Studies of reproductive isolation between homoploid hybrid species and their parent species have rarely been carried out. Here we investigate reproductive barriers between a recently recognized hybrid bird species, the ...

Spatio-temporal density-dependent processes are crucial regulatory factors for natural populations. However, there is a lack of studies addressing spatial density-dependence in fish growth. A previous investigation has ...

Background: Today, there are more than a hundred times as many sequenced prokaryotic genomes than were present in the year 2000. The economical sequencing of genomic DNA has facilitated a whole new approach to microbial ...

One mechanism by which marine organisms may respond to climate shifts is range shifts. The corkwing wrasse (Symphodus melops) is a temperate fish species, inhabiting the coasts of Europe, that show strong indications of ...

The forage-maturation hypothesis (FMH) states that herbivores migrate along a phenological gradient of plant development in order to maximize energy intake. Despite strong support for the FMH, the actual relationship between ...

Background Pockmarks (depressions in the seabed) have been discovered throughout the world’s oceans and are often related to hydrocarbon seepage. Although high concentrations of pockmarks are present in ...

Background The deer ked (Lipoptena cervi), a hematophagous ectoparasite of Cervids, is currently spreading in Scandinavia. In Norway, keds are now invading the south-eastern part of the country and the ...

Background Calpains are Ca2+-dependent cysteine proteases that participate in a range of crucial cellular processes. Dysfunction of these enzymes may cause, for instance, life-threatening diseases in humans, ...

Phytoplankton is main producers of marine pelagic food webs, acting as link between the energy source, the sun, and consumers. Phytoplankton is an evolutionary diverse group whick is, however, traditionally assembled due ...

Interactions between plant roots and fungi are well known from most terrestrial ecosystems. Mycorrhizal association is the most prominent plant-fungi interaction, where the fungal partners increase the water and nutrient ...

The present study is the first attempt to explore the rate, characteristics and legal reactions to neonaticide in Norway during the years 1990 – 2009. Potential incidents of neonaticide were identified through the national ...

In: Pagou, P. and Hallegraeff, G. (eds). Proceedings of the 14th International Conference on Harmful Algae. International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO 2012 ...

In: Pagou, P. and Hallegraeff, G. (eds). Proceedings of the 14th International Conference on Harmful Algae. International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO ...

Background: Tick-borne encephalitis (TBE) is among the most important vector borne diseases of humans in Europe and is currently identified as a major health problem in many countries. TBE endemic zones have expanded over ...

Nuisance growth of the aquatic macrophyte Juncus bulbosus has been observed since the 1980s in an increasing number of rivers and lakes in northern Europe. What causes such massive growth is not well understood, however, ...

Harvesting wild populations may contrast or reinforce natural agents of selection and potentially cause evolutionary changes in life-history traits such as growth and maturation. Harvest selection may also act on behavioral ...

Understanding why some hybrid zones are bimodal and others unimodal can aid in identifying barriers to gene exchange following secondary contact. The hybrid zone between the grasshoppers Chorthippus brunneus and C. jacobsi ...

The dinoflagellates are a diverse lineage of microbial eukaryotes. Dinoflagellate monophyly and their position within the group Alveolata are well established. However, phylogenetic relationships between dinoflagellate ...

Background Interstitial Cystitis (IC) is a chronic inflammatory condition of the bladder with unknown etiology. The aim of this study was to characterize the microbial community present in the urine from ...

Atlantic salmon populations are reported to be declining throughout its range, raising major management concerns. Variation in adult fish abundance may be due to variation in survival, growth, and timing of life history ...

When plastids are transferred between eukaryote lineages through series of endosymbiosis, their environment changes dramatically. Comparison of dinoflagellate plastids that originated from different algal groups has revealed ...

There is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. Evidence for pre-copulatory sexual selection effects on sperm traits, on the ...

Background: Climate change threatens maize productivity in sub-Saharan Africa. To ensure food security, access to locally adapted genetic resources and varieties is an important adaptation measure. Most of the maize grown ...

Pleistocene climate changes have imposed extreme conditions to intertidal rocky marine communities, forcing many species to significant range shifts in their geographical distributions. Phylogeographic analyses based on ...

Background: Outbreaks of pancreas disease (PD) greatly contribute to economic losses due to high mortality, control measures, interrupted production cycles, reduced feed conversion and flesh quality in the aquaculture ...

