation and phenotypic performances within and among populations. Our study investigated the effect of individual multilocus heterozygosity on body size, body condition and reproductive investment of males (that is, chorus attendance) and females (that is, clutch mass and egg size) in both small fragmented and large non-fragmented populations of European tree frog (Hyla arborea). Because adult size and/or condition and reproductive investment are usually related, Genetic Erosion may have detrimental effects directly on reproductive investment, and also on individual body size and condition that in turn may affect reproductive investment. We confirmed that the reproductive investment was highly size-dependent for both sexes. Larger females invested more in offspring production, and larger males attended the chorus in the pond more often. Our results did not provide evidence for a decline in body size, condition and reproductive effort with decreased multilocus heterozygosity both within and among populations. We showed that the lack of heterozygosity-fitness correlations within populations probably resulted from low inbreeding levels (inferior to ca. 20% full-sib mating rate), even in the small fragmented populations. The detrimental effects of fixation load were either low in adults or hidden by environmental variation among populations. These findings will be useful to design specific management actions to improve population persistence.
-
Genetic Erosion in wild populations makes resistance to a pathogen more costly
Evolution, 2012Co-Authors: Emilien Luquet, Jean-paul Lena, Pierre Joly, Thierry Lengagne, Trenton W. J. Garner, Christophe Bruel, Odile Grolet, Sandrine PlénetAbstract:Populations that have suffered from Genetic Erosion are expected to exhibit reduced average trait values or decreased variation in adaptive traits when experiencing periodic or emergent stressors such as infectious disease. Genetic Erosion may consequentially modify the ability of a potential host population to cope with infectious disease emergence. We experimentally investigate this relationship between Genetic variability and host response to exposure to an infectious agent both in terms of susceptibility to infection and indirect parasite-mediated responses that also impact fitness. We hypothesized that the deleterious consequences of exposure to the pathogen (Batrachochytrium dendrobatidis) would be more severe for tadpoles descended from European treefrog (Hyla arborea) populations lacking Genetic variability. Although all exposed tadpoles lacked detectable infection, we detected this relationship for some indirect host responses, predominantly in Genetically depleted animals, as well as an interaction between Genetic variability and pathogen dose on life span during the postmetamorphic period. Lack of infection and a decreased mass and postmetamorphic life span in low Genetic diversity tadpoles lead us to conclude that Genetic Erosion, while not affecting the ability to mount effective resistance strategies, also erodes the capacity to invest in resistance, increased tadpole growth rate, and metamorphosis relatively simultaneously.
-
Consequences of Genetic Erosion on fitness and phenotypic plasticity in European tree frog populations (Hyla arborea)
Journal of Evolutionary Biology, 2011Co-Authors: Emilien Luquet, Jean-paul Lena, Patrice David, Pierre Joly, Thierry Lengagne, Nicolas Perrin, Sandrine PlénetAbstract:The detrimental effects of Genetic Erosion on small isolated populations are widely recognized contrary to their interactions with environmental changes. The ability of genotypes to plastically respond to variability is probably essential for the persistence of these populations. Genetic Erosion impact may be exacerbated if inbreeding affects plastic responses or if their maintenance were at higher phenotypic costs. To understand the interplay 'Genetic Erosion-fitness-phenotypic plasticity', we experimentally compared, in different environments, the larval performances and plastic responses to predation of European tree frogs (Hyla arborea) from isolated and connected populations. Tadpoles from isolated populations were less performant, but the traits affected were environmental dependant. Heterosis observed in crosses between isolated populations allowed attributing their low fitness to inbreeding. Phenotypic plasticity can be maintained in the face of Genetic Erosion as inducible defences in response to predator were identical in all populations. However, the higher survival and developmental costs for isolated populations in harsh conditions may lead to an additional fitness loss for isolated populations.
Mark J. Kennard - One of the best experts on this subject based on the ideXlab platform.
