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A landscape genetics approach to unravel the complex evolutionary history of the Iberian honey bee hybrid zone

Pinto, M. Alice; Johnston, J. Spencer; Azevedo, João; Brandão, Andreia; Moura, Inês; Muñoz, Irene; De la Rúa, Pilar; Patton, John C.
Fonte: IPB, IUFRO Publicador: IPB, IUFRO
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
66.5%
While landscape genetics is in its infancy, it is a rapidly growing research field in part owing to the increasing availability of powerful molecular and analytical tools. By integrating landscape ecology, spatial statistics and population genetics, landscape genetics is allowing an unprecedented understanding of the microevolutionary processes shaping genetic variation, which has important implications for the advance of ecological and evolutionary knowledge. The Iberian honey bee provides a great model system to address evolutionary questions using a landscape genetics framework. First, previous studies suggest that the Iberian honey bee has a hybrid origin and hybrid zones have been favored by evolutionary biologists as powerful natural laboratories to study evolutionary processes. Second, with the publication of the honey bee genome and development of high‐density SNP markers, powerful tools are now available to dissect the relative importance of neutral and adaptive forces in shaping the Iberian honey bee hybrid zone, a goal of central importance as it leads to more robust inferences of demographic history and to identification of adaptive divergence. Herein, we will present an ongoing research project on the Iberian honey bee hybrid zone where the tools of landscape genetics and population genomics will be combined to unravel the challenging evolutionary history of the Iberian honey bee.

Concordant Phylogeographies of 2 Malaria Vectors Attest to Common Spatial and Demographic Histories

PEDRO, Pedro M.; UEZU, Alexandre; SALLUM, Maria Anice Mureb
Fonte: OXFORD UNIV PRESS INC Publicador: OXFORD UNIV PRESS INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.21%
The phylogeography of South American lineages is a topic of heated debate. Although a single process is unlikely to describe entire ecosystems, related species, which incur similar habitat limitations, can inform the history for a subsection of assemblages. We compared the phylogeographic patterns of the cytochrome oxidase I marker from Anopheles triannulatus (N = 72) and previous results for A. darlingi (N = 126) in a broad portion of their South American distributions. Both species share similar population subdivisions, with aggregations northeast of the Amazon River, in southern coastal Brazil and 2 regions in central Brazil. The average (ST) between these groups was 0.39 for A. triannulatus. Populations northeast of the Amazon and in southeastern Brazil are generally reciprocally monophyletic to the remaining groups. Based on these initial analyses, we constructed the a priori hypothesis that the Amazon and regions of high declivity pose geographic barriers to dispersal in these taxa. Mantel tests confirmed that these areas block gene flow for more than 1000 km for both species. The efficacy of these impediments was tested using landscape genetics, which could not reject our a priori hypothesis but did reject simpler scenarios. Results form summary statistics and phylogenetics suggest that both lineages originated in central Amazonia (south of the Amazon River) during the late Pleistocene (579 000 years ago) and that they followed the same paths of expansion into their contemporary distributions. These results may have implications for other species sharing similar ecological limitations but probably are not applicable as a general paradigm of Neotropical biogeography.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo FAPESP[05/53973-0]; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo FAPESP[08/06099-0]

The influence of landscape characteristics and home-range size on the quantification of landscape-genetics relationships

Graves, Tabitha A.; Wasserman, Tzeidle N.; Ribeiro, Milton Cezar; Landguth, Erin L.; Spear, Stephen F.; Balkenhol, Niko; Higgins, Colleen B.; Fortin, Marie-Josee; Cushman, Samuel A.; Waits, Lisette P.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 253-266
ENG
Relevância na Pesquisa
46.33%
A common approach used to estimate landscape resistance involves comparing correlations of ecological and genetic distances calculated among individuals of a species. However, the location of sampled individuals may contain some degree of spatial uncertainty due to the natural variation of animals moving through their home range or measurement error in plant or animal locations. In this study, we evaluate the ways that spatial uncertainty, landscape characteristics, and genetic stochasticity interact to influence the strength and variability of conclusions about landscape-genetics relationships. We used a neutral landscape model to generate 45 landscapes composed of habitat and non-habitat, varying in percent habitat, aggregation, and structural connectivity (patch cohesion). We created true and alternate locations for 500 individuals, calculated ecological distances (least-cost paths), and simulated genetic distances among individuals. We compared correlations between ecological distances for true and alternate locations. We then simulated genotypes at 15 neutral loci and investigated whether the same influences could be detected in simple Mantel tests and while controlling for the effects of isolation-by distance using the partial Mantel test. Spatial uncertainty interacted with the percentage of habitat in the landscape...

