Sökning: "isolated population"

Visar resultat 1 - 5 av 295 avhandlingar innehållade orden isolated population.

  1. 1. Genomics of population decline

    Författare :Tom van der Valk; Katerina Guschanski; Aylwyn Scally; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; genetic diversity; minimal-invasive samples; population decline; inbreeding; genetic purging; eastern gorillas; Dryas monkey; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

    Sammanfattning : With human populations forecasted to grow in the next decades, many mammals face increasing anthropogenic threats. The consequential population declines are a precursor to extinctions, as small populations are not only more sensitive to stochastic events, but reduction in population size is generally also followed by a decrease in genetic diversity, which in turn reduces adaptive potential and fitness of the population. LÄS MER

  2. 2. Population size and genetic diversity of Nigerian lions (Panthera leo)

    Författare :Talatu Tende; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; non-invasive sampling; faecal DNA; protected area; isolated population; Panthera leo;

    Sammanfattning : High growth rate in human populations, agricultural developments and industrialization have impinged negatively on the natural habitats of most large carnivores, causing fragmentation, isolation and consequently reduction in population size. Lions (Panthera leo) that once roamed most parts of Southern Europe, Asia, the Middle East, North America, northern part of South America and most parts of Africa are today found only in parts of sub-Saharan Africa and at a single site in India. LÄS MER

  3. 3. Population History and Non-invasive Monitoring : Use of low copy number DNA in Conservation Genetics

    Författare :Øystein Flagstad; Ettore Randi; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; genetic tagging; immigration; loss of genetic variability; non-invasive molecular techniques; population decline; Swayne’s hartebeest; wolf; wolverine; Biologi; Biology; Biologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Conservation genetics research is increasingly becoming an integrated part of the management of small and endangered populations. In this thesis I developed tools for genetic analysis of low copy number sources of DNA, such as old teeth from museum specimens as well as field-collected faeces and urine. LÄS MER

  4. 4. Population Dynamics and Conservation of the Sand Lizard (Lacerta agilis) on the Edge of its Range

    Författare :Sven-Åke Berglind; Pekka Pamilo; Per Sjögren-Gulve; Coulson Tim; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; demography; extinction; habitat; Lacerta agilis; management; metapopulation; peripheral populations; population dynamics; population viability analysis; reintroduction; reptiles; umbrella species; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : The sand lizard (Lacerta agilis) reaches the northern periphery of its distribution in south-central Sweden, where small, isolated relict populations occur in pine heath forests on sandy sediments. Modern forestry and fire suppression have reduced the amount of suitable open habitat for the species in this area and seem to be important for its decline. LÄS MER

  5. 5. Genomic analysis of the process leading up to the extinction of the woolly mammoth

    Författare :Patrícia Pečnerová; Love Dalén; Mark Thomas; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; woolly mammoth; Mammuthus primigenius; extinction; Wrangel Island; ancient DNA; palaeogenetics; population genetics; genomics; genomic erosion; genetic drift; inbreeding; population size; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Species worldwide are subject to contractions in both abundance and geographical range, and their persistence in a changing environment may thus depend on the ability to survive in small and fragmented populations. Despite the urgent need to understand how extinction works, our knowledge of pre-extinction genetic processes is limited because techniques allowing population and conservation genomics to be studied in wild threatened populations have become available only recently. LÄS MER