RT Journal Article SR Electronic T1 Behavioral and genomic sensory adaptations underlying the pest activity of Drosophila suzukii JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.10.15.341594 DO 10.1101/2020.10.15.341594 A1 Sylvia M. Durkin A1 Mahul Chakraborty A1 Antoine Abrieux A1 Kyle M. Lewald A1 Alice Gadau A1 Nicolas Svetec A1 Junhui Peng A1 Miriam Kopyto A1 Joanna C. Chiu A1 J.J. Emerson A1 Li Zhao YR 2020 UL http://biorxiv.org/content/early/2020/10/15/2020.10.15.341594.abstract AB Studying how novel phenotypes originate and evolve is fundamental to the field of evolutionary biology as it allows us to understand how organismal diversity is generated and maintained. However, determining the basis of novel phenotypes is challenging as it involves orchestrated changes at multiple biological levels. Here, we aim to overcome this challenge by using a comparative species framework combining behavioral, gene expression and genomic analyses to understand the evolutionary novel egg-laying substrate-choice behavior of the invasive pest species Drosophila suzukii. First, we used egg-laying behavioral assays to understand the evolution of ripe fruit oviposition preference in D. suzukii as compared to their closely related species: D. subpulchrella and D. biarmipes, as well as D. melanogaster. We show that D. subpulchrella and D. biarmipes lay eggs on both ripe and rotten fruits, suggesting that the transition to ripe fruit preference was gradual. Secondly, using two-choice oviposition assays, we studied how D. suzukii, D. subpulchrella, D. biarmipes and D. melanogaster differentially process key sensory cues distinguishing ripe from rotten fruit during egg-laying. We found that D. suzukii’s preference for ripe fruit is in part mediated through an aversion to acetic acid and preference for stiff substrates. Lastly, we identified candidate genes involved in D. suzukii’s ability to seek out and target ripe fruits. Our results provide detail to the stepwise evolution of pest activity in D. suzukii, indicating important cues used by this species when finding a host, and the molecular mechanisms potentially underlying their adaptation to a new ecological niche.Competing Interest StatementThe authors have declared no competing interest.