Sökning: "Staffan Bensch"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Staffan Bensch.

  1. 1. Genetics and the Origin of Two Flycatcher Species

    Författare :Thomas Borge; Glenn-Peter Saetre; Staffan Bensch; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; reinforcement; reproductive isolation; Z chromosome; hybridization; mate-choice; single nucleotide polymorphism; sequence variation; sexual selection; recombination; Biologi; Biology; Biologi;

    Sammanfattning : In this thesis, different genetic tools are used to investigate pre- and postzygotic barriers to gene exchange and their role in speciation in the pied flycatcher (Ficedula hypoleuca) and the collared flycatcher (F. albicollis). This species complex consists of four genetically distinct clades that apparently diverged in allopatry (I). LÄS MER

  2. 2. Population Genetic Structure of Black Grouse (Tetrao tetrix) : From a Large to a Fine Scale Perspective

    Författare :Carolina Corrales Duque; Jacob Höglund; Staffan Bensch; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; black grouse; control region; demographic expansion; kin selection; lek; microsatellites; non-invasive sampling; postglacial colonisation; philopatry; phylogeography; sex-biased dispersal; spatial genetics; subspecies; suture zone; refugia; Biology; Biologi; Systematics and phylogenetics; Systematik och fylogeni; Biologi med inriktning mot populationsbiologi; Biology with specialization in Population Biology;

    Sammanfattning : Black grouse (Tetrao tetrix) is a bird species with a lek mating system found in the Palearctic boreal taiga. It is assumed that it has a continuous distribution along Scandinavia and Siberia, whereas in Central Europe it has declined during the last decades. LÄS MER

  3. 3. On the Effects of Blood Parasites in Wild Birds

    Författare :Peter Halvarsson; Jacob Höglund; Staffan Bensch; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Atoxoplasma; avian malaria; coccidia; Gallinago media; Haemoproteus; Leucocytozoon; parasite prevalence; Passer montanus; Plasmodium; recapture mod-els; survival; Biologi med inriktning mot populationsbiologi; Biology with specialization in Population Biology;

    Sammanfattning : Coccidian and haemoatozoan parasites are commonly occurring endo-parasites in wild birds and prevalence can vary among species and populations. In addition to prevalence studies, parasites are often used to investigate effects on life history traits. LÄS MER

  4. 4. Animal movement on short and long time scales and the effect on genetic diversity in cold-adapted species

    Författare :Vendela Kempe Lagerholm; Love Dalén; Anders Angerbjörn; Bensch Staffan; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : The genetic diversity in modern species is strongly affected by contemporary gene flow between populations, which in turn is governed by individual dispersal capacities and barriers in the landscape. However, current patterns of variation have also been shaped by movement over longer time-scales, such as the successive shifts in species distributions that have occurred during past climate changes. LÄS MER

  5. 5. Hybrid zone dynamics, assortative mating, and migratory programmes in a willow warbler migratory divide

    Författare :Keith W. Larson; Susanne Åkesson; Staffan Bensch; Martin Schaefer; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; migratory divide; phenotype; willow warbler; hybrid zone; tension zone; Phylloscopus trochilus; migratype; assortative mating; migration; biology; biologi; evolutionär genetik; evolutionary genetics; migratory divide; phenotype; willow warbler; hybrid zone; tension zone; Phylloscopus trochilus; migratype; assortative mating; migration;

    Sammanfattning : In this thesis I will compare and contrast the two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) with differing migratory phenotypes (or "migratype") in the context of their migratory divide and hybrid zone in central Sweden. Their migratory programs differ in the direction and distance traveled during migration. LÄS MER