Search for dissertations about: "phylogenetic network"

Showing result 1 - 5 of 17 swedish dissertations containing the words phylogenetic network.

  2. 1. Optimal and Hereditarily Optimal Realizations of Metric Spaces

    Author : Alice Lesser; Svante Janson; Lars-Erik Persson; Anders Johansson; Vincent Moulton; Pierre Flener; Charles Semple; Uppsala universitet; []
    Keywords : Applied mathematics; optimal realization; hereditarily optimal realization; tight span; phylogenetic network; Buneman graph; split decomposition; T-theory; finite metric space; topological graph theory; discrete geometry; Tillämpad matematik;

    Abstract : This PhD thesis, consisting of an introduction, four papers, and some supplementary results, studies the problem of finding an optimal realization of a given finite metric space: a weighted graph which preserves the metric's distances and has minimal total edge weight. This problem is known to be NP-hard, and solutions are not necessarily unique. READ MORE

  4. 2. Disentangling Lecania

    Author : Rikke Reese Næsborg; Leif Tibell; Stefan Ekman; Bengt Oxelman; Christian Printzen; Uppsala universitet; []
    Keywords : Biology; Crustose lichens; Phylogeny; Taxonomy; Morphology; New species; Phylogenetic diversity; Rare species; ITS; mt-SSU; RPB2; IGS; Biologi; Lecania; Ramalinaceae;

    Abstract : This thesis focuses on phylogenetic, taxonomic, ecological, and conservation aspects of the crustose lichen genus Lecania (Ramalinaceae, lichenized Ascomycota). Lecania has previously been defined on basis of relatively few morphological characters, and the genus had never been treated in molecular phylogenies. READ MORE

  5. 3. A forest dark : an evolutionary history of Norway spruce

    Author : Alexis R. Sullivan; Xiao-Ru Wang; Nathaniel Street; María Rosario García-Gil; Bengt Oxelman; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; phylogenetics; genome assembly; recombination; Picea; hybridization; mitogenome; Norway spruce; phylogeography; phylogenetic networks; plastome;

    Abstract : Embedded within the relationships among species is a dense forest of gene trees, each with a potentially unique and discordant history. Such widespread genealogical heterogeneity is expected, but embracing this hierarchy of discordance while reconstructing the histories of populations and species remains a major challenge. READ MORE

  6. 4. Phylogenetic Inference and Allopolyploid Speciation - A Study of Silene section Physolychnis

    Author : Anna Petri; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; allopolyploidization; next-generation sequencing; Physolychnis; sequence specific primers; Silene; species networks; transcriptomics;

    Abstract : The major theme of this thesis is allopolyploidization, with focus on Silene section Physolychnis. The evolutionary history of an allopolyploid species can be established by inferring the sister relationships of the homoeologous sequences from low copy nuclear markers. READ MORE

  7. 5. Phylogenetic perspective on host plant use, colonization and speciation in butterflies

    Author : Elisabet Weingartner; Sören Nylin; Niklas Wahlberg; Felix Sperling; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Oscillation hypothesis; speciation; Polygonia; Celastrina; Pararge; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; zoologisk ekologi; Animal Ecology;

    Abstract : In this thesis we have studied speciation in three butterfly genera Polygonia (Nymphalidae, Nymphalini), Pararge (Nymphalidae, Satyrinae) and Celastrina (Lycaenidae: Polyommatinae). In the first paper a dated phylogeny, based on molecular data, of Polygonia was constructed. We found strong conflict between the nDNA and mtDNA datasets. READ MORE