Blar i NTNU Open på forfatter "Jensen, Henrik"
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A battle of the mountains: Intraguild competition between arctic fox Vulpes lagopus and red fox Vulpes vulpes
Grevskott, Ragnhild Thorseth (Master thesis, 2019)Fjellreven (Vulpes lagopus) er en truet art i Fennoskandia. Konkurranse med rødreven (Vulpes vulpes) er regnet som en av hovedtruslene for fjellrevens utbredelse. Flere bevaringstiltak har blitt satt i gang for å redde ... -
A Continuous-Time, Discrete-Space Statistical Model for Estimating Dispersal Rate Applied to a Population of House Sparrows (Passer Domnesticus) in Northern Norway
Drahus, Kristin Mathilde (Master thesis, 2015)How individuals move and interact with each other is a complex matter. Even so, the knowledge of how such movements and interactions happen is important to understand in order to be able to keep genetic variation and ... -
Acclimation Potential to a Future Ocean Acidification Scenario in the Key Copepod Species Calanus finmarchicus: - with emphasis on the genetic contribution to the acclimation response
Aase, Marit (Master thesis, 2014)Ocean acidification, as a result of the increased concentration of carbon dioxide in the ocean, poses a threat towards marine ecosystems through lowered pH and altered seawater chemistry. The marine copepod Calanus ... -
Animal Models and Integrated Nested Laplace Approximations
Holand, Anna Marie; Steinsland, Ingelin; Martino, Sara; Jensen, Henrik (Journal article; Peer reviewed, 2013)Animal models are generalized linear mixed models used in evolutionary biology and animal breeding to identify the genetic part of traits. Integrated Nested Laplace Approximation (INLA) is a methodology for making fast, ... -
Animal models with group-specific additive genetic variances: extending genetic group models
Muff, Stefanie; Niskanen, Alina Katariina; Saatoglu, Dilan; Keller, Lukas; Jensen, Henrik (Journal article; Peer reviewed, 2019)Background The animal model is a key tool in quantitative genetics and has been used extensively to estimate fundamental parameters, such as additive genetic variance or heritability. An implicit assumption of animal ... -
Are immigrants outbred and unrelated? Testing fundamental assumptions in a wild metapopulation
Dickel, Lisa; Arcese, Peter; Nietlisbach, Pirmin; Keller, Lukas F.; Jensen, Henrik; Reid, Jane Margaret (Journal article; Peer reviewed, 2021) -
Artificial size selection experiment reveals telomere length dynamics and fitness consequences in a wild passerine
Pepke, Michael Le; Kvalnes, Thomas; Rønning, Bernt; Jensen, Henrik; Boner, Winnie; Sæther, Bernt-Erik; Monaghan, Pat; Ringsby, Thor Harald (Peer reviewed; Journal article, 2022)Telomere dynamics could underlie life-history trade-offs among growth, size and longevity, but our ability to quantify such processes in natural, unmanipulated populations is limited. We investigated how 4 years of artificial ... -
Causes and consequences of individual variation in fitness-related traits in house sparrows.
Jensen, Henrik (Doctoral thesis, 2002)Human activity has caused an increase in the fragmentation of natural habitats, especially during the last couple of centuries. This means that populations of wild species are split into smaller sub-populations often ... -
Causes and consequences of variation in early-life telomere length in a bird metapopulation
Pepke, Michael Le; Kvalnes, Thomas; Ranke, Peter Sjolte; Araya-Ajoy, Yimen; Wright, Jonathan; Sæther, Bernt-Erik; Jensen, Henrik; Ringsby, Thor Harald (Peer reviewed; Journal article, 2022)Environmental conditions during early-life development can have lasting effects shaping individual heterogeneity in fitness and fitness-related traits. The length of telomeres, the DNA sequences protecting chromosome ends, ... -
Changes in inbreeding level across different life stages in an insular house sparrow metapopulation in northern Norway.
