Does range expansion modify trait covariation? A study of a northward expanding dragonfly
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.
KeywordsBehavior Climate change Colonization Growth–predation trade-off Phenotypic architecture Range expansion
We kindly thank the people that guided us to populations and helped collecting the samples: Yohan Morizet, Philippe Lambret, Charlotte Sohier, Hajnalka Gyulavári, Diana Goertzen and Frank Suhling. ANB-Belgium, Indre Nature, Grand Port Maritime de Marseille and Département Environnement et Aménagement provided permission and access to populations. This study is part of the project PROBIS (Biodiversa) and financially supported by ONEMA, DFG and SEPA. JC is supported by an ANR-12-JSV7-0004-01. JC and SB are part of the Laboratoire d’Excellence (LABEX) entitled TULIP (ANR-10-LABX-41).
Author contribution statement
LT, FF, SB and JC conceived and designed the experiment. LT, FF and KK conducted fieldwork and performed the experiment. LT and AR analyzed the data with input from SB and JC. LT wrote the first draft, AR wrote the revised version and all authors contributed to these versions.
Compliance with ethical standards
All applicable institutional and/or national guidelines for the care and use of animals were followed.
Conflict of interest
The authors declare they have no conflict of interest.
- Bauhus S (1996) Funde von Crocothemis erythraea (Brullé) und Aeshna affinis (Vanderlinden) in der Lippe-Aue (Anisoptera: Libellulidae, Aeshnidae). Libellula 15:79–84Google Scholar
- Bonner JT (2006) Why size matters: from bacteria to blue whales. Princeton Univ. Press., PrincetonGoogle Scholar
- Brockaus T, Roland H-J, Benken T et al (2015) Atlas der libellen Deutschlands (Odonata). Libellula Suppl 14:1–394Google Scholar
- Cordero A (1991) Fecundity of Ischnura graellsii (Rambur) in the laboratory (Zygoptera: Coenagrionidae). Odonatologica 20:37–44Google Scholar
- Deknijf G (1995) Crocothemis erythraea en Cercion lindenii, nu al in België en binnenkort ook in Nederland algemeen? Libellennieuwsbrief 4:7–12Google Scholar
- Dijkstra K-DB (2006) Field guide to the dragonflies of Britain and Europe. British Wildlife Publishing, DevonGoogle Scholar
- Dommanget JL (1987) Etude faunistique et bibliographique des Odonates de France. Secrétariat Faune/Flore ParisGoogle Scholar
- Hill JK, Griffiths HM, Thomas CD (2011) Climate change and evolutionary adaptations at species’ range margins. Annu Rev Entomol 56:143–159. https://doi.org/10.1146/annurev-ento-120709-144746 CrossRefPubMedGoogle Scholar
- Hodgetts RB, O’Keefe SL (2006) Dopa decarboxylase: a model gene-enzyme system for studying development, behavior, and systematics. Annu Rev Entomol 51:259–284. https://doi.org/10.1146/annurev.ento.51.110104.151143 CrossRefPubMedGoogle Scholar
- Lohr M (2003) Crocothemis erythraea auch in Niedersachsen (Odonata: Libellulidae). Libellula 22:35–39Google Scholar
- Ott J (2007) The expansion of Crocothemis erythraea (Brullé, 1832) in Germany – an indicator of climatic changes. In: Tyagi BK (ed) Biology of dragonflies. Scientific Publishers, JodhpurGoogle Scholar
- R Core Team (2013) R: A language and environment for statistical computing. R Foundation for Statistical Computing, ViennaGoogle Scholar