Abstract The amount and distribution of genetic diversity are likely to affect the evolutionary potential of a species. When feasible and cost-effective policies for management and monitoring of endangered populations or species are planned, knowledge of the spatial genetic structure and the type of population dynamics is of great concern. In this thesis the genetic diversity and population structures of two endangered arctic plant species was examined on different geographical scales in Northern Europe. The species were Siberian primrose (Primula nutans) and pendant grass (Arctophila fulva), which both grow in a seashore habitat and have similar distribution patterns on the shores of the Arctic Ocean and the Bothnian Bay. The goal of the present study was to provide basic population genetic information for the study species using microsatellite and AFLP markers. Both markers were used for the first time in these species, and species-specific microsatellite markers were developed during the study. A further aim was to interlink the population genetic processes of the species into distribution patterns at the regional and population levels and to compile a synthesis of the impact of hierarchical spatiotemporal processes and autocorrelation in genetic variation at different levels. The studies of this thesis provided new information on the diversity and population structure of the endangered study species and new markers that are useful in future genetic studies of primrose species. The diversity of Siberian primrose was low, and there was no dispersal between the study regions. In pendant grass, a relatively high amount of variation was found considering the evident clonal reproduction and gene flow that was detected between populations connected by waterways. The results suggested that both clonal and sexual reproduction are important in this species. On a local scale, pendant grass populations had characteristics of “stepping stone” and classical metapopulation models. The results indicated that on a long time scale, both species will continue to decline without efficient management efforts. Most critical for the persistence of the species is the conservation of suitable habitats. Translocations could be considered in order to enhance the diversity of existing populations and establish new populations. By examining the present day structure of Siberian primrose, it was possible to make inferences regarding the colonisation history of the species in the North European area. The current distribution of Siberian primrose seemed to result from a vicariant process that took place after the last ice-age, when the species colonised the area. It spread first to the White Sea area, probably from the east, and subsequently colonised the Bothnian Bay and the Barents Sea in the west. The isostatic land uplift after the retreat of the Eurasian ice sheet uncovered large areas of land from the Baltic Sea basin that previously were under water. These geological changes resulted in the current disjunct distribution of Siberian primrose.

Gopher tortoise (Gopherus polyphemus) population sizes have drastically declined in the past 100 years. Much of this decline has been attributed to past human predation, to habitat loss from human development, and potentially to the recently discovered upper respiratory tract disease. An understanding of the genetic structure among populations is critical for the long-term success of relocation and other management strategies. This research focuses on the development of a suite of genetic markers and the answers they provided to questions concerning present day population genetics and its use in management. In addition, this study provides inference on historical refugia and dispersal patterns of the gopher tortoise through the Pleistocene. Nine microsatellite loci were identified, optimized, and characterized from a G. polyphemus microsatellite-enriched DNA library. These loci are applicable for population level analysis along with parentage analysis in all Gopherus species. In addition, a few of the loci also work in other Testudinies. Application of these markers to eighteen Florida and two Georgia populations of gopher tortoises reveal considerable amount of genetic diversity within the species and substantial genetic subdivision among populations, especially in the northern part of the Florida peninsula and southern Georgia. Admixture and genetic homogenization in central Florida may be attributed to past human mitigation events as much of this area has been substantially developed. These data indicate a more conservative approach to relocation is necessary if the goal is to maintain the genetic distinctiveness of these areas. Lastly, these genetic data, in conjunction with historical geological, climactic, and fossil records, were used to identify gopher tortoise refugia, and dispersal patterns during the Pleistocene. Within Florida, four major genetic assemblages were determined that correspond to four Pleistocene ridges that would have been present at high sea levels: Lake Wales Ridge, Brooksville Ridge, Southern Atlantic Coastal Ridge, and Mt. Dora Ridge. In addition, these data indicate that tortoises that dispersed into southeastern Florida after the fall in sea level were most closely related to tortoises from the Brooksville Ridge. Likewise, tortoises in northwestern Florida and southern Georgia were most closely related to tortoises from the Mt. Dora Ridge.

No description available.

Conservation genetics for endangered species is crucial in long-term conservation actions.Inbreeding depression and genetic diversity are main genetic parameters with relevance toconservation. The Iberian lynx was by 2002 the most endangered felid in the world. Manyconservation programs have been carried out during the last 20 years, greatly improving theoutlook of the species. There is a paucity of information on the genetic consequences of thereintroduction program thus far. In the following research study, the most endangered Iberianlynx population, the Doñana population, is assessed to determine its actual genetic status andevaluate the genetic consequences of translocations initiated in 2007. This was achieved by thereconstruction of the pedigree of the wild population, and molecular analysis based on genotypedata with the use of Single Nucleotide Polymorphisms (SNPs). The molecular parameterscalculated were inbreeding coefficients, ancestry and genetic diversity. Results show an increase ingenetic diversity and a decrease in inbreeding following translocations. Post translocationinbreeding was found and explained by ancestral classes the individuals belonged to. These resultslay foundation for the importance of the ongoing translocations within the population andemphasize the need in the coming years for the conservation efforts carried out so far.

