Impacts of larval environment on the adult dispersal syndrome

Dispersal is a fundamental process usually facilitated by suites of correlated traits. Phenotypic plasticity has the potential to change the structure of these dispersal syndromes depending upon the environmental context. Plasticity can take different forms, including time-delayed effects generating phenotypic variation dependent on past environmental conditions. Such carry-over effects have to be considered when estimating the lability of dispersal syndromes and the adaptiveness of dispersal. Here, we exposed caterpillars of the Large white butterfly Pieris brassicae from eight families to four density levels and three diet types in a full-crossed experimental design. We measured both larvae’s immediate physiological and behavioral plasticity and carry-over effects on adults’ traits involved in a dispersal syndrome. Significant immediate plasticity was detected on all caterpillars’ traits, whereas only a single marginal carry-over effect was detected on adult traits. Yet, we observed a dependency on larval environment of the correlations among adult’s traits and so of the dispersal syndrome. We relate these results to the species characteristics and discuss their consequences for spatial dynamics.