Latitudinally structured variation in the temperature dependence of damselfly growth rates.
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.
Department of Ecology and Environmental Science, Umeå University, SE-90187, Umeå, Sweden. viktor.j.nilsson@gmail.com
Viktor
V
Nilsson-Örtman
Robby
R
Stoks
Marjan
M
De Block
Helena
H
Johansson
Frank
F
Johansson
D000220:Adaptation, Biological; D000818:Animals; D004777:Environment; D005060:Europe; D005260:Female; D005838:Genotype; D005843:Geography; D008297:Male; D063191:Odonata / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D013696:Temperature