A landscape genetics approach to a contact zone of two salamandra salamandra subspecies in southwest Portugal

Silva, Ana Catarina Afonso, 1988-
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2011 ENG
Relevância na Pesquisa
46.38%
Tese de mestrado. Biologia (Biologia Evolutiva e do Desenvolvimento). Universidade de Lisboa, Faculdade de Ciências, 2011; The fire salamander (Salamandra salamandra) is distributed in the center and south of Europe and has a high genetic and morphological variability. In Portugal there are two subspe-cies described, S. s. gallaica with a northern and central distribution and S. s crespoi with a more restricted distribution in the south. Defining the geographical boundaries between populations and subspecies is frequent-ly difficult because there are often uncertainties on their distribution limits at putative or proven contact areas. One approach being increasingly used to detect cryptic geographic boundaries between populations is landscape genetics. This is an emerging field that inte-grates population genetics, landscape ecology and spatial statistics and it aims to provide in-formation about the interaction between landscape features and microevolutionary processes. I attempted here to determine the geographic distribution and limits of the two aforemen-tioned subspecies at their putative contact zone in southwest Portugal, using data from mi-crosatellites and the mitochondrial gene cytochrome-b analysed with landscape genetics tools. This approach allowed evaluating if the two subspecies are currently in allopatry and the oc-currence of gene flow between them. Results show that the two subspecies are separated by a narrow barrier that contains the Sado River and imposes a very reduced gene flow...

A review of techniques for spatial modeling in geographical, conservation and landscape genetics

Diniz-Filho,José Alexandre Felizola; Nabout,João Carlos; Telles,Mariana Pires de Campos; Soares,Thannya Nascimento; Rangel,Thiago Fernando L.V.B.
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
Relevância na Pesquisa
46.17%
Most evolutionary processes occur in a spatial context and several spatial analysis techniques have been employed in an exploratory context. However, the existence of autocorrelation can also perturb significance tests when data is analyzed using standard correlation and regression techniques on modeling genetic data as a function of explanatory variables. In this case, more complex models incorporating the effects of autocorrelation must be used. Here we review those models and compared their relative performances in a simple simulation, in which spatial patterns in allele frequencies were generated by a balance between random variation within populations and spatially-structured gene flow. Notwithstanding the somewhat idiosyncratic behavior of the techniques evaluated, it is clear that spatial autocorrelation affects Type I errors and that standard linear regression does not provide minimum variance estimators. Due to its flexibility, we stress that principal coordinate of neighbor matrices (PCNM) and related eigenvector mapping techniques seem to be the best approaches to spatial regression. In general, we hope that our review of commonly used spatial regression techniques in biology and ecology may aid population geneticists towards providing better explanations for population structures dealing with more complex regression problems throughout geographic space.

A Spatial Statistical Model for Landscape Genetics

Guillot, Gilles; Estoup, Arnaud; Mortier, Frédéric; Cosson, Jean François
Fonte: Genetics Society of America Publicador: Genetics Society of America
Tipo: Artigo de Revista Científica
Publicado em /07/2005 EN
Relevância na Pesquisa
56.35%
Landscape genetics is a new discipline that aims to provide information on how landscape and environmental features influence population genetic structure. The first key step of landscape genetics is the spatial detection and location of genetic discontinuities between populations. However, efficient methods for achieving this task are lacking. In this article, we first clarify what is conceptually involved in the spatial modeling of genetic data. Then we describe a Bayesian model implemented in a Markov chain Monte Carlo scheme that allows inference of the location of such genetic discontinuities from individual geo-referenced multilocus genotypes, without a priori knowledge on populational units and limits. In this method, the global set of sampled individuals is modeled as a spatial mixture of panmictic populations, and the spatial organization of populations is modeled through the colored Voronoi tessellation. In addition to spatially locating genetic discontinuities, the method quantifies the amount of spatial dependence in the data set, estimates the number of populations in the studied area, assigns individuals to their population of origin, and detects individual migrants between populations, while taking into account uncertainty on the location of sampled individuals. The performance of the method is evaluated through the analysis of simulated data sets. Results show good performances for standard data sets (e.g....

