Sökning: "incomplete lineage sorting"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden incomplete lineage sorting.
1. Disentangling the Reticulate History of Polyploids in Silene (Caryophyllaceae)
Sammanfattning : DNA sequences from the rps16 intron and the psbE-petL spacer from the chloroplast genome, the ribosomal nuclear ITS region, and introns from the low copy nuclear genes RPA2, RPB2, RPD2a and RPD2b, are in different combinations used to infer phylogenetic relationships in Sileneae (Caryophyllaceae). Used in concert, the biparentally inherited nuclear regions are useful to distinguish between paralogy due to allopolyploidy and single gene duplications, respectively, because the latter are not expected to give rise to repeated phylogenetic patterns in potentially unlinked sequence regions. LÄS MER
2. Next-generation Molecular Systematics and Evolution: insights into Medicago
Sammanfattning : Evolutionary relationships among species have in recent years been inferred using DNA sequences from specific genes and represented by tree diagrams (phylogenies). However, the signal contained in different genes can produce conflicting sets of relationships – i.e., gene tree incongruence. LÄS MER
3. Phylogeny and topological incongruence in the Rubioideae (Rubiaceae)
Sammanfattning : The work with this thesis has focused on evolutionary relationships in the Rubioideae, the most species-rich subfamily of the large and diverse coffee family (Rubiaceae). Despite considerable efforts during the last decades, uncertainty regarding several relationships in this group has remained, either as a result of unconvincing statistic support, incongruent results, or insufficient taxon sampling. LÄS MER
4. Bridging the past to the present: investigating species boundaries with herbarium specimens and next-generation-sequencing. A case study of circumpolar Silene sect. Physolychnis
Sammanfattning : During the recent decades, genetic information enclosed in herbarium collections have been partly revealed, largely due to the fast-moving high-throughput sequencing technologies. However, the genetic outcome from herbarium material is limited by its degradation over time, often worsened by certain preservation methods. LÄS MER
5. The evolution of flat periwinkles Littorina fabalis and L. obtusata emhasizing mitochondrial introgression and restricted recombination
Sammanfattning : The evolution of species takes in general very long time and different mechanisms are likely to operate during the various stages of this process. Accordingly speciation should be studied at different levels of species divergence. LÄS MER