Sökning: "habitat distribution"

Visar resultat 6 - 10 av 145 avhandlingar innehållade orden habitat distribution.

  1. 6. The evolutionary ecology of niche separation : Studies on the sympatric butterflies Leptidea sinapis and Leptidea reali

    Författare :Magne Friberg; Wiklund Christer; John N. Thompson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lepidoptera; ecological character displacement; reproductive isolation; species discrimination; habitat; host plant; life history; sexual selection; female choice; Biology; Biologi; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Studies of ecology and evolution have become largely integrated, and increasing attention is paid to the role of ecology for speciation and post speciation divergence. In this thesis I have applied an in-depth approach studying the ecology of a butterfly species pair; the morphologically virtually identical sister-species, the Wood white (Leptidea sinapis) and Reál’s wood white (Leptidea reali). LÄS MER

  3. 7. 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

  4. 8. Behavioural ecology of Indo-Pacific bottlenose and humpback dolphins

    Författare :Eva Stensland; Per Berggren; Anders Angerbjörn; Elisabeth Slooten; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Behaviour; ecology; dolphins; Zanzibar; abundance; distribution; tourism; mixed-species groups; interspecific association; social interaction; swim-with-dolphin; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : Dolphins in East Africa face various threats, such as direct hunt, bycatch and habitat degradation. It is therefore important to undertake research that can facilitate necessary conservation and management actions to minimize these threats. LÄS MER

  5. 9. Rarity in boreal stream: patterns, causes and consequences

    Författare :Per-Ola Hoffsten; Bo W. Svensson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Central Sweden; site occupancy; dispersal limitation; natural disturbances; recolonization; flight-morphology; metapopulation; habitat stability; spring specialists; Crunoecia irrorata; niche limitation; Isogenus nubecula; nestedness; longitudinal distribution; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; zooekologi; Animal Ecology;

    Sammanfattning : Patterns of site occupancy among boreal stream insects were studied in central Sweden with focus on sparsely distributed species and the role of dispersal and niche limitations.In the study of dispersal limitation, I found that effects of an extraordinarily harsh winter in small to medium-sized streams were strongest in sites located in small streams and far from lake outlets. LÄS MER

  7. 10. Phylogeny, taxonomy and species delimitation of water mites and velvet mites

    Författare :Jeanette Stålstedt; Johannes Bergsten; Fredrik Ronquist; Joanna Mąkol; Ashley Dowling; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Acariformes; Parasitengona; Hydrachnidia; Trombidia; water mites; velvet mites; taxonomy; cryptic species; species delimitation; DNA; GMYC; experimental rearing; new synonyms; distribution; phylogeny; revised classification; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : This study is part of the Swedish Taxonomy Initiative (STI) - one of the most ambitious all taxa biodiversity inventories in the world. One of the pillars in STI is to support taxonomic research on the most neglected taxonomic groups with the aim to lift the level of knowledge of biodiversity in the country. LÄS MER