Landscape genetics and the spatial distribution of chronic wasting disease

Blanchong, Julie A; Samuel, Michael D; Scribner, Kim T; Weckworth, Byron V; Langenberg, Julia A; Filcek, Kristine B
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.34%
Predicting the spread of wildlife disease is critical for identifying populations at risk, targeting surveillance and designing proactive management programmes. We used a landscape genetics approach to identify landscape features that influenced gene flow and the distribution of chronic wasting disease (CWD) in Wisconsin white-tailed deer. CWD prevalence was negatively correlated with genetic differentiation of study area deer from deer in the area of disease origin (core-area). Genetic differentiation was greatest, and CWD prevalence lowest, in areas separated from the core-area by the Wisconsin River, indicating that this river reduced deer gene flow and probably disease spread. Features of the landscape that influence host dispersal and spatial patterns of disease can be identified based on host spatial genetic structure. Landscape genetics may be used to predict high-risk populations based on their genetic connection to infected populations and to target disease surveillance, control and preventative activities.

Landscape Genetics Reveals Focal Transmission of a Human Macroparasite

Criscione, Charles D.; Anderson, Joel D.; Sudimack, Dan; Subedi, Janardan; Upadhayay, Ram P.; Jha, Bharat; Williams, Kimberly D.; Williams-Blangero, Sarah; Anderson, Timothy J. C.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 20/04/2010 EN
Relevância na Pesquisa
46.18%
Macroparasite infections (e.g., helminths) remain a major human health concern. However, assessing transmission dynamics is problematic because the direct observation of macroparasite dispersal among hosts is not possible. We used a novel landscape genetics approach to examine transmission of the human roundworm Ascaris lumbricoides in a small human population in Jiri, Nepal. Unexpectedly, we found significant genetic structuring of parasites, indicating the presence of multiple transmission foci within a small sampling area (∼14 km2). We analyzed several epidemiological variables, and found that transmission is spatially autocorrelated around households and that transmission foci are stable over time despite extensive human movement. These results would not have been obtainable via a traditional epidemiological study based on worm counts alone. Our data refute the assumption that a single host population corresponds to a single parasite transmission unit, an assumption implicit in many classic models of macroparasite transmission. Newer models have shown that the metapopulation-like pattern observed in our data can adversely affect targeted control strategies aimed at community-wide impacts. Furthermore, the observed metapopulation structure and local mating patterns generate an excess of homozygotes that can accelerate the spread of recessive traits such as drug resistance. Our study illustrates how molecular analyses complement traditional epidemiological information in providing a better understanding of parasite transmission. Similar landscape genetic approaches in other macroparasite systems will be warranted if an accurate depiction of the transmission process is to be used to inform effective control strategies.

The landscape genetics of infectious disease emergence and spread

Biek, Roman; Real, Leslie A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.3%
The spread of parasites is inherently a spatial process often embedded in physically complex landscapes. It is therefore not surprising that infectious disease researchers are increasingly taking a landscape genetics perspective to elucidate mechanisms underlying basic ecological processes driving infectious disease dynamics and to understand the linkage between spatially-dependent population processes and the geographic distribution of genetic variation within both hosts and parasites. The increasing availability of genetic information on hosts and parasites when coupled to their ecological interactions can lead to insights for predicting patterns of disease emergence, spread, and control. Here, we review research progress in this area based on four different motivations for the application of landscape genetics approaches: (1) assessing the spatial organization of genetic variation in parasites as a function of environmental variability, (2) using host population genetic structure as a means to parameterize ecological dynamics that indirectly influence parasite populations, e.g. gene flow and movement pathways across heterogeneous landscapes and the concurrent transport of infectious agents, (3) elucidating the temporal and spatial scales of disease processes...

Spatial Genetic Structure of a Symbiotic Beetle-Fungal System: Toward Multi-Taxa Integrated Landscape Genetics

James, Patrick M. A.; Coltman, Dave W.; Murray, Brent W.; Hamelin, Richard C.; Sperling, Felix A. H.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/10/2011 EN
Relevância na Pesquisa
46.3%
Spatial patterns of genetic variation in interacting species can identify shared features that are important to gene flow and can elucidate co-evolutionary relationships. We assessed concordance in spatial genetic variation between the mountain pine beetle (Dendroctonus ponderosae) and one of its fungal symbionts, Grosmanniaclavigera, in western Canada using neutral genetic markers. We examined how spatial heterogeneity affects genetic variation within beetles and fungi and developed a novel integrated landscape genetics approach to assess reciprocal genetic influences between species using constrained ordination. We also compared landscape genetic models built using Euclidean distances based on allele frequencies to traditional pair-wise Fst. Both beetles and fungi exhibited moderate levels of genetic structure over the total study area, low levels of structure in the south, and more pronounced fungal structure in the north. Beetle genetic variation was associated with geographic location while that of the fungus was not. Pinevolume and climate explained beetle genetic variation in the northern region of recent outbreak expansion. Reciprocal genetic relationships were only detectedin the south where there has been alonger history of beetle infestations. The Euclidean distance and Fst-based analyses resulted in similar models in the north and over the entire study area...

