Artigos de revistas: "Population and ecological genetics"

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Day, K. P., J. C. Koella, S. Nee, S. Gupta e A. F. Read. "Population genetics and dynamics ofPlasmodium falciparum: an ecological view". Parasitology 104, S1 (junho de 1992): S35—S52. http://dx.doi.org/10.1017/s0031182000075235.

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SUMMARYMolecular characterization of thePlasmodium falciparumgenome has led to identification of polymorphic loci and the mechanisms generating genetic diversity in this parasite. This information has resulted in the development of molecular methods to type parasite diversity in the field. Consequently, we are now in a position to describe the population genetics and dynamics ofP. falciparum. The limited number of field studies that have been conducted to date have revealed an extraordinary degree of genetic diversity in natural parasite populations. Heterozygous recombination which occurs during meiosis appears to be one mechanism for generating genetic diversity. The rate at which such recombination occurs in natural parasite populations defines the genetic structure of the parasite population and can influence the ability of the parasite to respond to selection pressure. The high frequency of single genotype infections and the female-biased gametocyte sex ratios found in hyperendemic malaria areas suggest that self-fertilization occurs frequently. Population- wide surveys of allele frequencies in endemic areas have, however, shown no evidence of linkage disequilibrium and are consistent with a panmictic population structure. We argue that these studies have only sampled symptomatic infections, within which rare or recombinant genotypes may be disproportionately represented. They also take no account of the spatial structure ofP. falciparumpopulations. Systematic investigations of the amount of heterozygosity in small areas as part of population-wide surveys are required to define the genetic structure ofP. falciparumpopulations. Population dynamic studies which consider genetic heterogeneity ofP. falciparumhave shown fluctuations of different serotypes in space and time. The host immune response appears to play an important role in generating these dynamics. Integrated field and laboratory studies, which consider the interaction between population genetics and dynamics, will be necessary to describe the population biology ofP. falciparum.

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Majewski, Jacek, e Frederick M. Cohan. "Adapt Globally, Act Locally: The Effect of Selective Sweeps on Bacterial Sequence Diversity". Genetics 152, n.º 4 (1 de agosto de 1999): 1459–74. http://dx.doi.org/10.1093/genetics/152.4.1459.

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Abstract Previous studies have shown that genetic exchange in bacteria is too rare to prevent neutral sequence divergence between ecological populations. That is, despite genetic exchange, each population should diverge into its own DNA sequence-similarity cluster. In those studies, each selective sweep was limited to acting within a single ecological population. Here we postulate the existence of globally adaptive mutations, which may confer a selective advantage to all ecological populations constituting a metapopulation. Such adaptations cause global selective sweeps, which purge the divergence both within and between populations. We found that the effect of recurrent global selective sweeps on neutral sequence divergence is highly dependent on the mechanism of genetic exchange. Global selective sweeps can prevent populations from reaching high levels of neutral sequence divergence, but they cannot cause two populations to become identical in neutral sequence characters. The model supports the earlier conclusion that each ecological population of bacteria should form its own distinct DNA sequence-similarity cluster.

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Bochkov, Nikolai P. "Human ecological genetics". Ecological genetics 1, n.º 1 (15 de janeiro de 2003): 16–21. http://dx.doi.org/10.17816/ecogen1016-21.

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A resumptive review of the three types of effects of new environmental factors on human heredity is presented: 1) alteration of hereditary elements (induced mutagenesis); 2) pathological manifestations of gene expression on the specific environmental factors (ecogenetic diseases, pharmacogenetics, toxicogenomics, nutrigenomics); 3) alteration of the population gene pool as a result of disturbance of genetic balance between mutation process and selection. The following thesis is proving: in spite of severity and seriousness of current problems of ecological human genetics, the decision can be made on the basis of fundamental sciences advances and technological progress.

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Gustafsson, L. "Avian genetics: A population and ecological approach". Trends in Ecology & Evolution 3, n.º 9 (setembro de 1988): 245–46. http://dx.doi.org/10.1016/0169-5347(88)90168-1.

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Cooper, Vaughn S., e Richard E. Lenski. "The population genetics of ecological specialization in evolving Escherichia coli populations". Nature 407, n.º 6805 (outubro de 2000): 736–39. http://dx.doi.org/10.1038/35037572.

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MUFWENE, S. S. "FROM GENETIC CREOLISTICS TO HISTORICAL DIALECTOLOGY: ECOLOGICAL AND POPULATION GENETICS PERSPECTIVES". American Speech 75, n.º 3 (1 de setembro de 2000): 262–65. http://dx.doi.org/10.1215/00031283-75-3-262.

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Sherwin, WB, e ND Murray. "Population and Conservation Genetics of Marsupials". Australian Journal of Zoology 37, n.º 3 (1989): 161. http://dx.doi.org/10.1071/zo9890161.

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This article summarises current knowledge of marsupial population genetics, and discusses its relevance to the conservation of marsupial species. It has been suggested that there is much lower genetic variation within marsupial populations than in eutherian mammals. This trend is not evident in the electrophoretic data summarised here. However, genetic differentiation between populations, subspecies, and species of marsupials appears to be slightly lower than comparable values for eutherians. Genetic estimates of migration between populations are scarce at present, but show values that are comparable with eutherians. Some studies of marsupial population genetics have used non-electrophoretic characteristics, or have addressed the possibility of selection on the characters analysed. Although few, these studies indicate the suitability of marsupials for such investigations. Recent debate over the theories and applications of conservation genetics has made it clear that more research is required on individual species. Given the record of extinction of marsupials in the last 200 years, it is important to test the applicability of these theories to individual marsupial species. Several examples are discussed emphasising the need for ecological studies that estimate the effective number of reproducing individuals per generation. This figure, called the effective size, is the corner- stone of conservation genetics theory, being an important determinant of both the rate of loss of variation between individuals, and the rate of inbreeding. The effective size of the mainland population of the eastern barred bandicoot, Perameles gunnii, appears to be only about one-tenth of its census number. This result is comparable with estimates made in other vertebrates, and demonstrates that many marsupial species which appear to have an adequate census size on ecological grounds may face genetic problems resulting from small effective size.

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Marinkovic, Dragoslav, e Vladimir Kekic. "Capacities for population-genetic variation and ecological adaptations". Genetika 39, n.º 2 (2007): 93–102. http://dx.doi.org/10.2298/gensr0702093m.

