Sökning: "life history evolution"

Visar resultat 6 - 10 av 115 avhandlingar innehållade orden life history evolution.

  1. 6. Life history evolution in a bivoltine butterfly

    Författare :Helena Larsdotter Mellström; Christer Wiklund; Klaus Fischer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bivoltine; Diapause; Lepidoptera; Life history; Mating system; Pheromone; Polyphenism; Population density; Sexual selection; Sperm competition; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Evolution is not always straight-forward, as selection pressures may differ between different generations of the same species. This thesis focuses on the evolution of life history of the model species, the Green-veined White butterfly Pieris napi. In central Sweden P. napi has two generations per year. LÄS MER

  3. 7. Mwalimu och Ujamaa : Julius Karambage Nyerere och nationsbildningen i Tanzania

    Författare :Olof Lönneborg; Umeå universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Africa; nation-building; Nyerere; Tanzania; Catholic social teaching; Fabian Society; African Socialism; African Personality; ujamaa; development; democratization; communitarianism;

    Sammanfattning : The present study is a political biography in the broad sense of Julius Karambage Nyerere. The main perspective has been his significance for nation-building in Tanzania. The dissertation is chronologically ordered after his life and restricted to the period 1922-1977. LÄS MER

  4. 8. Age-specific trade-offs in life-history evolution

    Författare :Martyna K. Zwoinska; Alexei Maklakov; Marjo Saastamoinen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; life history; trade-off; learning; aging; sex differences; dispersal; Caenorhabditis; Drosophila; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

    Sammanfattning : Trade-offs prevent selection from driving all fitness-enhancing traits towards values that would maximize fitness. Life-history trade-offs, such as the one between survival and reproduction are well-studied, yet trade-offs can also involve behavioural or cognitive traits. LÄS MER

  5. 9. Life history evolution during a climate-driven butterfly range expansion

    Författare :Mats Ittonen; Karl Gotthard; Philipp Lehmann; Christopher Wheat; Sarah Diamond; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; climate change; diapause; genomics; insect cold tolerance; life cycle; local adaptation; parallel evolution; photoperiodism; reciprocal transplant; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Climate change pushes species polewards and upwards – as temperatures rise, species move to areas that were previously too cold for them. During range expansions, species encounter unfamiliar environmental conditions, which may require evolutionary adaptation, but expanding populations may often be hampered by their genetic and demographic properties. LÄS MER

  7. 10. Biotic and abiotic drivers of life-history and demographic variation in boreal orchids

    Författare :Matthew R. Tye; Nina Sletvold; Yvonne Buckley; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant demography; life-history; climate; pollination; compensation; orchids; resources; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Sammanfattning : Environmental interactions, including both abiotic and biotic factors, are key drivers of life-history and population dynamics. Despite this, most population studies do not explicitly link variation in environmental factors and vital rates. LÄS MER