-
monitoring age related trends in genomic diversity of australian lungfish
Molecular Ecology, 2018Co-Authors: Daniel J. Schmidt, David T. Roberts, Steven Brooks, Peter K. Kind, Stewart Fallon, Andrew Mcdougall, Thomas Espinoza, Nick R. Bond, Mark J. KennardAbstract:An important challenge for conservation science is to detect declines in intraspecific diversity so that management action can be guided towards populations or species at risk. The lifespan of Australian lungfish (Neoceratodus forsteri) exceeds 80 years, and human impacts on breeding habitat over the last half century may have impeded recruitment, leaving populations dominated by old postreproductive individuals, potentially resulting in a small and declining breeding population. Here, we conduct a “single-sample” evaluation of Genetic Erosion within contemporary populations of the Australian lungfish. Genetic Erosion is a temporal decline in intraspecific diversity due to factors such as reduced population size and inbreeding. We examined whether young individuals showed signs of reduced Genetic diversity and/or inbreeding using a novel bomb radiocarbon dating method to age lungfish nonlethally, based on 14C ratios of scales. A total of 15,201 single nucleotide polymorphic (SNP) loci were genotyped in 92 individuals ranging in age from 2 to 77 years old. Standardized individual heterozygosity and individual inbreeding coefficients varied widely within and between riverine populations, but neither was associated with age, so perceived problems with recruitment have not translated into Genetic Erosion that could be considered a proximate threat to lungfish populations. Conservation concern has surrounded Australian lungfish for over a century. However, our results suggest that long-lived threatened species can maintain stable levels of intraspecific variability when sufficient reproductive opportunities exist over the course of a long lifespan. © 2018 John Wiley & Sons Ltd
Christian Wehenkel - One of the best experts on this subject based on the ideXlab platform.
-
ruling out Genetic Erosion in picea chihuahuana martinez
New Forests, 2017Co-Authors: Carmen Zulema Quinonesperez, Maria Socorro Gonzalezelizondo, Christian WehenkelAbstract:Genetic Erosion has been variously defined as the loss of particular alleles, the reduction in richness of the total number of alleles, and the reduction in evenness of the frequencies of alleles in a given place within populations or across species. Picea chihuahuana Martinez is an endangered endemic species known to occur in at least 40 locations along the Sierra Madre Occidental, in the states of Durango and Chihuahua (Mexico), but covering a total area of no more than 300 ha. The total number of individuals has been estimated to be around 42,600, and the number of mature individuals may be <2500. The populations (including mature trees, saplings and seedlings) vary in size from 21 to 5546 individuals. It has been suggested that small populations may be more susceptible to loss of Genetic variability via Genetic Erosion caused by Genetic drift, endogamy depression and strong unidirectional selection. The predicted reduction and eventual disappearance of a suitable habitat for P. chihuahuana due to climatic change imposes an additional risk of extinction. The principal aim of this study was therefore to estimate Genetic Erosion in 14 populations of P. chihuahuana Martinez by comparing Genetic diversity across diameter at breast height classes (as a proxy for age classes) by using AFLP markers and four indices of Genetic diversity that are commonly applied in combination with dominant Genetic markers. No evidence of Genetic Erosion was found in the 14 P. chihuahuana populations analyzed.
-
estimating Genetic Erosion in threatened conifers the example of picea chihuahuana martinez
2016Co-Authors: Christian Wehenkel, Cuauhtemoc Saenzromero, Juan P JaramillocorreaAbstract:The necessity of Genetic diversity for evolution and the relationship between heterozygosity and population fitness are important arguments for conserving Genetic diversity. The loss of Genetic diversity can be detrimental to the short-term viability of individuals and populations, and to the evolutionary potential of populations and species. Genetic Erosion can be defined as the permanent reduction in richness or evenness of common local alleles or as the loss of combinations of alleles over time in a defined area. Various international and intergovernmental organizations and networks have therefore recognized the need to assess and monitor plant Genetic Erosion in order to prevent such effects. The rare tree species Chihuahua spruce (Picea chihuahuana Martinez), which is endemic to Mexico, is an excellent model for estimating Genetic Erosion. The species occurs in about 40 isolated relict populations in the Sierra Madre Occidental, in the northwest of the country. Here, we will review a study assessing the degree of Genetic Erosion that was evaluated in five populations of P. chihuahuana M. in the State of Durango (Mexico), by comparing Genetic diversity across diameter classes (which were assumed to be a surrogate for age classes). In the two largest populations, there was a moderate loss of Genetic diversity at AFLP loci from older trees to saplings, and to young seedlings. Significant Genetic Erosion was only detected in the very small population of San Jose de las Causas (SJ). Hence, if Genetic diversity at AFLP loci reflects diversity in the whole genome, Genetic Erosion per se does not explain the relict status of Chihuahua spruce, except for very small populations, such as SJ. However, further researches with candidate genes are necessary to assess the putative loss of evolutionary potential in these stands. Activities that increase population size should be helpful to preserve Genetic diversity.