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In contemporary science of population genetics it is equally complex and important to visualize how adaptive limits of individual variation are determined, as well as to describe the amount and sort of this variation. Almost all century the scientists devoted their efforts to explain the principles and structure of biological variation (genetic, developmental, environmental, interactive, etc.), basing its maintenance within existing limits mostly on equilibria proclaimed by Hardy-Weinberg rules. Among numerous model-organisms that have been used to prove these rules and demonstrate new variants within mentioned concepts, Drosophila melanogaster is a kind of queen that is used in thousands of experiments for almost exactly 100 years (CARPENTER 1905), with which numerous discoveries and principles were determined that later turned out to be applicable to all other organisms. It is both, in nature and in laboratory, that Drosophilids were used to demonstrate the basic principles of population-genetic variation that was later applied to other species of animals. In ecological-genetic variation their richness in different environments could be used as an exact indicator of the status of a determined habitat, and its population-genetic structure may definitely point out to a possibility that specific resources of the environment start to be in danger to deteriorate, or to disappear in the near future. This paper shows clear-cut differences among environmental habitats, when populations of Drosophilidae are quantitatively observed in different wild, semi-domestic and domestic environments, demonstrating a highly expressed mutual dependence of these two parameters. A crucial approach is how to estimate the causes that determine the limits of biological, i.e. of individual and population-genetic variation. The realized, i.e. adaptive variation, is much lesser than a total possible variation of a polygenic trait, and in this study, using a moderately complex gene-enzyme system, is estimated to be smaller than 0.2%. For an allozymic system based on 9 loci at three D. melanogaster chromosomes, the estimate is that chromosomal types are reduced, on the average, to ca. 3% during meiotic divisions, and that available gene-enzyme combinations are reduced further 15 times in gamete selection. So finalized metabolic or adaptive developmental programs are emphasized to be the basic targets of Darwinian selection, rather than chromosomes or individual genes, that are involved in these programs.

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Easteal, Simon. "THE ECOLOGICAL GENETICS OF INTRODUCED POPULATIONS OF THE GIANT TOAD BUFO MARINUS. II. EFFECTIVE POPULATION SIZE". Genetics 110, n.º 1 (1 de maio de 1985): 107–22. http://dx.doi.org/10.1093/genetics/110.1.107.

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ABSTRACT The allele frequencies are described at ten polymorphic enzyme loci (of a total of 22 loci sampled) in 15 populations of the neotropical giant toad, Bufo marinus, introduced to Hawaii and Australia in the 1930s. The history of establishment of the ten populations is described and used as a framework for the analysis of allele frequency variances. The variances are used to determine the effective sizes of the populations. The estimates obtained (390 and 346) are reasonably precise, homogeneous between localities and much smaller than estimates of neighborhood size obtained previously using ecological methods. This discrepancy is discussed, and it is concluded that the estimates obtained here using genetic methods are the more reliable.

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Adams, Clare I. M., Michael Knapp, Neil J. Gemmell, Gert-Jan Jeunen, Michael Bunce, Miles D. Lamare e Helen R. Taylor. "Beyond Biodiversity: Can Environmental DNA (eDNA) Cut It as a Population Genetics Tool?" Genes 10, n.º 3 (1 de março de 2019): 192. http://dx.doi.org/10.3390/genes10030192.

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Population genetic data underpin many studies of behavioral, ecological, and evolutionary processes in wild populations and contribute to effective conservation management. However, collecting genetic samples can be challenging when working with endangered, invasive, or cryptic species. Environmental DNA (eDNA) offers a way to sample genetic material non-invasively without requiring visual observation. While eDNA has been trialed extensively as a biodiversity and biosecurity monitoring tool with a strong taxonomic focus, it has yet to be fully explored as a means for obtaining population genetic information. Here, we review current research that employs eDNA approaches for the study of populations. We outline challenges facing eDNA-based population genetic methodologies, and suggest avenues of research for future developments. We advocate that with further optimizations, this emergent field holds great potential as part of the population genetics toolkit.

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Farnum, Peter, Al Lucier e Richard Meilan. "Ecological and population genetics research imperatives for transgenic trees". Tree Genetics & Genomes 3, n.º 2 (16 de janeiro de 2007): 119–33. http://dx.doi.org/10.1007/s11295-006-0063-z.

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Fieiel, Chester R. "Crayfish population genetic studies: assessment and trends". Freshwater Crayfish 22, n.º 1 (31 de dezembro de 2016): 19–42. http://dx.doi.org/10.5869/fc.2016.v22-1.17.

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Abstract I surveyed the peer-reviewed literature for studies on crayfish population genetics over the last 20 years (1996 to 2015). My objectives were to determine if there is research disparities based on crayfish conservation status, ecological group, geographic location, and genetic methods used. Additionally, I wished to determine overall trends in crayfish genetics related to population variability, systematics, and technique development. An extensive literature search yielded 201 peer-reviewed articles with genetic information published on 335 of the 590 crayfish species found worldwide. The majority of peer-reviewed articles took place in Europe and Australia/Oceania despite the fact that crayfish biodiversity is greatest in North America. Crayfish within each ecological group (primary burrowers, lotic inhabitants, lentic inhabitants, and stygobitic species) are represented in these published papers. I found published articles on ~ 57% of the estimated 590 extant species. Further, of the 173 species listed as critically endangered, endangered, vulnerable, or as near threatened by the International Union for Conservation of Nature, I found published research on ~ 62% of these species in these classifications thus indicating a knowledge gap for many imperiled species. This lack of basic genetic (and ecological) information is significant as species designation is often used to determine where we should focus our conservation actions. Understanding what constitutes a single interbreeding population and identifying taxonomic designations are priorities for defining conservation management plans.

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Figiel, Chester R. "Crayfish population genetic studies: assessment and trends". Freshwater Crayfish 22, n.º 1 (31 de dezembro de 2016): 19–42. http://dx.doi.org/10.5869/fc.2016.v22-1.19.

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Abstract I surveyed the peer-reviewed literature for studies on crayfish population genetics over the last 20 years (1996 to 2015). My objectives were to determine if there is research disparities based on crayfish conservation status, ecological group, geographic location, and genetic methods used. Additionally, I wished to determine overall trends in crayfish genetics related to population variability, systematics, and technique development. An extensive literature search yielded 201 peer-reviewed articles with genetic information published on 335 of the 590 crayfish species found worldwide. The majority of peer-reviewed articles took place in Europe and Australia/Oceania despite the fact that crayfish biodiversity is greatest in North America. Crayfish within each ecological group (primary burrowers, lotic inhabitants, lentic inhabitants, and stygobitic species) are represented in these published papers. I found published articles on ~ 57% of the estimated 590 extant species. Further, of the 173 species listed as critically endangered, endangered, vulnerable, or as near threatened by the International Union for Conservation of Nature, I found published research on ~ 62% of these species in these classifications thus indicating a knowledge gap for many imperiled species. This lack of basic genetic (and ecological) information is significant as species designation is often used to determine where we should focus our conservation actions. Understanding what constitutes a single interbreeding population and identifying taxonomic designations are priorities for defining conservation management plans.

