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Visar resultat 21 - 25 av 144 avhandlingar som matchar ovanstående sökkriterier.

1. 21. Hybrid zones and speciation – insights from the European crow hybrid zone

   Författare :Fredrik Haas; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; microsatellites; mc1r; introgression; hybrid zone; speciation; European crow; Corvus corone; habitat preferences; neural network; sexual imprinting; assortative mating;

   Sammanfattning : In hybrid zones genetically differentiated populations meet and interbreed. As they result from ongoing divergence and potential speciation, such zones provide opportunities to study how different factors affect this process. The hybrid zone between the all black carrion crow (Corvus corone corone) and the grey and black hooded crow (Corvus c. LÄS MER

3. 22. Evolutionary Processes and Hybridization within the Peat Mosses, Sphagnum

   Författare :Rayna Natcheva; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; taxonomi; morfologi; kemotaxonomi. Växters fysiologi inte kärlväxter .; Sphagnum; bryophytes; morphology; phytogeography; chemotaxonomy. Physiology of nonvascular plants; Systematisk botanik; growth rate; regeneration; evolution; Systematic botany; taxonomy; introgression; maternal inheritance; recombination; hybridizarion;

   Sammanfattning : The aim of this thesis was to reveal details of the interspecific hybridization among bryophytes as exemplified by Sphagnum capillifolium and S. quinquefarium. LÄS MER

4. 23. Genetic Identification of Corkwing Wrasse Cleaner Fish Escaping from Norwegian Aquaculture

   Författare :Ellika Faust; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Conservation; Population structure; Genetics; Aquaculture; Hybridization; Corkwing wrasse; Cleaner fish; Sea lice; Symphodus melops; Escapee; Range expansion;

   Sammanfattning : The genetic impact of farmed fish escaping aquaculture is a highly debated issue. However, non-target species, such as cleaner fish that are used in fish farms to remove parasitic sea lice, are rarely considered. LÄS MER

5. 24. Predation as a driver of reproductive isolation - from adaptive divergence to hybrid inviability

   Författare :Varpu Pärssinen; Enhet akvatisk ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; reproductive isolation; ecological speciation; predation; adaptive radiation; evolution; behaviour; fish;

   Sammanfattning : Natural selection can play an important role in the origin of new species. When reproductive isolation evolves as a result of ecologically-based divergent natural selection, the process is referred to as ecological speciation. In most organisms, sufficient reproductive isolation is considered to be essential for the establishment of new species. LÄS MER

7. 25. Hybridisation between introduced brown hares and native mountain hares in Sweden

   Författare :Carl-Gustaf Thulin; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; naturvårdsbiologi; Conservation Biology;

   Sammanfattning : To investigate the extent and effect of hybridisation between wild sympatric populations of introduced brown hares (Lepus europaeus) and native mountain hares (L.timidus) in Sweden, the geographic distribution of genetic variation in mitochondrial DNA (mtDNA) and nuclear DNA microsatellite markers were analysed within and between the two species and their presumed hybrids. LÄS MER