Skip to main content
Dryad

Variation in the resource environment affects patterns of seasonal adaptation at phenotypic and genomic levels in Drosophila melanogaster

Beltz, Jack1; Bitter, Mark2; Goldfischer, August1; Petrov, Dmitri2; Schmidt, Paul1

Published Sep 05, 2025 on Dryad. https://doi.org/10.5061/dryad.t1g1jwtfr

Data files

Sep 05, 2025 version files 3.97 GB

Click names to download individual files

Abstract

Natural populations often experience heterogeneity in the quality and abundance of environmentally acquired resources across both space and time, and this variation can influence population demographics and evolutionary dynamics. In this study, we directly manipulated diet in replicate populations of Drosophila melanogaster cultured in experimental mesocosms in the field. We found no significant effect of resource variation on estimates of adult census size. Resource variation altered patterns of phenotypic and genomic evolution across replicate populations; however, we find that this effect is secondary to selection driven by the fluctuating seasonal environment. Seasonal adaptation was observed for all traits assayed and elicited genome-wide signatures of selection. In contrast, adaptation to the resource environment was trait-specific and exhibited an oligogenic architecture. This illustrates the capacity of populations to adapt to a specific axis of variation (the resource environment) without hindering the adaptive response to seasonal change. This, in turn, suggests that resource variation may be an important force driving fluctuating selection across natural populations, ultimately contributing to the maintenance of genetic and phenotypic variation.