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Teixeira, João C., e Christian D. Huber. "The inflated significance of neutral genetic diversity in conservation genetics". Proceedings of the National Academy of Sciences 118, n.º 10 (19 de fevereiro de 2021): e2015096118. http://dx.doi.org/10.1073/pnas.2015096118.

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The current rate of species extinction is rapidly approaching unprecedented highs, and life on Earth presently faces a sixth mass extinction event driven by anthropogenic activity, climate change, and ecological collapse. The field of conservation genetics aims at preserving species by using their levels of genetic diversity, usually measured as neutral genome-wide diversity, as a barometer for evaluating population health and extinction risk. A fundamental assumption is that higher levels of genetic diversity lead to an increase in fitness and long-term survival of a species. Here, we argue against the perceived importance of neutral genetic diversity for the conservation of wild populations and species. We demonstrate that no simple general relationship exists between neutral genetic diversity and the risk of species extinction. Instead, a better understanding of the properties of functional genetic diversity, demographic history, and ecological relationships is necessary for developing and implementing effective conservation genetic strategies.

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Shapcott, A. "Genetic and Ecological Variation in Atherosperma moschatum and the Implications for Conservation of Its Biodiversity". Australian Journal of Botany 42, n.º 6 (1994): 663. http://dx.doi.org/10.1071/bt9940663.

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Population genetics and ecology of Atherosperma moschatum Labill. (sassafras), a major canopy tree of Australian temperate rainforests, were examined and used to identify priorities and strategies for conservation of its genetic diversity. The genetic diversity among populations was fairly low, but higher than average for long-lived late successional or wind dispersed species (Hamrick and Godt 1989). Genetic distances between populations were correlated with geographic distances and climatic differences. The major genetic differentiation was between the mainland populations and those in Tasmania, with the New South Wales populations being quite genetically distinct. Most genetic variation was found within populations, however, most populations were inbred. This is likely to be due to selfing and spatial genetic substructure resulting from vegetative spread and local dispersal. There was evidence of regeneration in all populations, however no consistent regeneration patterns emerged. Population density was inexplicably correlated with genetic distance. There was as much diversity in all variables (ecological and genetic) measured in small isolated populations as there was in stands within larger assemblages; therefore, population size does not appear to be a major factor affecting viability. Genetic variation was spread throughout the distribution of A. moschatum. Therefore, populations from throughout its range would need to be conserved to retain the genetic diversity within this species.

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Alphey, Nina, e Michael B. Bonsall. "Interplay of population genetics and dynamics in the genetic control of mosquitoes". Journal of The Royal Society Interface 11, n.º 93 (6 de abril de 2014): 20131071. http://dx.doi.org/10.1098/rsif.2013.1071.

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Some proposed genetics-based vector control methods aim to suppress or eliminate a mosquito population in a similar manner to the sterile insect technique. One approach under development in Anopheles mosquitoes uses homing endonuclease genes (HEGs)—selfish genetic elements (inherited at greater than Mendelian rate) that can spread rapidly through a population even if they reduce fitness. HEGs have potential to drive introduced traits through a population without large-scale sustained releases. The population genetics of HEG-based systems has been established using discrete-time mathematical models. However, several ecologically important aspects remain unexplored. We formulate a new continuous-time (overlapping generations) combined population dynamic and genetic model and apply it to a HEG that targets and knocks out a gene that is important for survival. We explore the effects of density dependence ranging from undercompensating to overcompensating larval competition, occurring before or after HEG fitness effects, and consider differences in competitive effect between genotypes (wild-type, heterozygotes and HEG homozygotes). We show that population outcomes—elimination, suppression or loss of the HEG—depend crucially on the interaction between these ecological aspects and genetics, and explain how the HEG fitness properties, the homing rate (drive) and the insect's life-history parameters influence those outcomes.

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Hoffmann, A. A., C. M. Sgrò e S. H. Lawler. "Ecological Population Genetics: The Interface Between Genes and the Environment". Annual Review of Genetics 29, n.º 1 (dezembro de 1995): 349–70. http://dx.doi.org/10.1146/annurev.ge.29.120195.002025.

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Rehfeldt, Gerald E., Laura P. Leites, Dennis G. Joyce e Aaron R. Weiskittel. "Role of population genetics in guiding ecological responses to climate". Global Change Biology 24, n.º 2 (25 de setembro de 2017): 858–68. http://dx.doi.org/10.1111/gcb.13883.

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Cheng, Changde, Bradley J. White, Colince Kamdem, Keithanne Mockaitis, Carlo Costantini, Matthew W. Hahn e Nora J. Besansky. "Ecological Genomics of Anopheles gambiae Along a Latitudinal Cline: A Population-Resequencing Approach". Genetics 190, n.º 4 (29 de dezembro de 2011): 1417–32. http://dx.doi.org/10.1534/genetics.111.137794.

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DAMGAARD, CHRISTIAN. "Evolution of advantageous alleles affecting population ecological characteristics in partially inbreeding populations". Hereditas 138, n.º 2 (junho de 2003): 122–28. http://dx.doi.org/10.1034/j.1601-5223.2003.01642.x.

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Alle, Benn R., Lupe Furtado-Alle, Cedric Gondro e João Carlos M. Magalhães. "Kuri: A Simulator of Ecological Genetics for Tree Populations". Journal of Artificial Evolution and Applications 2009 (26 de julho de 2009): 1–5. http://dx.doi.org/10.1155/2009/783647.

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This paper presents Kuri, a software package developed to simulate the temporal and spatial dynamics of genetic variability in populations and multispecies communities of trees, as well as their interactions with environmental factors. A conceptual model using agents inspired on Echo models is used to define the environment, the hierarchical structures, and the low-level rules of the system. At the individual agent (tree) level a genetic algorithm is used to model the genotypic structure and the genetic processes, from a small set of simple rules, complex higher-order population, and environmental interactions emerge. The program was written in Delphi for the Windows environment, and was designed to be used for educational and research purposes.

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Phillips, Ryan D., Renate Faast, Colin C. Bower, Graham R. Brown e Rod Peakall. "Implications of pollination by food and sexual deception for pollinator specificity, fruit set, population genetics and conservation of Caladenia (Orchidaceae)". Australian Journal of Botany 57, n.º 4 (2009): 287. http://dx.doi.org/10.1071/bt08154.

