Sökning: "reproductive success"

Visar resultat 21 - 25 av 123 avhandlingar innehållade orden reproductive success.

  1. 21. Ecological and Evolutionary Consequences of Herbivory in the Perennial Herb Lythrum salicaria

    Författare :Lina Lehndal; Jon Ågren; Peter Hambäck; Marc Johnson; Uppsala universitet; []
    Nyckelord :Disturbance gradient; Female reproductive success; Galerucella calmariensis; Galerucella pusilla; Herbivore removal; Latitudinal gradient; Local adaptation; Nanophyes marmoratus; Plant-herbivore interactions; Plant size; Resistance to herbivory; Tolerance to damage; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Sammanfattning : In this thesis, I combined field, common-garden and greenhouse experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions in the perennial herb Lythrum salicaria. More specifically I examined (1) whether resistance and tolerance to damage from herbivores vary with latitude and are positively related to the intensity of herbivory in natural populations, (2) whether effects of herbivory on plant fitness vary with latitude, (3) whether populations are locally adapted and whether herbivory influences the relative fitness of populations, and (4) whether the intensity and effects of insect herbivory on reproductive output vary locally along a disturbance gradient and are associated with differences in plant resistance. LÄS MER

  2. 22. Herbivory, phenotypic variation, and reproductive barriers in fucoids

    Författare :Helena Forslund; Lena Kautsky; Ove Eriksson; Stein Fredriksen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Non-indigenous species; Enemy Release Hypothesis; Asexual reproduction; Phlorotannins; Distribution; Plant Ecology; växtekologi;

    Sammanfattning : Along the shores of the Northern hemisphere Fucus (Phaeophyceae) species are a prominent presence, providing substrate, shelter, and food for many species. Fucus evanescens, a non-indigenous species (NIS) in Sweden, and F. LÄS MER

  3. 23. Female Reproductive Strategies in the Ruff (Philomachus pugnax)

    Författare :Katherine Thuman; Fredrik Widemo; Robert Montgommery; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

    Sammanfattning : Traditionally, females have been considered to be strictly monogamous. Today, we know that females in the majority of species actively seek out and mate with several males. Trying to understand female preferences, including what benefits mate choice entails, has been the focus of intense research during the last decades. LÄS MER

  4. 24. Gonad and ejaculate allocation in alternative reproductive tactics of salmon and trout with reference to sperm competition

    Författare :Tomislav Vladić; Michael Taborsky; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; alternative reproductive tactics; sperm competition; brown trout; Atlantic salmon; ATP; ejaculate expenditure; motility; sperm morphology; trade-off; loaded raffle; zoologi; Zoology;

    Sammanfattning : Atlantic salmon, Salmo salar L., and brown trout, Salmo trutta L., exhibit alternative male maturation phenotypes, anadromous and precociously mature parr, which commonly endure in sperm competition at the spawning grounds. LÄS MER

  5. 25. Thermal endometrial destruction by means of a balloon catheter : experimental and clinical evaluation of a new form of treatment for menorrhagia

    Författare :Britt Friberg; Lund Obstetrik och gynekologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; andrologi; Obstetrik; gynekologi; sexuality; gynaecology; andrology; reproduction; Obstetrics; balloon catheter; thermal coagulation; Menorrhagia; endometrial destruction; saline infusion sonography; uterine thermal conductivity; reproduktion; sexualitet;

    Sammanfattning : Thermal endometrial destruction by means of a silicone balloon catheter is a new form of treatment for menorrhagia aimed at reducing menstrual blood loss. The purpose of the present work was to study, experimentally, the thermal effects on and the thermal conductivity of uterine tissue, to obtain a basis for the estimation of optimal treatment conditions by means of numerical analyses using a computer simulation model, to elucidate possible problems which may arise during the procedure, to evaluate how the patients tolerated this treatment and to judge which patients were suitable for this form of treatment and, finally, to study the uterine cavity after treatment and the long-term results of treatment. LÄS MER