Sökning: "Speciation"

Visar resultat 6 - 10 av 282 avhandlingar innehållade ordet Speciation.

1. 6. Sex, Sperm and Speciation : On sexual selection and fertility in hybridizing flycatchers

   Författare :Murielle Ålund née Podevin; Anna Qvarnström; Simone Immler; Leonie Moyle; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sperm biology; sexual selection; speciation; hybridization; cryptic female choice; fertility; Ficedula flycatchers; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : Sexual reproduction entails complex co-evolution between the sexes, necessary for successful fertilization, ensuring individual and population-level fitness. Interfertility is the main criterion for species definition and understanding speciation requires detailed studies of reproductive barriers. LÄS MER

3. 7. Mechanisms of speciation in Silene

   Författare :Xiaodong Liu; Sophie Karrenberg; Alex Buerkle; Uppsala universitet; []
   Nyckelord :speciation; reproductive isolation; Silene; ddRAD-seq; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Sammanfattning : A fundamental question in the field of evolutionary biology is how new species originate. Investigating speciation benefits from an integrated approach, which requires a solid understanding of ecology, reproductive biology, geographical distribution, underlying genetic architecture of reproductive isolation (RI), demographic history and genomic divergence. LÄS MER

4. 8. Speciation genetics of recently diverged species

   Författare :Venkat Talla; Niclas Backström; Nicola Nadeau; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Speciation; Leptidea; Lepidoptera; chiffchaff; Cryptic species; genome-scan; Diapause; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Sammanfattning : Species differentiation can be a consequence of evolutionary forces including natural selection and random genetic drift. Patterns of genomic differentiation vary across the tree of life. This variation seems to be dependent on, for example, differences in genomic architecture and molecular mechanisms. LÄS MER

5. 9. Bottlenecks and blowflies : Speciation, reproduction and morphological variation in Lucilia

   Författare :Ann-Britt Florin; Lisa Meffert; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Population size; speciation; Lucilia sericata; morphological variation; Lucilia illustris; bottlenecks; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis attempts to improve our understanding of the role of population size for the process of speciation. First, the effect of population size on speciation is studied using several meta-analyses of published laboratory experiments. LÄS MER

7. 10. Metal Speciation and Toxicity in Sewage Sludge

   Författare :Annika Ekvall; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; partition coefficient; toxicity; speciation; sewage sludge; fractionation; metals;

   Sammanfattning : Increasingly stringent controls on metal concentrations in sewage sludge destined for agricultural application provided a basis for the study of the relevance of metal speciation in sewage sludge. A comprehensive literature review identified difficulties in relating metal speciation through single chemical extractions to plant uptake and soil toxicity. LÄS MER