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Caladenia is very unusual in that it contains species that attract pollinators by two different strategies, food and sexual deception. Among the sexually deceptive species, baiting for pollinators has shown that within populations orchid species are typically pollinated by a single species of thynnine wasp. However, some wasp species can be pollinators of more than one species of orchid usually when their ranges do not overlap. There is a trend for closely related orchids to exploit wasps from the same genus, with different lineages of orchids often pollinated by different genera. Very little is known about pollination of food-deceptive Caladenia species, although it is evident they attract a suite of generalist food-seeking insects. Food-deceptive species have a higher pollination rate than do sexually deceptive species. Studies of population genetics and pollen movements are few, although they suggest a pattern of fine-scale genetic structuring within populations, owing to predominantly restricted seed dispersal and low genetic differentiation among populations as a consequence of rare long-distance seed-dispersal events. Both evolutionary and ecological research of Caladenia will greatly benefit from a better understanding of the insect species involved in pollination, their ecological requirements and the ecological and genetic consequences of food and sexual deception.

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Frisman, E. Ya, O. L. Zhdanova e G. P. Neverova. "Ecological and Genetic Models in Population Biophysics". Biophysics 65, n.º 5 (setembro de 2020): 810–25. http://dx.doi.org/10.1134/s0006350920050061.

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Rehfeldt, G. E. "Ecological genetics of Pinuscontorta in the Wasatch and Uinta Mountains of Utah". Canadian Journal of Forest Research 15, n.º 3 (1 de junho de 1985): 524–30. http://dx.doi.org/10.1139/x85-086.

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Genetic differentiation of 45 populations of Pinuscontorta primarily from the Wasatch and Uinta Mountains was studied in field, greenhouse, and laboratory tests. Analyses of variables reflecting growth potential, morphology, cold hardiness, and periodicity of shoot elongation revealed population differentiation for a variety of traits. Regression models related as much as 77% of the variance among population means to the elevation and geographic location of the seed source. For genetic variation to be arranged along relatively steep environmental clines implies pronounced adaptive differentiation. As a result, seed transfer in reforestation should be restricted severely if maladaptation is to be controlled.

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Pech-May, Angélica, David A. Moo-Llanes, María Belem Puerto-Avila, Mauricio Casas, Rogelio Danis-Lozano, Gustavo Ponce, Ezequiel Tun-Ku et al. "Population genetics and ecological niche of invasive Aedes albopictus in Mexico". Acta Tropica 157 (maio de 2016): 30–41. http://dx.doi.org/10.1016/j.actatropica.2016.01.021.

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Vergara-Chen, Carlos, Fernanda Rodrigues e Mercedes González-Wangüemert. "Population genetics of Cerastoderma edule in Ria Formosa (southern Portugal): the challenge of understanding an intraspecific hotspot of genetic diversity". Journal of the Marine Biological Association of the United Kingdom 95, n.º 2 (7 de outubro de 2014): 371–79. http://dx.doi.org/10.1017/s0025315414001313.

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Coastal lagoons are highly variable environments that may act as hotspots of genetic diversity as a consequence of their ecological role as nursery habitats of marine species with both ecological and fisheries importance. The edible cockle (Cerastoderma edule) is a commercially important shellfish resource inhabiting coastal lagoons in Europe and their fisheries management urgently needs genetic studies to design appropriate strategies to promote the recovery of exploited populations. The aim of this study was to assess the C. edule genetic diversity and population structure at a small geographic scale, inside Ria Formosa coastal lagoon (southern Portugal) using mitochondrial cytochrome oxidase I sequences in six locations. Outcomes pointed to a common pattern of high haplotype diversity and non-significant genetic structuring inside the Ria Formosa lagoon. A high level of gene flow was detected between all localities and the presence of a single stock from a genetic point of view may be considered for fisheries management purposes. The existence of a high number of haplotypes and high values of haplotype diversity of C. edule in Ria Formosa lagoon could be consistent with the hypothesis that higher genetic diversity is expected in populations occurring in coastal lagoons, suggesting that lagoons could increase standing genetic variation and an adaptive potential of lagoon populations as an ecological response to a highly variable environment.

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Peñas, Julio, Sara Barrios, Javier Bobo-Pinilla, Juan Lorite e M. Montserrat Martínez-Ortega. "Designing conservation strategies to preserve the genetic diversity ofAstragalus edulisBunge, an endangered species from western Mediterranean region". PeerJ 4 (18 de janeiro de 2016): e1474. http://dx.doi.org/10.7717/peerj.1474.

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Astragalus edulis(Fabaceae) is an endangered annual species from the western Mediterranean region that colonized the SE Iberian Peninsula, NE and SW Morocco, and the easternmost Macaronesian islands (Lanzarote and Fuerteventura). Although in Spain some conservation measures have been adopted, it is still necessary to develop an appropriate management plan to preserve genetic diversity across the entire distribution area of the species. Our main objective was to use population genetics as well as ecological and phylogeographic data to select Relevant Genetic Units for Conservation (RGUCs) as the first step in designing conservation plans forA. edulis. We identified six RGUCs for in situ conservation, based on estimations of population genetic structure and probabilities of loss of rare alleles. Additionally, further population parameters, i.e. occupation area, population size, vulnerability, legal status of the population areas, and the historical haplotype distribution, were considered in order to establish which populations deserve conservation priority. Three populations from the Iberian Peninsula, two from Morocco, and one from the Canary Islands represent the total genetic diversity of the species and the rarest allelic variation. Ex situ conservation is recommended to complement the preservation ofA. edulis, given that effective in situ population protection is not feasible in all cases. The consideration of complementary phylogeographic and ecological data is useful for management efforts to preserve the evolutionary potential of the species.

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Mosseler, A. "Life history and genetic diversity in red pine: implications for gene conservation in forestry". Forestry Chronicle 68, n.º 6 (1 de dezembro de 1992): 701–8. http://dx.doi.org/10.5558/tfc68701-6.

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Red pine, Pinus resinosa Ait., is a suffusively rare species throughout its geographical range, occurring as small, highly fragmented populations. Such species are particularly vulnerable to the genetic and demographic stochasticity that can lead to local extinction and losses of genetic variation. Red pine illustrates the difficulty that species with long generation times have in recovering genetic diversity once it has been lost. Tree species that lose their genetic diversity may not recover the genetic variation required for effective adaptive responses to environmental challenges. Population declines in rare tree species should be viewed with greater concern by forest managers because the loss of a tree species threatens ecological stability and future economic potential in areas of limited biodiversity. Newfoundland's red pine population provides an example for a broader discussion of concepts in population ecology and genetics useful in developing gene conservation efforts for tree populations characterized by fragmented distributions, small population sizes, and declining population numbers. Key words: population ecology, genetic diversity, gene conservation, metapopulation, reproductive success

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VanInsberghe, David, Philip Arevalo, Diana Chien e Martin F. Polz. "How can microbial population genomics inform community ecology?" Philosophical Transactions of the Royal Society B: Biological Sciences 375, n.º 1798 (23 de março de 2020): 20190253. http://dx.doi.org/10.1098/rstb.2019.0253.