Landscape Genetics for the Empirical Assessment of Resistance Surfaces: The European Pine Marten (Martes martes) as a Target-Species of a Regional Ecological Network

Ruiz-González, Aritz; Gurrutxaga, Mikel; Cushman, Samuel A.; Madeira, María José; Randi, Ettore; Gómez-Moliner, Benjamin J.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 16/10/2014 EN
Relevância na Pesquisa
46.27%
Coherent ecological networks (EN) composed of core areas linked by ecological corridors are being developed worldwide with the goal of promoting landscape connectivity and biodiversity conservation. However, empirical assessment of the performance of EN designs is critical to evaluate the utility of these networks to mitigate effects of habitat loss and fragmentation. Landscape genetics provides a particularly valuable framework to address the question of functional connectivity by providing a direct means to investigate the effects of landscape structure on gene flow. The goals of this study are (1) to evaluate the landscape features that drive gene flow of an EN target species (European pine marten), and (2) evaluate the optimality of a regional EN design in providing connectivity for this species within the Basque Country (North Spain). Using partial Mantel tests in a reciprocal causal modeling framework we competed 59 alternative models, including isolation by distance and the regional EN. Our analysis indicated that the regional EN was among the most supported resistance models for the pine marten, but was not the best supported model. Gene flow of pine marten in northern Spain is facilitated by natural vegetation, and is resisted by anthropogenic landcover types and roads. Our results suggest that the regional EN design being implemented in the Basque Country will effectively facilitate gene flow of forest dwelling species at regional scale.

Modelling the dispersal of the two main hosts of the raccoon rabies variant in heterogeneous environments with landscape genetics

Rioux Paquette, Sébastien; Talbot, Benoit; Garant, Dany; Mainguy, Julien; Pelletier, Fanie
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.23%
Predicting the geographic spread of wildlife epidemics requires knowledge about the movement patterns of disease hosts or vectors. The field of landscape genetics provides valuable approaches to study dispersal indirectly, which in turn may be used to understand patterns of disease spread. Here, we applied landscape genetic analyses and spatially explicit models to identify the potential path of raccoon rabies spread in a mesocarnivore community. We used relatedness estimates derived from microsatellite genotypes of raccoons and striped skunks to investigate their dispersal patterns in a heterogeneous landscape composed predominantly of agricultural, forested and residential areas. Samples were collected in an area covering 22 000 km2 in southern Québec, where the raccoon rabies variant (RRV) was first detected in 2006. Multiple regressions on distance matrices revealed that genetic distance among male raccoons was strictly a function of geographic distance, while dispersal in female raccoons was significantly reduced by the presence of agricultural fields. In skunks, our results suggested that dispersal is increased in edge habitats between fields and forest fragments in both males and females. Resistance modelling allowed us to identify likely dispersal corridors used by these two rabies hosts...

O papel da estrutura da paisagem na variabilidade genética da palmeira Euterpe edulis na Mata Atlântica; The role of landscape structure on genetic variability of the palm Euterpe edulis along the Atlantic rainforest

Carvalho, Carolina da Silva
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ecologia e Evolução (ICB); Instituto de Ciências Biológicas - ICB (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ecologia e Evolução (ICB); Instituto de Ciências Biológicas - ICB (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
46.18%
Não consta resumo em outro idioma.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES; Essa dissertação está estruturada em dois capítulos cujo objetivo geral foi entender como características da paisagem influenciam a variação e a estruturação genética, usando a abordagem de genética da paisagem e a palmeira Euterpe edulis (Arecaceae) como modelo de estudo. A genética da paisagem surgiu a partir da junção de três grandes áreas da ciência: ecologia da paisagem, ecologia espacial e genética de populações (Manel et al. 2003). Difere-se de disciplinas clássicas como genética de populações e filogeografia, pois incorpora testes explícitos de heterogeneidade ambiental a fim de entender a distribuição da variabilidade genética no espaço (Storfer et al. 2007). Dentre as abordagens frequentemente realizadas na genética da paisagem podemos: identificar características da paisagem que influenciam a conectividade e diversidade genética, realizar design de corredores ecológicos e reservas, e predizer impactos de futuras mudanças ambientais na conectividade e permanência da espécie (Spear et al. 2010). No entanto, a primeira abordagem é a mais utilizada nos estudos, onde são testados o efeito do relevo...