No description available.

No description available.

Landscape genetic approaches allow to study effects of landscape to population microevolution. Landscape can influence gene flow even in large carnivores with good dispersal ability. Understanding the influence of landscape to the gene flow between populations is crucial for species conservation, especially in the species with low population densities. Aim of the study was to describe genetic structure of the grey wolf (Canis lupus) and snow leopard (Panthera uncia) in selected areas and to determine the influence of the landscape features on observed structure. Non-invasive genetic samples of snow leopard from Nepal were analysed, as well as invasive and non-invasive samples of grey wolf from Central Europe. Population structure was determined a posteriori using Bayesian clustering approaches that integrate genetic and geographical data, and compared to landscape connectivity models. Population structure of snow leopards is mostly influenced by human presence and presence of frequented roads, which represent a substantial dispersal barrier. Habitat suitable for this species is greatly restricted by altitude, however, during dispersal they are able to overcome areas with higher elevation than what is optimal for them. Pronounced genetic difference was found between central European and Carpathian...

Made available in DSpace on 2016-08-10T10:55:06Z (GMT). No. of bitstreams: 1 Nicole Cristina Lopes Dutra.pdf: 1587085 bytes, checksum: 7c8f39f69da6456b027da52bf00a0794 (MD5) Previous issue date: 2006-11-29 / Studies that concern Cerrado (Brazilian s Savannah) fauna are important as we consider the elevated rate of destruction of its landscapes in the last decades. Bothrops moojeni is one of the species of vipers that occur on the Cerrado area and its venom has shown great applicability in health. In the last years, molecular markers have helped in researches that aim to assess the genetic variability. In the present work, we perform the characterization of 5 populations of Caiçaca (Bothrops moojeni) using RAPD (Random Amplified Polimorphyc DNA) markers and also used a scienciometric approach to highlight the importance of this species in health in the site Institute for Scientific Information (ISI), using the method General Search with the key words: serpente , Bothrops and Bothrops moojeni . The obtained Data were used to estimate the magnitude and distribution of variability within and among the groups using AMOVA. Aiming to analyze the patterns of spatial variation patterns, Pearson relation coefficient (r) was estimated between the matrixes of genetic distances and geographic among the populations. With the 5 primers were obtained 59 loci, from which 81 porcent (48) were polymorphic, ranging between 35% and 69% in the groups. The value of f ST obtained with AMOVA was equal to 0,13 (P smaller 0,0001 - 10000 permutations). Thus, it was possible to observe that Caiçaca populations studied presented a low level of genetic variability (He = 0,19) and most of the genetic variation is within the populations, what might indicate that is already occurring a reduction of the rate of gene flow between the populations. Considering the geographic area studied (lager distance was equal to 851,83 km), populations that are geographically near presented a high level of genetic diversity and the genetic variability is not spatially structured. The populations of Bothrops moojeni studied presented low levels of Genetic diversity for the RAPD loci evaluated. Genetic variability is not spatially structured. Concerning scienciometry analyses, the following key-words: serpente , Bothrops and Bothrops moojeni most of the studies concerning zoology (51 porcent), Pharmacology and Pharmacy (32 porcent) and Biochemistry and Molecular Biology (23 porcent), there was no paper published till the present date, that aimed to evaluate genetic variability in this species, as well as in the genus Bothrops. We recommend a wide-ranging study to evaluate genetic variability in this species due to its importance to conservation of the ecosystem from which it belong as well due to the great interest in health. / Estudos sobre a fauna do Cerrado são importantes considerando a alta taxa de destruição das suas paisagens naturais durante as últimas décadas. Estudos com marcadores moleculares se fazem importantes, pois auxiliam nas pesquisas que pretendem acessar a variabilidade genética para fins de conservação. Entre as espécies do Cerrado, Bothrops moojeni é uma serpente que vem demonstrando grande aplicabilidade na saúde. Neste sentido, o objetivo deste trabalho foi caracterizar a variabilidade genética de cinco populações de Caiçaca (Bothrops moojeni Hoge, 1966) a partir de marcadores RAPD (Random Amplified Polimorphyc DNA), bem como realizar um levantamento cienciométrico da importância da espécie para a área da saúde no sítio Institute for Scientific Information (ISI), utilizando o método GeneralSearch com a palavras chaves: serpentes, Bothrops e Bothrops moojeni. Os dados gerados com marcadores RAPD foram utilizados para avaliar a magnitude e a distribuição da variabilidade entre e dentro das populações por meio da Análise de Variância Molecular (AMOVA). A fim de se avaliar os padrões de variação espacial, foi estimado o coeficiente de correlação de Pearson (r) entre a matriz de distâncias genéticas e geográficas entre as populações. Com base nos cinco primers foram obtidos 59 locos, dos quais 81 por cento (48) foram polimórficos, variando entre 35 por cento e 69 por cento nas populações. O valor do Fí ST obtido pela AMOVA foi igual a 0,13 (P menor 0,0001 - 10000 permutações). Foi possível observar que as populações de Caiçaca estudadas apresentam baixos níveis de variabilidade genética (He = 0,19) para os locos RAPD estudados, sendo que a maior parte da variação encontra-se dentro das populações, o que poderia indicar que já está ocorrendo uma redução na taxa de fluxo gênico entre as populações. Considerando a escala geográfica em estudo (maior distância igual a 851,83 km), populações que estão próximas geograficamente apresentam uma considerável divergência genética e a variabilidade genética não se encontra estruturada espacialmente. No que diz respeito a cienciometria, nas palavras-chave serpente , Bothrops e Bothrops moojeni a maioria dos estudos foi sobre zoologia (51 por cento), Farmacologia e Farmácia (32 por cento) e Bioquímica e Biologia Molecular (23 por cento), não existindo nenhum trabalho publicado, até a presente data, que avalie a variabilidade genética desta espécie. Deve-se proceder com uma análise mais sistemática e de maior magnitude para avaliar a variabilidade genética desta espécie que além de sua importância para a conservação é uma espécie de muito interesse para a área de saúde.

