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Visar resultat 1 - 5 av 16 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Resource economy of carnivorous plants: Interactions between prey capture and plant performance in three subarctic Pinguicula species

    Författare :Magnus Thorén; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant ecology; income breeder; capital breeder; supplementary feeding; reproductive effort; life-history; cost of reproduction; Växtekologi;

    Sammanfattning : In this thesis, I have studied in situ the resource economy of the three carnivorous plant species Pinguicula alpina, P. villosa and P. vulgaris in a subarctic environment. The prey capture varied among individual plants, years and species. LÄS MER

  3. 2. Brood sex ratio and sex differences in Tengmalm’s owl : (Aegolius funereus)

    Författare :Tim Hipkiss; Gary Bortolotti; Umeå universitet; []
    Nyckelord :Aegolius funereus; avian CHD1 genes; brood sex ratio; differential mortality; nomadism; northern Sweden; sexual size dimorphism; sibling rivalry; supplementary feeding; vole cycles; zooekologi; Animal Ecology;

    Sammanfattning : Males and females differ in morphology and behaviour, so that selection acts differently on the two sexes. This changes the relative reproductive success of males and females, and it is beneficial for parents to bias the sex ratio of their broods in favour of the sex with the best survival and breeding prospects. LÄS MER

  4. 3. Omsorg om livet : Spädbarnsdödlighetens förändring i Ådalen under 1800-talet

    Författare :Stina Bohman; John Rogers; Rosemarie Fiebranz; Susanna Hedenborg; Uppsala universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Breast-feeding; demography; folklore; history; infant care; infant feeding; infant mortality; midwiwes; mothers; peasant society; physicians; sawmill; Sweden; women’s work; Ådalen; 19th century; History; Historia; Historia; History;

    Sammanfattning : During the first half of the nineteenth century infant mortality rates in Ådalen, an agrarian region in northern Sweden, were among the highest in the country. During the second half of the century the region experienced a rapid population growth and a restructuring of the economy in conjunction with the expansion of the sawmill industry. LÄS MER

  5. 4. Weaned Upon A Time : Studies of the Infant Diet in Prehistory

    Författare :Rachel Howcroft; Kerstin Lidén; Gunilla Eriksson; Tamsin O'Connell; Stockholms universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Infant Feeding; Breastfeeding; Weaning; Milk; Diet; Fertility; Neolithic; Agriculture; Hunter-Gatherer; Bronze Age; Iron Age; Prehistory; Carbon and Nitrogen Stable Isotope Ratios; Bone; Dentine; Archaeological Science; laborativ arkeologi;

    Sammanfattning : This thesis is concerned with how prehistoric infants were fed in different physical and cultural environments, and in particular what impact the economic, social, and epidemiological changes associated with the development of agriculture had on infant feeding practices. In order to examine these effects, stable isotope ratio analysis has been used to assess the duration of breastfeeding and weaning in a variety of prehistoric contexts. LÄS MER

  7. 5. Indirect effects of moose on the birds and the bees

    Författare :Karen Marie Mathisen; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Large herbivores are important drivers of ecosystem processes, affecting plant species richness and composition, primary productivity, habitat structure as well as nutrient cycling. Large herbivore activities may therefore have important indirect effects on other plants and animals in the same ecosystem. LÄS MER