Comparative landscape genetics of two sympatric snake species in a fragmented southwestern Ontario habitat

DiLeo, Michelle
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 702161 bytes; application/pdf
EN
Relevância na Pesquisa
56.23%
In this study I investigate the effects of a fragmented southwestern Ontario landscape on the genetic population structure of two sympatric snake species that differ in habitat preference. I was most interested in comparing the relative number and location of both natural and human-created barriers to gene flow between the species. The eastern garter snake (Thamnophis sirtalis) is a common species and a habitat generalist, whereas the eastern foxsnake (Elaphe gloydi) is less common, geographically isolated, and a marsh-specialist. Bayesian spatial assignment revealed three genetic clusters for garter snakes and five genetic clusters for foxsnakes. Each individual garter snake had a near equal probability of membership to two or more clusters with none of the clusters mapping onto a discrete geographic region, indicating that in reality T. sirtalis in southwestern Ontario probably exist in a single genetic population. The five identified foxsnake clusters correspond to geographically circumscribed locations on the Southern Ontario landscape. Slopes of pair-wise isolation by distance between individuals were significantly different from zero, but extremely weak, for both species. Isolation by distance was found to be greater in foxsnakes compared to garter snakes. The results of this study imply that foxsnakes experience more barriers to gene flow than garter snakes across southwestern Ontario.

Population structure and connectivity in a small woodland snake

Jamison, Caroline
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
46.46%
A heterogeneous landscape contributes to the genetic structure of natural populations by aiding or impeding the dispersal of individuals across it, affecting gene flow between local populations. Traditional population genetics methods (e.g. FST ) do not account for landscape factors into account when assessing genetic structure, the emerging discipline of landscape genetics looks specifically at how landscape features affect population structure and connectivity. I used a landscape genetics approach to investigate genetic population structure in the ringneck snake (Diadophis punctatus), a small-bodied snake of temperate forests, in the Georgian Bay region of Central Ontario, Canada. Because of its small size, putative preference for forested habitat and presumed low dispersal ability I expected to find marked population structure at a fine scale within the study area and further expected that open habitat and roads would act as partial barriers to gene flow. To test these hypotheses I used genotypic data from five microsatellite loci and a spatial assignment test, spatial autocorrelation, and isolation by landscape resistance analyses to determine the extent of population structure and the effect of landscape features on genetic structure. Contrary to my hypotheses...

Landscape genetics of Phaedranassa herb. (Amaryllidaceae) in Ecuador

Oleas Gallo, Nora Helena
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.17%
Speciation can be understood as a continuum occurring at different levels, from population to species. The recent molecular revolution in population genetics has opened a pathway towards understanding species evolution. At the same time, speciation patterns can be better explained by incorporating a geographic context, through the use of geographic information systems (GIS). Phaedranassa (Amaryllidaceae) is a genus restricted to one of the world’s most biodiverse hotspots, the Northern Andes. I studied seven Phaedranassa species from Ecuador. Six of these species are endemic to the country. The topographic complexity of the Andes, which creates local microhabitats ranging from moist slopes to dry valleys, might explain the patterns of Phaedranassa species differentiation. With a Bayesian individual assignment approach, I assessed the genetic structure of the genus throughout Ecuador using twelve microsatellite loci. I also used bioclimatic variables and species geographic coordinates under a Maximum Entropy algorithm to generate distribution models of the species. My results show that Phaedranassa species are genetically well-differentiated. Furthermore, with the exception of two species, all Phaedranassa showed non-overlapping distributions. Phaedranassa viridiflora and P. glauciflora were the only species in which the model predicted a broad species distribution...