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Populations are fundamental units of ecology and evolution, but can we define them for bacteria and archaea in a biologically meaningful way? Here, we review why population structure is difficult to recognize in microbes and how recent advances in measuring contemporary gene flow allow us to identify clearly delineated populations among collections of closely related genomes. Such structure can arise from preferential gene flow caused by coexistence and genetic similarity, defining populations based on biological mechanisms. We show that such gene flow units are sufficiently genetically isolated for specific adaptations to spread, making them also ecological units that are differentially adapted compared to their closest relatives. We discuss the implications of these observations for measuring bacterial and archaeal diversity in the environment. We show that operational taxonomic units defined by 16S rRNA gene sequencing have woefully poor resolution for ecologically defined populations and propose monophyletic clusters of nearly identical ribosomal protein genes as an alternative measure for population mapping in community ecological studies employing metagenomics. These population-based approaches have the potential to provide much-needed clarity in interpreting the vast microbial diversity in human and environmental microbiomes. This article is part of the theme issue ‘Conceptual challenges in microbial community ecology’.

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Takahashi, Yuma, Ryoya Tanaka, Daisuke Yamamoto, Suzuki Noriyuki e Masakado Kawata. "Balanced genetic diversity improves population fitness". Proceedings of the Royal Society B: Biological Sciences 285, n.º 1871 (17 de janeiro de 2018): 20172045. http://dx.doi.org/10.1098/rspb.2017.2045.

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Although genetic diversity within a population is suggested to improve population-level fitness and productivity, the existence of these effects is controversial because empirical evidence for an ecological effect of genetic diversity and the underlying mechanisms is scarce and incomplete. Here, we show that the natural single-gene behavioural polymorphism ( Rover and sitter ) in Drosophila melanogaster has a positive effect on population fitness. Our simple numerical model predicted that the fitness of a polymorphic population would be higher than that expected with two monomorphic populations, but only under balancing selection. Moreover, this positive diversity effect of genetic polymorphism was attributable to a complementarity effect, rather than to a selection effect. Our empirical tests using the behavioural polymorphism in D. melanogaster clearly supported the model predictions. These results provide direct evidence for an ecological effect of genetic diversity on population fitness and its condition dependence.

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Manier, Mollie K., e Stevan J. Arnold. "Ecological correlates of population genetic structure: a comparative approach using a vertebrate metacommunity". Proceedings of the Royal Society B: Biological Sciences 273, n.º 1604 (23 de agosto de 2006): 3001–9. http://dx.doi.org/10.1098/rspb.2006.3678.

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Identifying ecological factors associated with population genetic differentiation is important for understanding microevolutionary processes and guiding the management of threatened populations. We identified ecological correlates of several population genetic parameters for three interacting species (two garter snakes and an anuran) that occupy a common landscape. Using multiple regression analysis, we found that species interactions were more important in explaining variation in population genetic parameters than habitat and nearest-neighbour characteristics. Effective population size was best explained by census size, while migration was associated with differences in species abundance. In contrast, genetic distance was poorly explained by the ecological correlates that we tested, but geographical distance was prominent in models for all species. We found substantially different population dynamics for the prey species relative to the two predators, characterized by larger effective sizes, lower gene flow and a state of migration-drift equilibrium. We also identified an escarpment formed by a series of block faults that serves as a barrier to dispersal for the predators. Our results suggest that successful landscape-level management should incorporate genetic and ecological data for all relevant species, because even closely associated species can exhibit very different population genetic dynamics on the same landscape.

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Logares, Ramiro. "Population genetics: the next stop for microbial ecologists?" Open Life Sciences 6, n.º 6 (1 de dezembro de 2011): 887–92. http://dx.doi.org/10.2478/s11535-011-0086-9.

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AbstractMicrobes play key roles in the functioning of the biosphere. Still, our knowledge about their total diversity is very limited. In particular, we lack a clear understanding of the evolutionary dynamics occurring within their populations (i.e. among members of the same biological species). Unlike animals and plants, microbes normally have huge population sizes, high reproductive rates and the potential for unrestricted dispersal. As a consequence, the knowledge of population genetics acquired from studying animals and plants cannot be applied without extensive testing to microbes. Next generation molecular tools, like High Throughput Sequencing (e.g. 454 and Illumina) coupled to Single Cell Genomics, now allow investigating microbial populations at a very fine scale. Such techniques have the potential to shed light on several ecological and evolutionary processes occurring within microbial populations that so far have remained hidden. Furthermore, they may facilitate the identification of microbial species. Eventually, we may find an answer to the question of whether microbes and multicellular organisms follow the same or different rules in their population diversification patterns.

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Phillips, P. D., I. S. Thompson, J. N. M. Silva, P. R. van Gardingen e B. Degen. "Scaling up models of tree competition for tropical forest population genetics simulation". Ecological Modelling 180, n.º 2-3 (dezembro de 2004): 419–34. http://dx.doi.org/10.1016/j.ecolmodel.2004.04.029.

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Hollocher, H., A. R. Templeton, R. DeSalle e J. S. Johnston. "The molecular through ecological genetics of abnormal abdomen. IV. Components of genetic variation in a natural population of Drosophila mercatorum." Genetics 130, n.º 2 (1 de fevereiro de 1992): 355–66. http://dx.doi.org/10.1093/genetics/130.2.355.

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Abstract Natural populations of Drosophila mercatorum are polymorphic for a phenotypic syndrome known as abnormal abdomen (aa). This syndrome is characterized by a slow-down in egg-to-adult developmental time, retention of juvenile abdominal cuticle in the adult, increased early female fecundity, and decreased adult longevity. Previous studies revealed that the expression of this syndrome in females is controlled by two closely linked X chromosomal elements: the occurrence of an R1 insert in a third or more of the X-linked 28S ribosomal genes (rDNA), and the failure of replicative selection favoring uninserted 28S genes in larval polytene tissues. The expression of this syndrome in males in a laboratory stock was associated with the deletion of the rDNA normally found on the Y chromosome. In this paper we quantify the levels of genetic variation for these three components in a natural population of Drosophila mercatorum found near Kamuela, Hawaii. Extensive variation is found in the natural population for both of the X-linked components. Moreover, there is a significant association between variation in the proportion of R1 inserted 28S genes with allelic variation at the underreplication (ur) locus such that both of the necessary components for aa expression in females tend to cosegregate in the natural population. Accordingly, these two closely linked X chromosomal elements are behaving as a supergene in the natural population. Because of this association, we do not believe the R1 insert to be actively transposing to an appreciable extent. The Y chromosomes extracted from nature are also polymorphic, with 16% of the Ys lacking the Y-specific rDNA marker. The absence of this marker is significantly associated with the expression of aa in males. Hence, all three of the major genetic determinants of the abnormal abdomen syndrome are polymorphic in this natural population.