Despite a thorough understanding of the proximate mechanisms that drive genetic diversity, we are still very poor at predicting the genetic diversity of natural populations. Understanding patterns of genetic diversity is important for many reasons, including predicting species' adaptation to climate change and predicting the spread of invasive species, but it is particularly important for species that are declining. This dissertation attempts to explain patterns in genetic diversity at multiple spatial scales across the range of the Northern Leopard Frog, Rana pipiens, which is declining across large portions of its range. Genetic diversity is often lower in edge populations than in central populations. Genetic diversity may be reduced in edge populations per se, or populations that occur at the edge of the species' range may have low diversity because they have recently expanded into new habitat and thus show signs of founder effects. In Chapter 2, we tested several alternative hypotheses to explain genetic diversity across the species' range, and to explain why some edge populations may not show reduced genetic diversity. We found that genetic diversity was reduced in edge populations relative to central populations, but was not reduced in populations in previously glaciated areas relative to previously unglaciated areas; therefore position at range edge had a stronger effect in reducing diversity than recent colonization of new habitat. We found that genetic diversity declined linearly towards the range edge in one of two transects from range center to range edge. We concluded that genetic diversity in this species is generally reduced by position at the range edge, but that this effect may differ among edges. In Chapter 3, we tested the hypothesis that eastern and western populations were genetically distinct. We found two distinct clades that introgress in some markers but are distinct and defined by narrow boundaries in the eastern Great Lakes region in others. We concluded that genetic diversity in the Mississippi River region was elevated by the introgression of descendants from two Pleistocene refugia. In Chapter 4, we analyzed genetic diversity within populations throughout Arizona to assess potential source populations for reintroductions. We also analyzed mitochondrial DNA to determine whether any populations contained genetic material not native to the region. Populations in one area had high genetic diversity and high gene flow among populations, but also contained evidence of introduction of eastern frogs. We conclude that supplementing genetic diversity in other populations with translocations from this area is not recommended.

Genes are the foundation of evolution and biodiversity. The genetic structure of natural populations needs to be understood to maintain exploited resources rationally. This thesis focuses on genetic variability and methods to determine spatial and temporal genetic heterogeneities. Intense human exploitation generates particular challenges to conserve genetic diversity of fishes since it has genetic effects. My research concerns one of our most valuable fish species: the Atlantic herring (Clupea harengus). I analyzed Atlantic herring samples from the North and Baltic Seas. The objectives were to determine: 1) spatial genetic structure, 2) whether allozymes and microsatellites provide similar descriptions of the differentiation pattern, or 3) if they are influenced by selection, 4) factors affecting statistical power when testing for genetic differentiation, and 5) the temporal stability of the genetic structure. The results show: 1) very low levels of spatial genetic differentiation in Atlantic herring; a major component is a difference between the Baltic and North Seas, 2) a concordant pattern with allozymes and microsatellites, 3) that selection influences a microsatellite locus, which can be a low salinity adaptation, 4) that statistical power is substantial for frequently used sample sizes and markers; the difference in power between organelle and nuclear loci is partly dependent on the populations’ stage of divergence, and 5) no changes in amount of genetic variation or spatial genetic structure over a 24-year period; the selection pattern in one microsatellite locus remained. The notion that the large population sizes make herring unlikely to lose genetic diversity may be disputed. I found small local effective population sizes, and the evidence of selection hints of a distinct evolutionary lineage in the Baltic. When Atlantic herring is managed as very large units, there can be detrimental genetic effects if certain population segments are excessively harvested.