Recent multilocus studies of congeneric birds have shown a pattern of elevated interspecific divergence on the Z chromosome compared to the autosomes. In contrast, intraspecifically, birds exhibit less polymorphism on the ...

The seasonal timing of avian reproduction is supposed primarily to coincide with favourable feeding conditions. Long-term changes in avian breeding phenology are thus mostly scrutinized in relation to climatic factors and ...

Atlantic cod (Gadus morhua) is a large, cold-adapted teleost that sustains long-standing commercial fisheries and incipient aquaculture. Here we present the genome sequence of Atlantic cod, showing evidence for complex ...

Background The fungal genus Serpula (Serpulaceae, Boletales) comprises several saprotrophic (brown rot) taxa, including the aggressive house-infecting dry rot fungus Serpula lacrymans. Recent phylogenetic ...

Background:The implementation of high throughput sequencing for exploring biodiversity poses high demands on bioinformatics applications for automated data processing. Here we introduce CLOTU, an online and open access ...

Background Methane oxidizing prokaryotes in marine sediments are believed to function as a methane filter reducing the oceanic contribution to the global methane emission. In the anoxic parts of the sediments, ...

Background Bovine babesiosis is regarded as a limited health problem for Norwegian cows, and the incidence has decreased markedly since the 1930s. Rare cases of babesiosis in splenectomised humans from ...

Background The two homologous iron-binding lobes of transferrins are thought to have evolved by gene duplication of an ancestral monolobal form, but any conserved synteny between bilobal and monolobal ...

Background Following colonization of new habitats and subsequent selection, adaptation to environmental conditions might be expected to be rapid. In a mountain lake in Norway, Lesjaskogsvatnet, more than ...

Background Effects of polyploidisation on gene flow between natural populations are little known. Central European diploid and tetraploid populations of Arabidopsis arenosa and A. lyrata are here used to ...

Background Urine within the urinary tract is commonly regarded as "sterile" in cultivation terms. Here, we present a comprehensive in-depth study of bacterial 16S rDNA sequences associated with urine from ...

Background One important physiological response to environmental stress in animals is change in gene expression. To obtain reliable data from gene expression studies using RT-qPCR it is important to evaluate ...

Background Cell lines from Atlantic salmon kidney have made it possible to culture and study infectious salmon anemia virus (ISAV), an aquatic orthomyxovirus affecting farmed Atlantic salmon. However, ...

The thesis introduces a new integrated approach to ecological and evolutionary modeling, the goal of which is to create an analytical platform for applied interdisciplinary researches. This Conspecific Community Dynamics ...

Birdsong is a species-specific signal that is used in mate attraction and intrasexual competition. This thesis concerns song acquisition in two oscine songbird species, the great tit Parus major and the pied flycatcher ...

Polyploidy, i.e., the duplication of entire nuclear genomes, has shaped the evolution of major lineages of eukaryotes, and is particularly important in the Plant Kingdom. Molecular analyses suggest that the genomes of most ...

Delayed density-dependent demographic processes are thought to be the basis for multi-annual cyclic fluctuations in small rodent populations, but evidence for delayed density dependence of a particular demographic trait ...

Rødkinnet spyflue (Calliphora vicina) er et alvorlig skadedyr i norsk tørrfiskproduksjon. I dårlige år forårsaker insektene et økonomisk tap som overskrider 10 millioner kroner. Problemene oppstår når fluene legger egg på ...

The interactions between seabirds and their environment, notably their prey, include complex spatial patterns and mechanisms that span over different scales of processes (e.g. physiology, behaviour, population). To understand ...

Crustose lichen communities on rocks exhibit fascinating spatial mosaics resembling political maps of nations or municipalities. Although the establishment and development of biological populations are important themes in ...

Background We have previously sequenced more than 500 kb of the duplicated MHC class I regions in Atlantic salmon. In the IA region we identified the loci for the MHC class I gene Sasa-UBA in addition to a ...

Background Human cases of plague (Yersinia pestis) infection originate, ultimately, in the bacterium's wildlife host populations. The epidemiological dynamics of the wildlife reservoir therefore determine ...

Background Cardiomyopathy syndrome (CMS) is a severe disease affecting large farmed Atlantic salmon. Mortality often appears without prior clinical signs, typically shortly prior to slaughter. We recently ...