A landscape genetics approach for quantifying the relative influence of historic and contemporary habitat heterogeneity on the genetic connectivity of a rainforest bird

Pavlacky, D.; Goldizen, A.; Prentis, P.; Nicholls, J.; Lowe, A.
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
46.41%
Landscape genetics is an important framework for investigating the influence of spatial pattern on ecological process. Nevertheless, the standard analytic frameworks in landscape genetics have difficulty evaluating hypotheses about spatial processes in dynamic landscapes. We use a predictive hypothesis-driven approach to quantify the relative contribution of historic and contemporary processes to genetic connectivity. By confronting genetic data with models of historic and contemporary landscapes, we identify dispersal processes operating in naturally heterogeneous and human-altered systems. We demonstrate the approach using a case study of microsatellite polymorphism and indirect estimates of gene flow for a rainforest bird, the logrunner (Orthonyx temminckii). Of particular interest was how much information in the genetic data was attributable to processes occurring in the reconstructed historic landscape and contemporary human-modified landscape. A linear mixed model was used to estimate appropriate sampling variance from nonindependent data and information-theoretic model selection provided strength of evidence for alternative hypotheses. The contemporary landscape explained slightly more information in the genetic differentiation data than the historic landscape...

Exploring Geovisualization Symbology for Landscape Genetics

MAC AOIDH EOIN; MARTINSOHN Jann; MAES Gregory; CARIANI Alessia; NIELSEN Einar Eg
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Articles in Journals Formato: Online
ENG
Relevância na Pesquisa
46.23%
Landscape genetics, which considers genetic population structure in the context of spatially referenced parameters in the surrounding landscape, has been shown to be extremely useful for wildlife management. Unfortunately its widespread uptake beyond the research community is hampered due to a lack of effective communication of useable information in a suitable format for application by stakeholders such as wildlife regulators or managers. To improve the communication of suitable information, geovisualization of results should be facilitated in a comprehensible format for stakeholders without GIS or genetic expertise. Existing Web-based solutions do not provide adequate support for the visualization of multi-attribute spatially referenced genetic population structure information. As a solution, we propose an appropriate symbology to communicate landscape genetic information through the existing suite of web-based spatial software provided by the OpenGeo Stack. A full problem description, review of available technologies, development rationale, and theoretical implementation of the proposed symbology are provided.; JRC.G.4-Maritime affairs

The influence of landscape on genetic structure of a threatened reptile: the eastern massasauga rattlesnake

DiLeo, Michelle Francis
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
46.35%
Understanding the impacts of both natural and anthropogenic landscape features on genetic diversity, population structure and connectivity has important implications for conservation of species living in fragmented environments. Here, I combine population genetic data, detailed land cover information, and computer simulations to explore how landscape shapes genetic structure across two regional populations of the threatened eastern massasauga rattlesnake (Sistrurus catenatus catenatus) in Ontario, Canada: one along the eastern shores of Georgian Bay and the other largely confined to the northern half of the Bruce Peninsula. First I used spatial Bayesian assignment to quantify the genetic population structure within each regional population. I found marked subpopulation structure within eastern Georgian Bay with differentiation of island and mainland snakes, a north-south split within the mainland coinciding with the town of Parry Sound, and evidence of further subdivision within the cluster of snakes north of Parry Sound. In contrast I found no population subdivision within the mainland of the Bruce Peninsula, but genetic distinction of mainland and island snakes. Next, I identified the landscape features that shape spatial genetic structure within regional populations. In eastern Georgian Bay I found local variation in the effect of landscape on populations. North of Parry Sound I found no effect of landscape on inter-individual genetic differentiation...

CHARACTERIZING POPULATION GENETIC STRUCTURE AND INFERRING THE INFLUENCE OF LANDSCAPE FEATURES ON GENE FLOW IN A TEMPERATE SNAKE SPECIES

Xuereb, Amanda
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
46.34%
Patterns of genetic diversity in natural systems are influenced by landscape heterogeneity over spatial and temporal scales. Certain natural or anthropogenic landscape features may facilitate or impede organism dispersal and subsequent gene flow. Characterizing the geographical distribution of genetic diversity and identifying the factors contributing to population genetic structure is imperative for maintaining functional connectivity between isolated populations across a fragmented landscape. In this study, I combined genetic data and high-resolution land cover information to investigate patterns of population genetic structure in the threatened eastern hog-nosed snake (Heterodon platirhinos) at its northern range limit in Ontario, Canada. First, using putatively neutral microsatellite markers, I found evidence of genetic differentiation between two geographically disjunct regional populations: in the Carolinian region of southwestern Ontario, and along the eastern shoreline of Georgian Bay. Spatial and non-spatial Bayesian clustering algorithms also detected population genetic structure within each regional population. I found evidence of weak structure within Georgian Bay, roughly corresponding to regions north and south of Parry Sound. A genetic cluster at Wasaga Beach...