Blar i NTNU Open på forfatter "Wright, Jonathan"
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A General Stochastic Dynamic Model of the Differential Allocation Hypothesis
Haaland, Thomas Ray (Master thesis, 2015)Differential allocation (DA), adjusting reproductive investment according to the quality of the current mate, is an area of evolutionary behavioral ecology subject to much confusion, with vague terminology, apparently ... -
An experimental test of optimal sampling behaviour in Siberian jays (Perisoreus infaustus)
Sødal, Liv Randi Henøen (Master thesis, 2010)Optimal foraging models tend to assume that animals have perfect information. However, the world is constantly changing, and so it is likely that animals benefit from gathering better knowledge much of the time. Therefore, ... -
Behavioural traits correlate in zebrafish (Danio rerio) selected for high and low upper thermal tolerance
Brusevold, Tine Elisabeth Dahl (Master thesis, 2019)Ferskvannssystemer er spesielt sårbare for klimaforandringer, så forskning på ferskvannsorganismer i lys av temperaturforandringer er viktig. I denne studien, ble sebrafisk selektert gjennom fire generasjoner for øvre ... -
Bet-hedging across generations can affect the evolution of variance-sensitive strategies within generations
Haaland, Thomas; Wright, Jonathan; Ratikainen, Irja Ida (Journal article; Peer reviewed, 2019)In order to understand how organisms cope with ongoing changes in environmental variability, it is necessary to consider multiple adaptations to environmental uncertainty on different time scales. Conservative bet-hedging ... -
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, ... -
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 patterns of density-dependent selection at different life stages can create more than one fast–slow axis of life-history variation
Wright, Jonathan; Solbu, Erik Blystad; Engen, Steinar (Journal article; Peer reviewed, 2020)There has been much recent research interest in the existence of a major axis of life‐history variation along a fast–slow continuum within almost all major taxonomic groups. Eco‐evolutionary models of density‐dependent ... -
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 ... -
dalmatian: A Package for Fitting Double Hierarchical Linear Models in R via JAGS and nimble
Bonner, Simon; Mutzel, Ariane; Kim, Han-Na; Westneat, David F.; Wright, Jonathan; Schofield, Matthew (Peer reviewed; Journal article, 2021)Traditional regression models, including generalized linear mixed models, focus on understanding the deterministic factors that affect the mean of a response variable. Many biological studies seek to understand non-deterministic ... -
Demographic measures of an individual's "pace of life": fecundity rate, lifespan, generation time, or a composite variable?
Araya-Ajoy, Yimen; Bolstad, Geir Hysing; Brommer, Jon; Careau, Vincent; Dingemanse, Niels J.; Wright, Jonathan (Journal article; Peer reviewed, 2018)Comparative analyses have demonstrated the existence of a ^pace-of-life^ (POL) continuum of life-history strategies, from fastreproducing short-lived species to slow-reproducing long-lived species. This idea has been ... -
Describing posterior distributions of variance components: Problems and the use of null distributions to aid interpretation
Pick, Joel; Kasper, Claudia; Allegue, Hassen; Dingemanse, Niels J.; Dochtermann, Ned A.; Laskowski, Kate L.; Lima, Marcos R.; Schielzeth, Holger; Westneat, David F.; Wright, Jonathan; Araya Ajoy, Yimen Gerardo (Peer reviewed; Journal article, 2023)1. Assessing the biological relevance of variance components estimated using Markov chain Monte Carlo (MCMC)-based mixed-effects models is not straightforward. Variance estimates are constrained to be greater than zero and ... -
Differential Allocation in Parental Care - as a Strategy to Retain High Quality Partners
Rye, Kristian (Master thesis, 2017)The differential allocation hypothesis predicts a trade-off between current and future reproduction that is affected by the attractiveness of the current mate. Here, I present an individual-based simulation model where a ... -
Differential allocation of parental investment and the trade-off between size and number of offspring
Ratikainen, Irja Ida; Haaland, Thomas; Wright, Jonathan (Journal article; Peer reviewed, 2018)When parents decide how much to invest in current versus future offspring and how many offspring to divide their current investments between, the optimal decision can be affected by the quality of their partner. This ... -
Differential allocation revisited: When should mate quality affect parental investment?
Haaland, Thomas; Wright, Jonathan; Kuijper, Bram; Ratikainen, Irja Ida (Journal article; Peer reviewed, 2017)Differential allocation (DA) is the adaptive adjustment of reproductive investment (up or down) according to partner quality. A lack of theoretical treatments has led to some confusion in the interpretation of DA in the ... -
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 ... -
Distinguishing animal personality and innovation in the guppy - the effect of sex and body size
Berdal, Monica Anderson (Master thesis, 2015)How individuals within the same population show consistent differences in different behaviours, i.e. animal personalities, and how these correlate into a wider behavioural syndrome has become a hot topic in behavioural ... -
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 ... -
The ecological and evolutionary role of telomere length in house sparrows
Pepke, Michael Le (Doctoral theses at NTNU;2021:420, Doctoral thesis, 2021)Telomeres, the DNA sequences capping the ends of linear chromosomes, are ancient molecular structures that are shared among most eucaryotes. The telomeres protect chromosomes from degradation and are vital to genome ... -
Effects of energetic state and social environment on individual foraging strategies in a population of house sparrows, Passer domesticus
Guldvik, Martin (Master thesis, 2023)Hvordan variasjon i adferd blant individer som er del av samme populasjon or er utsatt for de samme seleksjonstrykkene blir vedlikeholdt, er ennå uvisst blant evolusjonsbiologer, siden de forventes å ha utviklet de samme ... -
Effects of environmental variation on the evolution of pure, conditional and learned social foraging strategies
Brady, Micah Allen (Master thesis, 2024)The behavior of animals is influenced by genetic and environmental factors as well as the interactions between the two. It is also influenced by the behavior of others. The Producer-Scrounger model is a classic model that ...