Sökning: "Biologi"

Visar resultat 31 - 35 av 6271 avhandlingar innehållade ordet Biologi.

  1. 31. Population divergence at small spatial scales : – theoretical and empirical investigations in perch

    Författare :Sara Bergek; Mats Björklund; Teija Aho; Sarah Goodacre; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Perca fluviatilis L.; Perch; Small scale genetic differentiation; Morphometrics; Isolation by distance; Dispersal; Gene flow; Microsatellites; Spatiotemporal stability; Barriers; Biology; Biologi; Terrestrial; freshwater and marine ecology; Terrestrisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

    Sammanfattning : Genetically structured populations arise when gene flow between groups of individuals is hindered by geographical, behavioural or temporal barriers. The identification of such groups is important for understanding evolution and has large implications for conservation concern. LÄS MER

  3. 32. Grazing and the geographical range of seaweeds : The introduced Fucus evanescens and the newly described Fucus radicans

    Författare :Helena Forslund; Lena Kautsky; Ove Eriksson; Veijo Jormalainen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; non-indigenous species; phlorotannin; herbivore defense; ; Biology; Biologi; Marine ecology; Marin ekologi; Plant Ecology; växtekologi;

    Sammanfattning : Along the coast of temperate oceans brown algae of the genus Fucus form dense stands on rocky shores and are keystone species of the coastal ecosystem. These large seaweeds are perennial and function as substrate for many sessile marine organisms, provide shelter for fauna and juvenile fish, and are food source. A number of abiotic (e.g. LÄS MER

  4. 33. Physiological adaptations in two ecotypes of Fucus vesiculosus and in Fucus radicans with focus on salinity

    Författare :A Maria Gylle; Nils GA Ekelund; Stefan Falk; Pauli Snoeijs; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bothnian Sea; brackish; brown algae; D1; 77 K fluorescence emission; Fucus vesiculosus; Fucus radicans; light-harvest antenna; mannitol; marine; NMR; Norwegian Sea; quantum yield; photosynthetic maximum capacity Pmax ; photosystem; PSI; PSII ; PsaA; Rubisco; salinity.; Biology; Biologi; Plant physiology; Växtfysiologi;

    Sammanfattning : The in origin intertidal marine brown alga Fucus vesiculosus L. grow permanently sublittoral in the brackish Bothnian Sea, side by side with the recently discovered F. radicans L. Bergström et L. LÄS MER

  5. 34. Effects of commercial hatchery processing on behaviour and welfare of laying hens

    Författare :Louise Hedlund; Per Jensen; Charlotta Berg; Bas Rodenburg; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Around the world, more than 76.7 million tons of eggs are consumed every year. To meet this demand, billions of laying hen chicks are produced under highly industrial circum-stances. These chicks are hatched in commercial hatcheries for laying hens in a presumably stressful environment, which might affect their welfare and production later in life. LÄS MER

  7. 35. Artificial neural networks in models of specialization and sympatric speciation

    Författare :Niclas Norrström; Högskolan i Skövde; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Biology; Biologi; Naturvetenskap; Natural sciences;

    Sammanfattning : This thesis deals with specialization and how it is linked to sympatric speciation. The trait driving specialization is a cue recognition trait modelled with artificial neural networks that exploiters use to discriminate beneficial resources from detrimental resources based on the signals of the resources. LÄS MER