Latitudinally structured variation in the temperature dependence of damselfly growth rates |
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Authors: | Viktor Nilsson‐Örtman Robby Stoks Marjan De Block Helena Johansson Frank Johansson |
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Affiliation: | 1. Department of Ecology and Environmental Science, Ume? University, , SE‐90187 Ume?, Sweden;2. Laboratory of Aquatic Ecology and Evolutionary Biology, University of Leuven, , BE‐3000 Leuven, Belgium;3. Centre of Excellence in Biological Interactions, University of Helsinki, , PO Box 65 00014 Helsinki, Finland;4. Department of Ecology and Genetics, Uppsala University, , SE‐75236 Uppsala, Sweden |
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Abstract: | The Metabolic Theory of Ecology predicts that the slope of the rate–temperature relationship, E, remains consistent across traits and organisms, acting as a major determinant of large‐scale ecological patterns. Although E has recently been shown to vary systematically, we have a poor understanding of its ecological significance. To address this question, we conducted a common‐garden experiment involving six damselfly species differing in distribution, estimating E at the level of full‐sib families. Each species was sampled throughout its latitudinal range, allowing us to characterise variation in E along a latitudinal gradient spanning 3600 km. We show that E differs among populations and increases with latitude. E was right‐skewness across species, but this was largely an artefact of the latitudinal trend. Increased seasonality towards higher latitude may contribute to the latitudinal trend in E. We conclude that E should be seen as a trait involved in local adaptation. |
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Keywords: | Environmental variation growth rate metabolic theory of ecology thermal dependence universal temperature dependence |
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