Background The genomes of higher plants are, on the majority, polyploid, and hybridisation is more frequent in plants than in animals. Both polyploidisation and hybridisation contribute to increased ...

Background The incidence of bovine babesiosis, caused by Babesia divergens (Apicomplexa: Piroplasmida) has decreased markedly since the 1930 s, but may re-emerge as a consequence of climate change and ...

Background Plastid replacements through secondary endosymbioses include massive transfer of genes from the endosymbiont to the host nucleus and require a new targeting system to enable transport of the ...

Background DNA-dependent RNA polymerase IV and V (Pol IV and V) are multi-subunit enzymes occurring in plants. The origin of Pol V, specific to angiosperms, from Pol IV, which is present in all land plants, ...

Background Evaluating the limits of adaptation to temperature is important given the IPCC-predicted rise in global temperatures. The rate and scope of evolutionary adaptation can be limited by low genetic ...

Background Dryas octopetala is a widespread dwarf shrub in alpine and arctic regions that forms ectomycorrhizal (ECM) symbiotic relationships with fungi. In this study we investigated ...

Background Recent surveys of eukaryote 18S rDNA diversity in marine habitats have uncovered worldwide distribution of the heterotrophic eukaryote phylum Telonemia. Here we investigate the diversity and ...

Background The vertebrate globin genes encoding the α- and β-subunits of the tetrameric hemoglobins are clustered at two unlinked loci. The highly conserved linear order of the genes flanking the hemoglobins ...

Background During the last 15 years the internal transcribed spacer (ITS) of nuclear DNA has been used as a target for analyzing fungal diversity in environmental samples, and has recently been selected as ...

Background The mating type loci that govern the mating process in fungi are thought to be influenced by negative frequency-dependent selection due to rare allele advantage. In this study we used a mating ...

This thesis focuses on the natural history of the dry rot fungus Serpula lacrymans and closely related taxa within Serpulaceae. In the first study the phylogenetic relationships within Serpulaceae have been investigated ...

In this thesis I have studied connectivity processes affecting the population structure of coastal cod on the Norwegian Skagerrak coast. I have focused on three aspects of the processes. Firstly the dynamics and the integrity ...

Klimaforandringer gir drastiske endringer i mengden av organisk karbon i innsjøer og vi imøtegår en fremtid med brunere vann. Det er en av konklusjonene til Søren Larsens doktorgradsavhandling som er utført ved Biologisk ...

Background: Large multigene sequence alignments have over recent years been increasingly employed for phylogenomic reconstruction of the eukaryote tree of life. Such supermatrices of sequence data are preferred over single ...

Denne avhandlingen viser at fisk utsatt for lave nivåer av produsertvann over lang tid kan utvikle skader på arvematerialet, modnes senere og få redusert vekst. Produsertvann er et biprodukt fra utvinningen av olje og ...

Pockmarks have now been recognised for nearly four decades, and are one of the most obvious and abundant structural features of the seafloor in some areas, yet there is still little knowledge of their influence on fauna ...

Background Genetic variation has been shown to play a significant role in determining susceptibility to the salmon louse, Lepeophtheirus salmonis. However, the mechanisms involved in differential response ...

Background In order to understand the role of herbivores in trophic webs, it is essential to know what they feed on. Diet analysis is, however, a challenge in many small herbivores with a secretive life ...

The main objective of these studies was to utilize the large amount of co-occurring fauna and chemical data collected in different contamination zones around offshore installations to derive ecologically relevant protection ...

Climate change and overfishing are increasingly causing unanticipated changes in marine ecosystems (e.g. shifts in species dominance). In order to understand and anticipate these changes, there is a crucial need for ...

Background Cyanobacteria often produce several different oligopeptides, with unknown biological functions, by nonribosomal peptide synthetases (NRPS). Although some cyanobacterial NRPS gene cluster types ...

Background To conduct phylogeographic or population genetic studies, an adequate number of DNA markers for the focal species are required. Due to severe unavailability of genotype markers of any kind for ...

Background Although some mechanisms of habitat adaptation of conspecific populations have been recently elucidated, the evolution of female preference has rarely been addressed as a force driving habitat ...

Alzheimers sykdom, Parkinsons sykdom og hjerneslag er assosiert med nevrodegenerering i visse deler av hjernen. Overstimulering av glutamatreseptorer med medfølgende produksjon av frie radikaler har blitt foreslått å være ...