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Forbes, Valery E., e Peter Calow. "Population growth rate as a basis for ecological risk assessment of toxic chemicals". Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 357, n.º 1425 (29 de setembro de 2002): 1299–306. http://dx.doi.org/10.1098/rstb.2002.1129.

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Assessing the ecological risks of toxic chemicals is most often based on individual–level responses such as survival, reproduction or growth. Such an approach raises the following questions with regard to translating these measured effects into likely impacts on natural populations. (i) To what extent do individual–level variables underestimate or overestimate population–level responses? (ii) How do toxicant–caused changes in individual–level variables translate into changes in population dynamics for species with different life cycles? (iii) To what extent are these relationships complicated by population–density effects? These issues go to the heart of the ecological relevance of ecotoxicology and we have addressed them using the population growth rate as an integrating concept. Our analysis indicates that although the most sensitive individual–level variables are likely to be equally or more sensitive to increasing concentrations of toxic chemicals than population growth rate, they are difficult to identify a priori and, even if they could be identified, integrating impacts on key life–cycle variables via population growth rate analysis is nevertheless a more robust approach for assessing the ecological risks of chemicals. Populations living under density–dependent control may respond differently to toxic chemicals than exponentially growing populations, and greater care needs to be given to incorporating realistic density conditions (either experimentally or by simulation) into ecotoxicological test designs. It is impractical to expect full life–table studies, which record changes in survival, fecundity and development at defined intervals through the life cycle of organisms under specified conditions, for all relevant species, so we argue that population growth rate analysis should be used to provide guidance for a more pragmatic and ecologically sound approach to ecological risk assessment.

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Reeb, C. A., e J. C. Avise. "A genetic discontinuity in a continuously distributed species: mitochondrial DNA in the American oyster, Crassostrea virginica." Genetics 124, n.º 2 (1 de fevereiro de 1990): 397–406. http://dx.doi.org/10.1093/genetics/124.2.397.

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Abstract Restriction site variation in mitochondrial DNA (mtDNA) of the American oyster (Crassostrea virginica) was surveyed in continuously distributed populations sampled from the Gulf of St. Lawrence, Canada, to Brownsville, Texas. mtDNA clonal diversity was high, with 82 different haplotypes revealed among 212 oysters with 13 endonucleases. The mtDNA clones grouped into two distinct genetic arrays (estimated to differ by about 2.6% in nucleotide sequence) that characterized oysters collected north vs. south of a region on the Atlantic mid-coast of Florida. The population genetic "break" in mtDNA contrasts with previous reports of near uniformity of nuclear (allozyme) allele frequencies throughout the range of the species, but agrees closely with the magnitude and pattern of mtDNA differentiation reported in other estuarine species in the southeastern United States. This concordance of mtDNA phylogenetic pattern across independently evolving species provides strong evidence for vicariant biogeographic processes in initiating intraspecific population structure. The post-Miocene ecological history of the region suggests that reduced precipitation levels in an enlarged Floridian peninsula may have created discontinuities in suitable estuarine habitat for oysters during glacial periods, and that today such population separations are maintained by the combined influence of ecological gradients and oceanic currents on larval dispersal. The results are consistent with the hypothesis that historical vicariant events, in conjunction with contemporary environmental influences on gene flow, can result in genetic discontinuities in continuously distributed species with high dispersal capability.

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Ward, Sarah M., John F. Gaskin e Linda M. Wilson. "Ecological Genetics of Plant Invasion: What Do We Know?" Invasive Plant Science and Management 1, n.º 1 (janeiro de 2008): 98–109. http://dx.doi.org/10.1614/ipsm-07-022.1.

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AbstractThe rate at which plant invasions occur is accelerating globally, and a growing amount of recent research uses genetic analysis of invasive plant populations to better understand the histories, processes, and effects of plant invasions. The goal of this review is to provide natural resource managers with an introduction to this research. We discuss examples selected from published studies that examine intraspecific genetic diversity and the role of hybridization in plant invasion. We also consider the conflicting evidence that has emerged from recent research for the evolution of increased competitiveness as an explanation for invasion, and the significance of multiple genetic characteristics and patterns of genetic diversity reported in the literature across different species invasions. High and low levels of genetic diversity have been found in different invading plant populations, suggesting that either selection leading to local adaptation, or pre-adapted characteristics such as phenotypic plasticity, can lead to aggressive range expansion by colonizing nonnative species. As molecular techniques for detecting hybrids advance, it is also becoming clear that hybridization is a significant component of some plant invasions, with consequences that include increased genetic diversity within an invasive species, generation of successful novel genotypes, and genetic swamping of native plant gene pools. Genetic analysis of invasive plant populations has many applications, including predicting population response to biological or chemical control measures based on diversity levels, identifying source populations, tracking introduction routes, and elucidating mechanisms of local spread and adaptation. This information can be invaluable in developing more effectively targeted strategies for managing existing plant invasions and preventing new ones. Future genetic research, including the use of high throughput molecular marker systems and genomic approaches such as microarray analysis, has the potential to contribute to better understanding and more effective management of plant invasions.

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GLEICHSNER, ALYSSA M., e DENNIS J. MINCHELLA. "Can host ecology and kin selection predict parasite virulence?" Parasitology 141, n.º 8 (24 de abril de 2014): 1018–30. http://dx.doi.org/10.1017/s0031182014000389.

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SUMMARYParasite virulence, or the damage a parasite does to its host, is measured in terms of both host costs (reductions in host growth, reproduction and survival) and parasite benefits (increased transmission and parasite numbers) in the literature. Much work has shown that ecological and genetic factors can be strong selective forces in virulence evolution. This review uses kin selection theory to explore how variations in host ecological parameters impact the genetic relatedness of parasite populations and thus virulence. We provide a broad overview of virulence and population genetics studies and then draw connections to existing knowledge about natural parasite populations. The impact of host movement (transporting parasites) and host resistance (filtering parasites) on the genetic structure and virulence of parasite populations is explored, and empirical studies of these factors using Plasmodium and trematode systems are proposed.

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Davies, Neil, Francis X. Villablanca e George K. Roderick. "Bioinvasions of the Medfly Ceratitis capitata: Source Estimation Using DNA Sequences at Multiple Intron Loci". Genetics 153, n.º 1 (1 de setembro de 1999): 351–60. http://dx.doi.org/10.1093/genetics/153.1.351.