Shrestha, Nitya (Master thesis, 2024)Inbreeding and inbreeding depression have been a major challenge for conserving small and isolated populations. The viability of endangered species has been threatened by inbreeding depression; thus, it has been an ... -
Characterizing morphological (co)variation using structural equation models: Body size, allometric relationships and evolvability in a house sparrow metapopulation
Araya-Ajoy, Yimen; Ranke, Peter Sjolte; Kvalnes, Thomas; Rønning, Bernt; Holand, Håkon; Myhre, Ane Marlene; Pärn, Henrik; Jensen, Henrik; Ringsby, Thor Harald; Sæther, Bernt-Erik; Wright, Jonathan (Peer reviewed; Journal article, 2019)Body size plays a key role in the ecology and evolution of all organisms. Therefore, quantifying the sources of morphological (co)variation, dependent and independent of body size, is of key importance when trying to ... -
Contrasting genomic consequences of anthropogenic reintroduction and natural recolonization in high-arctic wild reindeer
Burnett, Hamish Andrew; Bieker, Vanessa Carina; Le Moullec, Mathilde; Peeters, Bart; Rosvold, Jørgen; Pedersen, Åshild Ønvik; Dalén, Love; Loe, Leif Egil; Jensen, Henrik; Hansen, Brage Bremset; Martin, Michael David (Peer reviewed; Journal article, 2023)Anthropogenic reintroduction can supplement natural recolonization in reestablishing a species' distribution and abundance. However, both reintroductions and recolonizations can give rise to founder effects that reduce ... -
Controlling for P-value inflation in allele frequency change in experimental evolution and artificial selection experiments
Kemppainen, Petri; Rønning, Bernt; Kvalnes, Thomas; Hagen, Ingerid Julie; Ringsby, Thor Harald; Billing, Anna Maria; Pärn, Henrik; Lien, Sigbjørn; Husby, Arild; Sæther, Bernt-Erik; Jensen, Henrik (Journal article; Peer reviewed, 2017)Experimental evolution studies can be used to explore genomic response to artificial and natural selection. In such studies, loci that display larger allele frequency change than expected by genetic drift alone are assumed ... -
Covarying Behaviours and Innovation in a House Sparrow Metapopulation - Implications for Social Foraging
Hammerås, John (Master thesis, 2016)Individuals in populations of many species have been found to differ consistently in suites of correlating behavioural measures. These phenomena appear to be heritable and subject to selection, thus making it as important ... -
Demographic and genetic consequences of dispersal in house sparrows
Ranke, Peter Sjolte (Doctoral theses at NTNU;2019:24, Doctoral thesis, 2019)The importance of dispersal in population dynamics is widely acknowledged. Key to understand population consequences of dispersal is by quantifying the demographic and genetic contribution from dispersers. The influence ... -
Demographic influences of translocated individuals on a resident population of house sparrows
Ranke, Peter Sjolte; Skjelseth, Sigrun; Pärn, Henrik; Herfindal, Ivar; Borg Pedersen, Åsa Alexandra; Stokke, Bård Gunnar; Kvalnes, Thomas; Ringsby, Thor Harald; Sæther, Bernt-Erik; Jensen, Henrik (Journal article; Peer reviewed, 2017)Translocation of individuals from source populations to augment small populations facing risk of extinction is an important conservation tool. Here we examine sex-specific differences between resident and translocated house ... -
Disentangling the age-dependent causal pathways affecting multiple paternity in house sparrows
Søraker, Jørgen Skavdal (Master thesis, 2022)De drivende mekanismene bak fordelingen av polygami hos sosialt monogame fuglearter har fått mye oppmerksomhet de siste tiårene. Alder og morfologi, og særlig sekundære seksuelle trekk, har ofte blitt pekt på som viktige ... -
Dispersal in a house sparrow metapopulation: An integrative case study of genetic assignment calibrated with ecological data and pedigree information
Saatoglu, Fikriye Dilan; Niskanen, Alina Katariina; Kuismin, Markku; Ranke, Peter Sjolte; Hagen, Ingerid Julie; Araya-Ajoy, Yimen; Kvalnes, Thomas; Pärn, Henrik; Rønning, Bernt; Ringsby, Thor Harald; Sæther, Bernt-Erik; Husby, Arild; Sillanpää, Mikko J.; Jensen, Henrik (Peer reviewed; Journal article, 2021)Dispersal has a crucial role determining ecoevolutionary dynamics through both gene flow and population size regulation. However, to study dispersal and its consequences, one must distinguish immigrants from residents. ... -
Diversity, Loss, and Gain of Malaria Parasites in a Globally Invasive Bird
Marzal, Alfonso; Ricklefs, Robert E.; Valkiunas, Gediminas; Albayrak, Tamer; Arriero, Elena; Bonneaud, Camille; Czirjak, Gabor A.; Ewen, John; Hellgren, Olof; Horakova, Dita; Iezhova, Tatjana A.; Jensen, Henrik; Krizanauskiene, Asta; Lima, Marcos R.; de Lope, Florentino; Magnussen, Eydfinn; Martin, Lynn B.; Møller, Anders P.; Palinauskas, Vaidas; Pap, Peter L.; Perez-Tris, Javier; Sehgal, Ravinder N. M.; Soler, Manuel; Szöllösi, Eszter; Westerdahl, Helena; Zetindjiev, Pavel; Bensch, Staffan (Journal article; Peer reviewed, 2011)Invasive species can displace natives, and thus identifying the traits that make aliens successful is crucial for predicting and preventing biodiversity loss. Pathogens may play an important role in the invasive process, ... -
Does individual variation in producer-scrounger behavior covary with individual life-histories?
Drangsland, Markus (Master thesis, 2023)SAMMENDRAG Denne oppgaven utforsker forholdet mellom dyrs atferd, personlighet, fysiologi og livstempo-syndromer (POLS). Dyrepersonlighet refererer til konsistente individuelle atferdsvariasjoner. Jeg hadde som mål å ...