High nitrate (NO3) leaching rates have been observed in mountain and heathland areas in Europe at sites receiving high levels of nitrogen (N) deposition. These areas are characterised by sparse vegetation on thin, patchy ...

Background Identification of DNA sequence diversity is a powerful means for assessing the species present in environmental samples. The most common molecular strategies for estimating taxonomic composition ...

Background Cyanobacteria produce a wealth of secondary metabolites, including the group of small cyclic heptapeptide hepatotoxins that constitutes the microcystin family. The enzyme complex that directs the ...

Background Despite several thousands of years of close contacts, there are genetic differences between the neighbouring countries of Finland and Sweden. Within Finland, signs of an east-west duality have ...

Background Cyanopeptolins are nonribosomally produced heptapetides showing a highly variable composition. The cyanopeptolin synthetase operon has previously been investigated in three strains from the genera ...

Marine trepigget stingsild (Gasterosteus aculeatus) har kolonisert ulike ferskvannshabitat gjentatte ganger og denne koloniseringen har ført til ulikheter innen trekk som morfologi, atferd, fysiologi og livshistorie. Disse ...

Imagine if salmon snared on a hook or fish caught in a net were to scream and shout when they were extracted from the water. What would sports fishing and professional fishing have been like then? Would fish farming have ...

This thesis investigates competition and ecological speciation by comparing habitat use, foraging ecology and physiology of two fish populations (Coregonus spp.) in a temperate lake. It demonstrates that dietary differences ...

Cyanobakterier (=blågrønnalger) forekommer i nesten alle norske innsjøer, og masseoppblomstringer av dem har vist seg å være utbredt over hele verden. Et stort problem ved oppblomstringer av cyanobakterier er giftstoffene ...

I dette arbeidet har vi utviklet molekylære metoder for simultant å måle forekomsten av ulike mikrober i komplekse samfunn. Koblet med økologisk analyse gir dette oss helt nye muligheter til å forstå hvordan bakteriesamfunn ...

In most cases, the proliferation of marine planktonic alga is ecologically beneficial for the marine food web. However, harmful algal blooms can have negative effects by causing fish kills. In this PhD thesis particularly ...

In this thesis I report on several aspects of the reproductive ecology of the short-lived, monocarpic plant Digitalis purpurea L. (Plantaginaceae). Observational field studies are combined with controlled crosses and ...

Abstract In order to investigate the effect of different polluting agents to fungi, there is an obvious need for methods for estimating fungal growth. Given that the traditional methods are not accurate and efficient enough, ...

Foraging ecology and environmental conditions have represented important driving forces in the evolution of both dental morphology as well as the digestive system. Teeth are essential for digestive processes in ruminants, ...

The aim of this thesis is to investigate the ecology and ethnobotany of vegetation in Benishangul Gumuz Regional State (BGRS), western Ethiopia. The studies reported in this thesis have confirmed the existence of 1102 ...

I artikkelsamlingen kan du lese om pedagogiske endringer i krysningspunktet mellom teknologi, organisering og læring. Du finner artikler fra en rekke ulike fagmiljøer som beskriver prosjekter av mange ulike slag. Erfaringene ...

Climate influences a population through a variety of processes, including reproduction, growth, migration patterns and phenology. Climate may operate either directly through metabolic and reproductive processes or indirectly ...

Background The genetic architecture of a quantitative trait influences the phenotypic response to natural or artificial selection. One of the main objectives of genetic mapping studies is to identify the ...

Background The endemic Hawaiian mints represent a major island radiation that likely originated from hybridization between two North American polyploid lineages. In contrast with the extensive morphological ...

The polymeric Ig receptor (pIgR), also called membrane secretory component (SC), mediates epithelial transcytosis of polymeric immunoglobulins (pIgs). J Chain-containing polymeric IgA (pIgA) and pentameric IgM bind pIgR ...

ABSTRACT Cell-based assays are useful and effective for biomonitoring and toxicity screening purposes, and there is a need for fast, routine and simple screening assays. An assay to detect the production of reactive oxygen ...

SAMMENDRAG Celler er kontinuerlig utsatt for påvirkninger som kan skade dets DNA. Dette inkluderer oksidative DNA-skader, som oppstår via normal oksidativ metabolisme, og fra forbindelser i miljøet. Slike DNA-skader kan ...