Ruminants are dependent on their gut microbiomes for nutrient extraction from plant diets. However, knowledge about the composition, diversity, function, and spatial structure of gut microbiomes, especially in wild ruminants, is limited, largely because analysis has been restricted to faeces or the rumen. In two geographically separated reindeer subspecies, 16S rRNA gene amplicon sequencing revealed ...

Strong seasonality is a key feature of high-latitude systems like the Barents Sea. While the interannual variability and long-term changes of the Barents Sea are well-documented, the seasonal progression of the physical and biological systems is less known, mainly due to poor accessibility of the seasonally ice-covered area in winter and spring. Here, we use an extensive set of physical and biological ...

Seasonal rhythms in humans are fascinating but studying them is inherently challenging due to the need for data that covers multiple years. Due to the experimental obstacles, it remains debated whether humans exhibit seasonal fluctuations in aspects such as activity levels and libido. To approach these topics through indirect digital measures, this thesis used multi-year data from Google Trends ...

In 2019, a new species of sucking louse was observed in arctic foxes (Vulpes lagopus) on Svalbard and Northern Canada. Abnormal patterns of fur loss, inconsistent with normal moult, were observed across the neck, shoulders and back, raising concerns as to how the animals would cope with damaged fur during the cold Arctic winter. This study investigates the impact of these lice on Svalbard arctic ...

Polyploidization can be a rapid path to speciation and is considered an important evolutionary mechanism. Some predict that all plants have undergone a polyploidization event during their evolutionary history, and the frequency of polyploid species increases with latitude. The Arctic-Alpine Saxifraga oppositifolia, an autopolyploid, has two polyploids that have successfully established themselves ...

The brain is highly dependent on oxygen for its metabolism and, in most mammals, major brain dysfunction occurs already within minutes of insufficient oxygen supply (hypoxia). Oxygen is the final electron acceptor in the electron transport system that drives the production of ATP through oxidative phosphorylation in the mitochondria. The rate at which oxidative phosphorylation produces ATP is dependent ...

Understanding drivers of mercury (Hg) accumulation in freshwater food webs is vital due to its ability to accumulate in organisms and magnify in food webs to potent levels, potentially impacting wildlife and human health. This is of particular concern in regions where fish serve as an important food source. This study explores drivers of Hg accumulation in European perch (Perca fluviatilis) across ...

Blue mussels (Mytilus spp.) are important ecosystem bioengineers and provide numerous of ecosystem services. They are found worldwide, but face a global population decline for unclear reasons in many regions. A pilot study in the subarctic rocky intertidal shore in Northern Norway revealed an unexpected unimodal pattern in the body size of blue mussels along a vertical transect from low to high ...

Methane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated ...

Classification of zooplankton to species with broadband echosounder data could increase the taxonomic resolution of acoustic surveys and reduce the dependence on net and trawl samples for ‘ground truthing’. Supervised classification with broadband echosounder data is limited by the acquisition of validated data required to train machine learning algorithms (‘classifiers’). We tested the hypothesis ...