dc.contributor.advisor | Selbach, Christian | |
dc.contributor.author | Grenier, Gabrielle | |
dc.date.accessioned | 2023-11-07T14:10:53Z | |
dc.date.available | 2023-11-07T14:10:53Z | |
dc.date.issued | 2023-11-24 | |
dc.description.abstract | Across Arctic charr’s Holearctic distribution we see repeated patterns where multiple ecotypes diverge along ecological resource gradients. Arctic charr occur in both anadromous and lacustrine forms. Furthermore, lacustrine ecotypes are seen repeatedly specializing their morphology, trophic ecology, and life history along a benthic pelagic axis and along the depth gradient. Typically, a pelagic ecotype cooccurs with a profundal benthivorous ecotype. With increasing intraspecific diversity, a third piscivorous ecotype may also occur. These patterns of ecotype divergence occur in multiple lakes, therefore I studied if ecotypes occur in a random manner or if there is evidence for repeatability in their phenotypes. Life history was studied among five lakes to assess the repeatability of life history traits finding that variation in traits may be related to the number of ecotypes. The next study examined the repeatability and correlations among habitat use, diet, morphology, and life history. As these traits were found to be correlated differently in the ecotypes and at differing levels of intraspecific diversity, I propose the presence of an adaptive trait syndrome in Arctic charr ecotypes. Finally, in the anadromous Arctic charr I developed a method to quantify the number of marine migrations performed by an individual. These estimates of marine experience were discussed in relation to their influence on trophic ecology where there is increasing specialization with successive migrations. We also report an estimate of the number of marine migrations required for maturity in Arctic charr. This work demonstrates the importance of developing new methods and of studying diversity at a multi-trait level to improve our understanding of biodiversity and ability to manage and conserve species in accelerating climate change. | en_US |
dc.description.doctoraltype | ph.d. | en_US |
dc.description.popularabstract | All around the Arctic a fascinating phenomenon unfolds as Arctic charr, a remarkable fish species, reveals its secret evolutionary journey. These charr showcase a breathtaking display of ecological diversity across their habitat, diverging into multiple ecotypes along ecological gradients.
Picture this: Arctic charr can be found in two distinct forms - the adventurous anadromous charr that migrates between freshwater and marine environments, and the stable lacustrine charr that thrives exclusively in lakes. What's even more captivating is how these lacustrine charrs repeatedly specialize their appearances, eating habits, and life history along a resource and depth gradient in lakes. Some sport a pelagic lifestyle, while others prefer the depths, and yet others become skilled piscivores.
But are these intriguing patterns merely a coincidence, or is there a deeper, more profound meaning to them? To unravel this mystery, I researcher delved into five lakes to study the life history traits of these different ecotypes. What I discovered was that the variation in these traits could be linked to the number of ecotypes present.
Next, I set out to investigate the interplay between habitat use, diet, morphology, and life history in these fascinating fish. My findings were astonishing, as these traits exhibited varying degrees of correlation among the ecotypes and depending on the number of ecotypes present in the lake. This led to the intriguing concept of an adaptive trait syndrome, suggesting that each ecotype has developed a unique set of traits suited to their specific lifestyle depending on how many other ecotypes are present.
The enigma continues with the anadromous Arctic charrs, as the researcher devised a novel method to quantify the number of marine migrations undertaken by each individual fish. This marine experience was found to significantly impact their trophic ecology, resulting in a greater level of specialization with each successive migration. Moreover, the study provided valuable insights into the number of marine migrations required for maturity in anadromous Arctic charr.
This groundbreaking work sheds light on the importance of developing innovative research methods and studying biodiversity from a multi-trait perspective. As our world faces the challenges of accelerating climate change, understanding the intricacies of species adaptation and diversification is crucial for effective conservation and management.
Arctic charrs, with their mesmerizing array of ecotypes and unique adaptations, serve as a testament to the wonders of our natural world and the endless discoveries awaiting those who dare to explore its mysteries. | en_US |
dc.identifier.isbn | 978-82-8266-249-9 | |
dc.identifier.uri | https://hdl.handle.net/10037/31698 | |
dc.language.iso | eng | en_US |
dc.publisher | UiT The Arctic University of Norway | en_US |
dc.publisher | UiT Norges arktiske universitet | en_US |
dc.relation.haspart | <p>Paper I: Grenier, G., Smalås, A., Kjær, R. & Knudsen, R. (2021). Environmentally modulated repeat evolution of polymorphic Arctic charr life history traits. <i>Frontiers in Ecology and Evolution, 9</i>, 771309. Also available in Munin at <a href=https://hdl.handle.net/10037/24348>https://hdl.handle.net/10037/24348</a>.
<p>Paper II: Grenier, G., Knudsen, R. & Chavarie, L. Extent of repeatability of life history and related functional traits in polymorphic Arctic charr. (Manuscript).
<p>Paper III: Grenier, G., Knudsen, R., Jensen, H. & Power, M. Marine experience is related to trophic niche shifts, condition, and maturity in anadromous Arctic charr. (Manuscript). | en_US |
dc.rights.accessRights | openAccess | en_US |
dc.rights.holder | Copyright 2023 The Author(s) | |
dc.rights.uri | https://creativecommons.org/licenses/by-nc-sa/4.0 | en_US |
dc.rights | Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) | en_US |
dc.subject | Life history and repeatability of polymorphic Arctic charr | en_US |
dc.title | The intraspecific diversity of Norwegian Arctic charr (Salvelinus alpinus (L.)): An examination of repeatability and life history | en_US |
dc.type | Doctoral thesis | en_US |
dc.type | Doktorgradsavhandling | en_US |