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Visar resultat 16 - 19 av 19 avhandlingar som matchar ovanstående sökkriterier.

  1. 16. Clades in the "higher land bird assemblage"

    Författare :Ulf. S. Johansson; Scott V. Eswards; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Birds; Fåglar; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : This thesis summarizes the results of several phylogenetic studies of birds included in the “higher land bird assemblage” (Anomalogonatae sensu Beddard 1898). The phylogenetic analyses are primarily based on gene sequences obtained from the nuclear genome (exons of the c-myc and RAG-1 genes and an intron of the myoglobin gene). LÄS MER

  3. 17. Comparative morphological studies of fossil and living plane trees (Platanaceae) and oaks (Quercus): taxonomy, ecology, evolution

    Författare :Georg Florian Tschan; Thomas Denk; Ove Eriksson; Bertil Ståhl; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Platanaceae; Platanus; Credneria; Quercus; Galliferae; leaf architecture; epidermal anatomy; comparative morphology; character variation; variability; sample size; diversity patterns; species concepts; ecology; biogeography; evolution; plant fossils; Plant Ecology; växtekologi;

    Sammanfattning : Morphological characters are essential for flowering plant identification, but also provide information about diversity patterns and ecological adaptation. In woody plant species, characters of the leaf are among the most useful and can be examined on fossils as well. LÄS MER

  4. 18. Evolutionary studies of the Gnetales

    Författare :Chen Hou; Catarina Rydin; Richard Saunders; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; växtsystematik; Plant Systematics;

    Sammanfattning : The Gnetales consist of three distinct genera, Ephedra, Gnetum and Welwitschia with considerable divergence among them regarding morphological, ecological and molecular characters. A longstanding debate of the similarity between the Gnetales and angiosperms and the unresolved seed plant phylogeny intrigues plant scientists to further investigate the evolutionary history of the Gnetales. LÄS MER

  5. 19. Tectonic Evolution of the Zagros Suture-and Imbricate Zones in Iraq

    Författare :Maher T. Zainy; Maria Ask; Francisco Gomez; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tectonic evolution; Zagros Fold-and Thrust Belt; Remote sensing; Field feological work; 3D geological modelling; Natural resources exploration; Applied Geology; Tillämpad geologi;

    Sammanfattning : Orogenic belts are expressions of tectonic activity, often host various natural resources (e.g. petroleum and minerals reserves), and influence the society and environment through hazards (e.g. LÄS MER