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Speciation reversal in European whitefish (Coregonus lavaretus (L.)) caused by competitor invasion
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Invasion of exotic species has caused the loss of biodiversity and imparts evolutionary and ecological changes in the
introduced systems. In northern Fennoscandia, European whitefish (Coregonus lavaretus (L.)) is a highly polymorphic species
displaying adaptive radiations into partially reproductively isolated and thus genetically differentiated sympatric morphs
utilizing the planktivorous and ...
Ecological speciation in postglacial European whitefish: rapid adaptive radiations into the littoral, pelagic, and profundal lake habitats
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
Understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. Postglacial fishes are
excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete ...
Discrete foraging niches promote ecological, phenotypic, and genetic divergence in sympatric whitefish (Coregonus lavaretus)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
Natural populations often vary in their degree of ecological, morphological and genetic divergence. This variation can be arranged along an ecological speciation continuum of increasingly discrete variation, with high inter-individual variation at one end and well defined species in the other. In postglacial fishes, evolutionary divergence has commonly resulted in the co-occurrence of a pelagic and ...
Contrasting Population and Life History Responses of a Young Morph-Pair of European Whitefish to the Invasion of a Specialised Coregonid Competitor, Vendace
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
Invasions of non-native species represent a global problem of great scientific interest. Here we study in detail the response in population and life history characteristics of closely related native species, with divergent habitat preferences, that are impacted by an invading species over a sufficient time period to allow a new stable state to become established. A time series of 20 years starting ...
A way forward with eco evo devo: an extended theory of resource polymorphism with postglacial fishes as model systems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-06-19)
A major goal of evolutionary science is to understand how biological diversity is generated and altered. Despite considerable advances, we still have limited insight into how phenotypic variation arises and is sorted by natural selection. Here we argue that an integrated view, which merges ecology, evolution and developmental biology (eco evo devo) on an equal footing, is needed to understand the ...
From clear lakes to murky waters – tracing the functional response of high-latitude lake communities to concurrent ‘greening’ and ‘browning’
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-21)
Climate change and the intensification of land use practices are causing widespread eutrophication of subarctic lakes. The implications of this rapid change for lake ecosystem function remain poorly understood. To assess how freshwater communities respond to such profound changes in their habitat and resource availability, we conducted a space‐for‐time analysis of food‐web structure in 30 lakes ...
Exploring trophic niches and parasite communities of sympatric Arctic charr and brown trout populations of southern Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-05-09)
Catchment-scale variation between lake habitats has the potential to simultaneously influence the trophic niche and parasite community of fish hosts. In this study, we investigated the trophic niche and parasite community of sympatric Arctic charr and brown trout populations from two inter-connected southern Norwegian lakes at different altitudes. Arctic charr and brown trout occupied profundal and ...
The effect of inter- and intraspecific competition on individual and population niche widths: a four-decade study on two interacting salmonids
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-12)
Competition is assumed to shape niche widths, affecting species survival and coexistence. Expectedly, high interspecific competition will reduce population niche widths, whereas high intraspecific competition will do the opposite. Here we test in situ how intra- and interspecific competition affects trophic resource use and the individual and population niche widths of two lacustrine fish species, ...
The role of gill raker number variability in adaptive radiation of coregonid fish
(Journal article; Tidsskriftartikkel; Peer reviewed, 2010-07-27)
Gill raker divergence is a general pattern in adaptive radiations of postglacial fish, but few studies have addressed the adaptive significance of this morphological trait in foraging and eco-evolutionary interactions among predator and prey. Here, a set of subarctic lakes along a diversifying gradient of coregonids was used as the natural setting to explore correlations between gill raker numbers ...
Transmission dynamics of the monogenean Gyrodactylus salaris under seminatural conditions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-07-12)
Tracking individual variation in the dynamics of parasite infections in wild populations is often complicated by lack of knowledge of the epidemiological history of hosts. Whereas the dynamics and development of Gyrodactylus salaris Malmberg, 1957, on Atlantic salmon, Salmo salar L., are known from laboratory studies, knowledge about infection development on individual wild fishes is currently sparse. ...