Research article2020Peer reviewed
Does range expansion modify trait covariation? A study of a northward expanding dragonfly
Raffard, Allan; Therry, Lieven; Finn, Fia; Koch, Kamilla; Brodin, Tomas; Blanchet, Simon; Cote, Julien
Abstract
The adaptive value of correlations among phenotypic traits depends on the prevailing environmental conditions. Differences in selection pressures during species range expansions may therefore shape phenotypic integration. In this study, we assessed variation in behavioral and morphological traits, as well as their covariations, in replicated southern and northern European populations of the northward expanding dragonfly Crocothemis erythraea. Larvae from northern populations were, on average, darker in color, and therefore, better camouflaged than larvae from southern populations. However, there was no difference in activity level. Darkness and activity were positively correlated in larvae from northern populations, whereas this trait covariation was missing in southern populations. This suggests the emergence of alternative strategies in time-limited northern populations, a higher activity level that required better camouflage through darker coloration, while less active larvae benefited from an energy-saving strategy by reducing the investment in costly traits, such as body darkness. We further found that larger larvae emerged into larger adults, with a higher investment in flight morphology. Our findings imply that phenotypic integration is associated with the northward range shift, potentially differentially shaping fitness consequences, and ecological interactions in southern versus northern populations.
Keywords
Behavior; Climate change; Colonization; Growth-predation trade-off; Phenotypic architecture; Range expansion
Published in
Oecologia
2020, Volume: 192, number: 2, pages: 565-575 Publisher: SPRINGER
UKÄ Subject classification
Ecology
Publication identifier
DOI: https://doi.org/10.1007/s00442-020-04592-1
Permanent link to this page (URI)
https://res.slu.se/id/publ/110063