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Visar resultat 1 - 5 av 1349 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Integrative taxonomy of birds : Studies into the nature, origin and delimitation of species

    Författare :George Sangster; Per G. P. Ericson; Martin Päckert; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Aves; biogeography; integrative taxonomy; pluralism; ring species; speciation; species criteria; species limits; taxon chain; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Species are the basic currency in biodiversity studies but what constitutes a species has long been controversial. A major breakthough was the insight that most systematists agree that species are segments of population lineages, and that multiple lines of evidence should be employed and integrated, a procedure called integrative taxonomy. LÄS MER

  2. 2. Climbing the Trichoptera Tree : Investigations of Branches and Leaves

    Författare :Tobias Malm; Kjell Arne Johanson; Wolfram Mey; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Trichoptera; Leptoceridae; Symphitoneuria; Gracilipsodes; Triplectides; morphology; DNA; systematics; phylogeny; New Caledonia; Madagascar; new species; new genus; Systematics and phylogenetics; Systematik och fylogeni; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : The Trichoptera (caddisflies) is the largest of the primary aquatic insect orders, currently including more than 13,500 species. With more than 100 species new to science described annually, the known caddisfly diversity is rapidly increasing. In the first four papers of this Thesis, a total of 22 species new to science are described. LÄS MER

  3. 3. Diversification on an ancient Darwinian island : Evolutionary history of caddisflies (Trichoptera) and other organisms on New Caledonia

    Författare :Marianne Espeland; Kjell Arne Johanson; Niklas Wahlberg; Michael Balke; Stockholms universitet; []
    Nyckelord :New Caledonia; Trichoptera; island; biogeography; phylogenetics; DNA; dispersal; vicariance; adaptation; ultramafic; diversification; new species; environmental factors; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Islands are either of continental or oceanic origin, and the biota of such islands are a result of vicariance and dispersal, respectively. New Caledonia, in the South Pacific, is a part of former Gondwana, but the origin of its biota is heavily debated. LÄS MER

  4. 4. 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

  5. 5. Through the magnifying glass - The big small world of marine meiofauna : Morphology, species and evolution in Nemertodermatida

    Författare :Inga Meyer-Wachsmuth; Ulf Jondelius; Mark E Sidall; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nemertodermatida; Acoelomorpha; morphology; CLSM; Phalloidin; musculature; DNA; cryptic species; species delimitation; dispersal; taxonomy; phylogenetics; IHC; nervous system; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Nemertodermatida is a group of microscopic marine worm-like animals that live as part of the marine meiofauna in sandy or muddy sediments; one species lives commensally in a holothurian. These benthic worms were thought to disperse passively with ocean currents, resulting in little speciation and thus wide or even cosmopolitan distributions. LÄS MER