Sökning: "systematik"

Visar resultat 21 - 25 av 128 avhandlingar innehållade ordet systematik.

  1. 21. Tubificids with trifid chaetae: morphology and phylogeny of Heterodrilus (Clitellata, Annelida)

    Författare :Erica Sjölin; Christer Erséus; Lena Gustavsson; Mari Källersjö; Katrine Worsaae; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Heterodrilus; phylogeny; morphology; Tubificidae; Systematics and phylogenetics; Systematik och fylogeni; Systematic Zoology; systematisk zoologi;

    Sammanfattning : Heterodrilus is a marine group of small (3-25 mm) clitellates that occur interstitially in sandy sediments from the intertidal zone down to about 150 m depths. The taxon includes 42 valid species and has been recorded from localities in the Mediterranean Sea, the North-west Atlantic Ocean (including the Caribbean), the Galapagos Islands, and the Indo-Pacific Region. LÄS MER

  2. 22. Phylogenetic and taxonomic studies within Arthonia Ach. (Ascomycetes, Arthoniales)

    Författare :Rikard Sundin; Jan-Eric Mattsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systematics and phylogenetics; Systematik och fylogeni; Plant Systematics; växtsystematik;

    Sammanfattning : The taxonomy and phylogeny of the genus Arthonia was analysed. As a first step, a phylogenetic analysis was performed to test the monophyly of some of the infrageneric groups suggested by earlier authors. The results strongly support that Arthonia, Arthothelium and Arthoniaceae are paraphyletic. LÄS MER

  3. 23. The Dawn of a New Age : Interrelationships of Acoela and Nemertodermatida and the Early Evolution of Bilateria

    Författare :Andreas Wallberg; Ulf Jondelius; Mikael Thollesson; Graham Budd; Gonzalo Giribet; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Acoela; Nemertodermatida; Bilateria; Metazoa; evolution; phylogenetic inferrence; ancestral reconstruction; taxon sampling; microRNA; Systematics and phylogenetics; Systematik och fylogeni; systematisk zoologi; Systematic Zoology;

    Sammanfattning : Deciphering the rapid emergence of bilaterian animals around the time of the Cambrian Explosion and reconstructing the interrelationships of animal groups have long been two of the most elusive problems in Zoology. This thesis concerns the phylogenetic interrelationships within and among Acoela and Nemertodermatida, two groups of small worms that are believed to be basal bilaterians and which may provide important clues for understanding the early evolution of animals. LÄS MER

  4. 24. Babblers, Biogeography and Bayesian Reasoning

    Författare :Magnus Gelang; Per Ericson; Per Alström; Isabel Sanmartín Bastida; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Africa; Asia; Bayesian inference; biogeography; Cettidae; dispersal; extinction; Middle East; persistence; Sylvioidea; Sylviidae; Timaliidae; vicariance; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : In this thesis, I try to proceed one step further towards an understanding of the biogeographic processes forming the distribution patterns of organisms that we see today. Babblers and warblers are diverse groups of passerines that are phylogenetically intermixed with other groups in the superfamily Sylvioidea. LÄS MER

  5. 25. Charting biodiversity : Scuttle flies and other poorly known insects in Sweden

    Författare :Sibylle Häggqvist; Fredrik Ronquist; Jeff Skevinton; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Biodiversity has fascinated people in all times. We as a species are part of the global ecosystem and our survival depends on many other species around us. Charting biodiversity, however, has proven more difficult than one could imagine. LÄS MER