-
estimating Genetic Erosion using the example of picea chihuahuana martinez
Tree Genetics & Genomes, 2012Co-Authors: Christian Wehenkel, Cuauhtemoc SaenzromeroAbstract:Genetic Erosion can be defined as a permanent reduction in richness or evenness of common local alleles or the loss of combination of alleles over time in a defined area. This process can be detrimental to the short-term viability of individuals and populations, the evolutionary potential of populations and species, and the direct use of Genetic resources. Various international and intergovernmental organizations and networks have therefore recognized the need to assess and monitor plant Genetic Erosion in order to prevent such effects. The rare tree species Picea chihuahuana Martinez, which is endemic to Mexico, is an excellent model for estimating potential Genetic Erosion. The species occurs in about 40 often isolated relict populations in the Sierra Madre Occidental. In this study, the degree of Genetic Erosion was evaluated in five populations of P. chihuahuana M. in the State of Durango (Mexico), by comparing the Genetic diversity in diameter classes (as a surrogate variable for age classes). The results of the study demonstrate a moderate loss of Genetic diversity at some amplified fragment length polymorphism (AFLP) loci from the older trees to saplings and to young seedlings in the two largest populations. Significant Genetic Erosion was only detected in a very small population, named San Jose de las Causas (SJ). Hence, if Genetic diversity at AFLP loci reflects diversity in the genome on the whole, Genetic Erosion per se does not explain the relict status of Chihuahua spruce, except in very small populations, such as SJ, which comprised of ca. 120 individuals.
Nick R. Bond - One of the best experts on this subject based on the ideXlab platform.
-
monitoring age related trends in genomic diversity of australian lungfish
Molecular Ecology, 2018Co-Authors: Daniel J. Schmidt, David T. Roberts, Steven Brooks, Peter K. Kind, Stewart Fallon, Andrew Mcdougall, Thomas Espinoza, Nick R. Bond, Mark J. KennardAbstract:An important challenge for conservation science is to detect declines in intraspecific diversity so that management action can be guided towards populations or species at risk. The lifespan of Australian lungfish (Neoceratodus forsteri) exceeds 80 years, and human impacts on breeding habitat over the last half century may have impeded recruitment, leaving populations dominated by old postreproductive individuals, potentially resulting in a small and declining breeding population. Here, we conduct a “single-sample” evaluation of Genetic Erosion within contemporary populations of the Australian lungfish. Genetic Erosion is a temporal decline in intraspecific diversity due to factors such as reduced population size and inbreeding. We examined whether young individuals showed signs of reduced Genetic diversity and/or inbreeding using a novel bomb radiocarbon dating method to age lungfish nonlethally, based on 14C ratios of scales. A total of 15,201 single nucleotide polymorphic (SNP) loci were genotyped in 92 individuals ranging in age from 2 to 77 years old. Standardized individual heterozygosity and individual inbreeding coefficients varied widely within and between riverine populations, but neither was associated with age, so perceived problems with recruitment have not translated into Genetic Erosion that could be considered a proximate threat to lungfish populations. Conservation concern has surrounded Australian lungfish for over a century. However, our results suggest that long-lived threatened species can maintain stable levels of intraspecific variability when sufficient reproductive opportunities exist over the course of a long lifespan. © 2018 John Wiley & Sons Ltd