A5009852282- Avian ecology and behavior
- Animal Behavior and Reproduction
- Genetic diversity and population structure
- Wildlife Ecology and Conservation
- Plant and animal studies
- Genetic and phenotypic traits in livestock
- Fish Ecology and Management Studies
- Identification and Quantification in Food
- Ecology and biodiversity studies
- Forest Management and Policy
- Insect and Arachnid Ecology and Behavior
- Environmental DNA in Biodiversity Studies
- European and International Law Studies
- Arctic and Russian Policy Studies
- Indigenous Studies and Ecology
- Species Distribution and Climate Change
- International Maritime Law Issues
- Animal Ecology and Behavior Studies
- Botany and Plant Ecology Studies
- Forest Ecology and Biodiversity Studies
- Genetic Mapping and Diversity in Plants and Animals
- Bird parasitology and diseases
- Reproductive biology and impacts on aquatic species
- Evolutionary Psychology and Human Behavior
- Wildlife-Road Interactions and Conservation
Norwegian Institute for Nature Research
2016-2025
Tel Aviv University
2024
University of Oslo
2007-2022
UiT The Arctic University of Norway
2020
Bielefeld University
2020
Nord University
2019
NILU
2012
Bodoland University
2010
American Museum of Natural History
2005-2008
Norwegian University of Science and Technology
1999
1. Why are some common and apparently suitable resources avoided by potential users? This interesting ecological evolutionary conundrum is vividly illustrated obligate brood parasites. Parasitic birds lay their eggs into nests of a wide range host species, including many rare ones, but do not parasitize commonly co-occurring hosts. 2. Attempts to explain the absence parasitism in hosts limited typically focused on single-factor explanations while ignoring other factors. We tested why...
Spermatozoa are among the most diversified cells in animal kingdom, but underlying evolutionary forces affecting intraspecific variation sperm morphology poorly understood. It has been hypothesized that competition is a potent selection pressure on within species. Here, we examine total length of 22 wild passerine bird species (21 genera, 11 families) relation to risk competition, as expressed by frequency extrapair paternity and relative testis size. We demonstrate, using phylogenetic...
Sperm swimming speed is an important determinant of male fertility and sperm competitiveness. Despite its fundamental biological importance, the underlying evolutionary processes affecting this reproductive trait are poorly understood. Using a comparative approach in phylogenetic framework, we tested predictions that swim faster with (1) increased risk competition, (2) shorter duration female storage, (3) length. We recorded 42 North American European free-living passerine bird species,...
Female promiscuity is highly variable among birds, and particularly songbirds. Comparative work has identified several patterns of covariation with social, sexual, ecological life history traits. However, it unclear whether these reflect causes or consequences female promiscuity, if they are byproducts some unknown evolutionary drivers. Moreover, factors that explain at the deep nodes in phylogenetic tree may be different from those important tips, i.e. closely related species. Here we...
Reintroductions may produce populations that suffer from decreasing genetic diversity due to isolation, drift and inbreeding if not assisted by careful management. To assess the outcomes of reintroductions in large carnivores, we used Eurasian lynx (Lynx lynx) as a case study, which was subject several reintroduction attempts over last 50 years. Although some restocking actions initially appeared successful, recovery has stagnated recent reveal potential causes slow Europe, examined...
Background The rate of extrapair paternity is a commonly used index for the risk sperm competition in birds, but data exist only few percent approximately 10400 extant species. As analyses require extensive field sampling and costly lab work, species coverage this will probably not improve much foreseeable future. Recent findings from passerine which constitute largest avian order (∼5 900 species), suggest that phenotypes carry signature competition. Here we examine how well standardized...
Microsatellites are frequently used genetic markers in a wide range of applications, primarily due to their high length polymorphism levels that can easily be genotyped by fragment analysis. However, the mode microsatellite evolution is yet not fully understood, and role interrupting motifs for stability microsatellites remains explored more detail. Here we present sequence analysis mutation events description structure repeated regions hypervariable, pentanucleotide locus HrU10 barn...
Abstract Mitochondrial DNA usually shows low sequence variation within and high divergence among species, which makes it a useful marker for phylogenetic inference barcoding. A previous study on the common redstart ( P hoenicurus phoenicurus ) revealed two very different mt haplogroups (5% K2P distance). This is comparable to that many sister species; however, both coexist interbreed in Europe today. Herein, we describe phylogeographic pattern of these lineages test hypotheses how such...
One of the great evolutionary puzzles is why hosts parasitic birds discriminate finely against alien eggs, but almost never chicks. A theoretical model has shown that an adaptive host response to eggs can be based on learning. However, learned nestling discrimination too costly favoured by selection in evicting parasites, such as European cuckoo (Cuculus canorus). Indeed, chick rejection been reported for any species. As maladaptive, one expect a viable alternative would use mechanisms not...
Why do females of many species mate with more than one male? One the main hypotheses suggests that female promiscuity is an insurance mechanism against potential detrimental effects inbreeding. Accordingly, should preferably less related males in multiple or extrapair mating. Here we analyse paternity, relatedness among mating partners, and between parents offspring, socially monogamous North American barn swallow ( Hirundo rustica erythrogaster ). In contrast to inbreeding avoidance...
Understanding spatio-temporal variation in the diet of alpine herbivores is important to predict how a changing climate will affect these species future. We examined willow ptarmigan ( Lagopus l. lagopus ) using DNA metabarcoding fecal pellets sampled from winter early summer over three consecutive years. Furthermore, we assessed snow cover and vegetation phenology affected variation. also investigated sex differences composition. identified 18 taxa genera Betula, Vaccinium Empetrum occurred...
In birds with extrapair mating, older males usually have higher fertilization success than younger males. Two hypotheses can potentially explain this pattern: 1) females prefer older, and often more ornamented males, or 2) invest in reproduction fertility Here we studied factors associated age-related male a population of barn swallows Hirundo rustica Canada. We document that increased gradually up to minimum age four-year old. The effect was especially strong for the number offspring...
Epigenetic mechanisms such as methylation can influence gene expression and play a crucial role in the adaptation to local environmental conditions, thereby introducing non-genetic variability within species. Here, using Reduced Representation Bisulfite Sequencing approach (RRBS), we compared patterns blood muscle across three European brown bear populations. Our results clearly demonstrated that, beyond tissue-driven divergences, of populations are significantly distinct. Differentially...
Mammalian dispersal is characterized by long‐distance movements, and whether sex‐dependent occurs at pre‐saturation densities affects colonization speed concurrent pathogen spread. In Scandinavia, Sweden classifies wild boar Sus scrofa as a native species retains high densities, while Norwegian authorities considers it an alien invasive maintains the population minimum. With long shared border recent detection of African swine fever (ASF) in Sweden, into Norway concern. Using high‐density...
We investigated the level of parasitism, egg mimicry and breeding success cuckoos parasitising four sympatric species Acrocephalus warblers in southern Moravia, Czech Republic. The parasitism rate was highest marsh warbler palustris (44.8%) followed by great reed A. arundinaceus (33.8%), sedge schoenobaenus (26.5%) scirpaceus (11.6%). Although cuckoo eggs showed a high this host rejected 72% eggs, resulting only 4.3%. Cuckoo laid nests similar hatching success, but chicks survived better...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 375:219-228 (2009) - DOI: https://doi.org/10.3354/meps07774 Sperm characteristics and competitive ability in farmed wild cod Jon E. Skjæraasen1,*, Ian Mayer1,5, Justin J. Meager1, Geir Rudolfsen2, Ørjan Karlsen3, Thomas Haugland2, Oddmund Kleven4 1Department of Biology, University Bergen, 5020 Norway...