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Abstract The Mediterranean fruit fly, Ceratitis capitata, is a devastating agricultural pest that threatens to become established in vulnerable areas such as California and Florida. Considerable controversy surrounds the status of Californian medfly infestations: Do they represent repeated introductions or the persistence of a resident population? Attempts to resolve this question using traditional population genetic markers and statistical methods are problematic because the most likely source populations in Latin America were themselves only recently colonized and are genetically very similar. Here, significant population structure among several New World medfly populations is demonstrated through the analysis of DNA sequence variation at four intron loci. Surprisingly, in these newly founded populations, estimates of population structure increase when measures of subdivision take into account the relatedness of alleles as well as their frequency. A nonequilibrium, likelihood-based statistical test that utilizes multilocus genotypes suggests that the sole medfly captured in California during 1996 was introduced from Latin America and was less likely to be a remnant of an ancestral Californian population. Many bioinvasions are hierarchical in nature, consisting of several sequential or overlapping invasion events, the totality of which can be termed a metainvasion. Phylogenetic data from multilocus DNA sequences will be vital to understanding the evolutionary and ecological processes that underlie metainvasions and to resolving their constituent levels.

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Neupane, Swatantra, e Sen Xu. "Adaptive Divergence of Meiotic Recombination Rate in Ecological Speciation". Genome Biology and Evolution 12, n.º 10 (28 de agosto de 2020): 1869–81. http://dx.doi.org/10.1093/gbe/evaa182.

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Abstract Theories predict that directional selection during adaptation to a novel habitat results in elevated meiotic recombination rate. Yet the lack of population-level recombination rate data leaves this hypothesis untested in natural populations. Here, we examine the population-level recombination rate variation in two incipient ecological species, the microcrustacean Daphnia pulex (an ephemeral-pond species) and Daphnia pulicaria (a permanent-lake species). The divergence of D. pulicaria from D. pulex involved habitat shifts from pond to lake habitats as well as strong local adaptation due to directional selection. Using a novel single-sperm genotyping approach, we estimated the male-specific recombination rate of two linkage groups in multiple populations of each species in common garden experiments and identified a significantly elevated recombination rate in D. pulicaria. Most importantly, population genetic analyses show that the divergence in recombination rate between these two species is most likely due to divergent selection in distinct ecological habitats rather than neutral evolution.

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Sanders, Ian R. "Intraspecific genetic variation in arbuscular mycorrhizal fungi and its consequences for molecular biology, ecology, and development of inoculum". Canadian Journal of Botany 82, n.º 8 (1 de agosto de 2004): 1057–62. http://dx.doi.org/10.1139/b04-094.

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It has been known for some time that different arbuscular mycorrhizal fungal (AMF) taxa confer differences in plant growth. Although genetic variation within AMF species has been given less attention, it could potentially be an ecologically important source of variation. Ongoing studies on variability in AMF genes within Glomus intraradices indicate that at least for some genes, such as the BiP gene, sequence variability can be high, even in coding regions. This suggests that genetic variation within an AMF may not be selectively neutral. This clearly needs to be investigated in more detail for other coding regions of AMF genomes. Similarly, studies on AMF population genetics indicate high genetic variation in AMF populations, and a considerable amount of variation seen in phenotypes in the population can be attributed to genetic differences among the fungi. The existence of high within-species genetic variation could have important consequences for how investigations on AMF gene expression and function are conducted. Furthermore, studies of within-species genetic variability and how it affects variation in plant growth will help to identify at what level of precision ecological studies should be conducted to identify AMF in plant roots in the field. A population genetic approach to studying AMF genetic variability can also be useful for inoculum development. By knowing the amount of genetic variability in an AMF population, the maximum and minimum numbers of spores that will contain a given amount of genetic diversity can be estimated. This could be particularly useful for developing inoculum with high adaptability to different environments.Key words: arbuscular mycorrhizas, symbiosis, genomics, genetic diversity, population genetics, evolutionary ecology.

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Moran, G. F., J. C. Bell e K. G. Eldridge. "The genetic structure and the conservation of the five natural populations of Pinusradiata". Canadian Journal of Forest Research 18, n.º 5 (1 de maio de 1988): 506–14. http://dx.doi.org/10.1139/x88-074.

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Pinusradiata is restricted to three mainland coastal populations in California and two island populations off Baja California, Mexico. In this study each population was divided into two geographic stands based on natural disjunctions within populations. In addition to the division mentioned above, each mainland population was also divided into a number of ecological stands based on ecological and environmental criteria. Genetic variation was measured by analysing 31 allozyme loci electrophoretically using germinated seed from 272 families across all stands and populations. Moderate levels of allozyme variation were found as shown by population averages for mean number of alleles per locus (1.79), percent polymorphic loci (46.4%, 0.99 criterion), and expected heterozygosity (0.098). In fact, the overall genetic diversity in P. radiata (HT = 0.117) is low compared with that of other conifers. In comparison with populations, the levels of allozyme variation in both ecological and geographic stands were slightly lower (means across ecological stands: A = 1.56, P = 39.3%, and He = 0.095). Of the total genetic diversity in P. radiata, 16.2% could be apportioned between populations, a high proportion for a conifer. In contrast, only 2.0 and 1.3% of the genetic diversity on average within mainland populations was between ecological and geographic stands, respectively. These results indicate a low level of genetic differentiation within populations, at least based on the ecological or geographic criteria used in this study. The implications and usefulness of these findings for the development of insitu conservation strategies are discussed.

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Quiroga, M. Paula, Lucia Castello, Vilma Quipildor e Andrea C. Premoli. "Biogeographically significant units in conservation: a new integrative concept for conserving ecological and evolutionary processes". Environmental Conservation 46, n.º 4 (30 de agosto de 2019): 293–301. http://dx.doi.org/10.1017/s0376892919000286.

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SummaryWe combined tools of phylogeography, population genetics and biogeographical interpretation to analyse a group of phylogenetically independent lineages (animals and plants) that coexist within the same geographical region, yet under markedly different environments, in order to identify generalized barriers for gene flow. We tested the hypothesis that major geographic features have produced a concordant genetic structure in phylogenetically independent lineages. A rigorous bibliographic search was performed, selecting available molecular information from six taxa occupying distinct southern biomes of South America: Yungas, Prepuna, Puna and northern Monte. We estimated within-population genetic diversity, the genetic structure and haplotype phylogenies to assemble distribution maps of genetic barriers for each species. We found a strong association between genetic variation and latitudinal distribution of populations. We detected a major barrier for six taxa at 27°S latitude and a second one for a group of three species at 25–26°S. Two alternative non-exclusive hypotheses – geology and/or climate – explain concordant genetic barriers in divergent lineages. We suggest that the term ‘biogeographically significant units’ portrays a group of populations of phylogenetically unrelated taxa that inhabit the same geographic region that have been similarly impacted by major physical events, which can be used to identify priority areas in landscape conservation.

