Landscape context affects physiological but not genetic proxies of butterfly movement

Land-use change is a major driver of biodiversity loss, yet its effects on intraspecific variation in dispersal remain understudied. Dispersal influences species' persistence in fragmented landscapes, but whether agricultural landscapes filter individuals based on their dispersal is unclear. Our aim was to investigate whether fragmentation and reduced resource availability in agricultural landscapes can act as a filter favouring individuals with higher dispersal capacity. We sampled three butterfly species with different dispersal abilities (Maniola jurtina, Pieris napi, Thymelicus lineola) from agricultural and semi-natural grassland landscapes. We quantified intra- and interspecific variation in dispersal proxies (flight metabolic rate, body mass and wing size) combined with population genomic analyses to distinguish landscape filtering (spatial sorting), phenotypic plasticity and genetic adaptation. In M. jurtina, females from agricultural landscapes exhibited higher peak flight metabolic rates, body mass and more sustained flight. More sustained flight was also observed in P. napi, but no differences were detected in T. lineola. Despite phenotypic divergence, population genetic structure was weak, though elevated runs of homozygosity in two species suggested some inbreeding. Our results indicate that agricultural landscapes can filter dispersal-related traits at small spatial scales, with effects mediated by plasticity or spatial sorting rather than local genetic adaptation.