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Lucic, Aleksandar, Vasilije Isajev, Rade Cvjeticanin, Ljubinko Rakonjac, Marijana Novakovic, Ana Nikolic e Snezana Mladenovic-Drinic. "Interpopulation genetic-ecological variation of Scots pine (Pinus sylvestris L.) in Serbia". Genetika 43, n.º 1 (2011): 1–18. http://dx.doi.org/10.2298/gensr1101001l.

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The genetic-ecological variation of Scots pine (Pinus sylvestris L.) in Serbia was studied in the populations at five localities in western and south-western Serbia. Three groups of Scots pine (Pinus sylvestris L.) populations were differentiated based on genetic research (seed protein analysis) and plant community research. The first group consists of Scots pine populations on Sargan (FMU ?Sargan?) and on Tara (FMU ?Kaluderske Bare?), where the forests belong to the community of Scots pine and Austrian pine (Pinetum sylvestris-nigrae Pavlovic 1951). The second group covers the localities Stolovi (FMU ?Radocelo-Crepuljnik?) and Zlatar (FMU ?Zlatar I?), where the forests belong to the community of Scots pine and spruce (Piceo abietis-Pinetum sylvestris Stefanovic 1960). The third group comprises the Scots pine population on Pester (FMU ?Dubocica-Bare?) which belongs to the community of Scots pine with erica (Erico-Pinetum sylvestris Stefanovic 1963). Cluster analysis was performed on the basis of seed protein data and showed that there are three groups of Scots pine populations. The three populations coincide with plant communities. The community of Scots pine with erica (Erico-Pinetum sylvestris Stefanovic 1963) recorded on Pester at the locality ?Dubocica- Bare? in the area of FE ?Golija? Ivanjica, is a special Scots pine population displayed at the greatest distance from all other populations in the cluster analysis dendrogram.

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de Vries, Charlotte, e Hal Caswell. "Stage-Structured Evolutionary Demography: Linking Life Histories, Population Genetics, and Ecological Dynamics". American Naturalist 193, n.º 4 (abril de 2019): 545–59. http://dx.doi.org/10.1086/701857.

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Berry, R. J., e M. E. Jakobson. "Ecological genetics of an island population of the House mouse (Mus musculus)". Journal of Zoology 175, n.º 4 (20 de agosto de 2009): 523–40. http://dx.doi.org/10.1111/j.1469-7998.1975.tb01415.x.

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WANG, TianRui, Li FENG e Fang DU. "New approaches for ecological adaptation study: from population genetics to landscape genomics". SCIENTIA SINICA Vitae 51, n.º 2 (6 de janeiro de 2021): 167–78. http://dx.doi.org/10.1360/ssv-2020-0265.

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Lara-Cabrera, Sabina I., Nancy Alejandre-Melena, Edgar I. Medina-Sánchez e Roberto Lindig-Cisneros. "GENETIC DIVERSITY IN POPULATIONS OF Lupinus Elegans KUNTH, IMPLICATIONS FOR ECOLOGICAL RESTORATION". Revista Fitotecnia Mexicana 32, n.º 2 (30 de junho de 2009): 79–86. http://dx.doi.org/10.35196/rfm.2009.2.79-86.

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Lupinus elegans Kunth is a common species in the West-Central region of México. L. elegans has been used for the restoration of degraded conifer forests because it creates microenvironments suitable for the establishment of coniferous species by increasing nitrogen concentrations in the soil. In this study we determined the genetic variation of L. elegans populations using RAPD markers. One hundred and fifty individuals were collected from five populations in Michoacán: Llano de Pario, Charapan, Pico de Tancítaro, San Nicolás and Villa Madero. Results indicate genetic variation (h) about 0.20 with 60 % polymorphism. The molecular analysis showed higher genetic variation within (59 %) than between (41 %) populations. A Neighbor Joining tree was generated based on Nei's genetic distances, and the resulting tree clustered the populations of Llano de Pario and San Nicolás, followed by populations of Tancítaro, and lastly clustered Villa Madero and Charapan. No correlation was found between genetic and geographic distances. Common garden experiments indicate that plants from the local population out perform introduced plants. These results suggest that although L. elegans is a species with a considerable geographic range, seed collection for restoration purposes should be done from the closest (geographical)population possible.

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Slynko, Е. Е., Y. V. Slynko e V. I. Rabushko. "Adaptive strategy of Rapana venosa (Gastropoda, Muricidae) in the invasive population of the Black Sea". Biosystems Diversity 28, n.º 1 (10 de fevereiro de 2020): 48–52. http://dx.doi.org/10.15421/012008.

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We conducted molecular-genetic and morphological studies on the veined rapa whelk Rapana venosa (Valenciennes, 1846) in the Crimean waters of the Black Sea in order to determine possible reasons of the invasive success of this mollusk. Molecular-genetic tests were performed using COI gene; the surveyed samples reliably identified to R. venosa species. We compared the data on initial (from the Far-Eastern seas) and some invasive populations. In the natural conditions of the Yellow, East China Seas, and the Sea of Japan, the genetic diversity of rapa whelk is high (Hd = 0.933, π = 0.002). In all the invasive populations of rapa whelk (Black Sea, European and North American), an extremely low level of haplotypic and nucleotide diversity was determined (Hd = 0.0, π = 0.0). Despite low values of genetic diversity, the invasive populations of rapa whelk are characterized by ecological success. We noted stable growth of populations, tolerance to diseases and parasites, effective reproduction, high fertility. This contradicts the main provisions of the population genetics theory of formation of edge of range populations, because usually only a small number of specimens of rapa whelk were introduced. The explanations of the unique condition of the invasive populations of rapa whelk, both from an ecological perspective (high resistance to fluctuations of hydrological factors and chemical pollution, absence of enemies, high fertility) and genetic perspective (high selective value of separate haplotypes settled in the new water areas) have not been confirmed. We determined that a very important factor for the naturalization of the rapa whelk at low genetic diversity is the intra-species morpho-ecological divergence. In the Crimean water area of the Black Sea, R. venosa was found to have two morpho-ecological forms associated with the peculiarities of the development of the proportions of the shell. Study of successful invasive species would allow timely and adequate reaction to new cases of introduction.

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Le Sage, Emily H., Sarah I. Duncan, Travis Seaborn, Jennifer Cundiff, Leslie J. Rissler e Erica J. Crespi. "Ecological adaptation drives wood frog population divergence in life history traits". Heredity 126, n.º 5 (3 de fevereiro de 2021): 790–804. http://dx.doi.org/10.1038/s41437-021-00409-w.

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Artigos de revistas sobre o tema "Population and ecological genetics"

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