Adaptation Mechanisms of Drosophila melanogaster and Drosophila suzukii to Their Distinct Habitats

The Drosophila genus comprises over 2000 species worldwide, making it a valuable model for studying habitat selection and preference differences among species in specific ecosystems. This review focuses on the differences in habitat and chemical preference between Drosophila melanogaster, which inhabits overripe and decaying fermented fruits, and D. suzukii, which inhabits fresh and ripe fruits. First, we discuss habitat characteristics associated with differences in chemical preference between the two Drosophila species and examine the correlation between chemical attraction and sensory adaptations. In addition, considering the sequential production of various volatile compounds such as 2-phenylethanol, ethanol, and acetic acid during the fermentation and decay processes of fruits, we provide a molecular-physiological interpretation of the differences in chemical tolerance and tolerance-related gene expression. Furthermore, we propose a novel relationship between the immune response and chemical tolerance, offering new insights into the study of immune pathways in fruit flies. Building on recent findings, we outline future directions for research into the molecular mechanisms of chemical interactions and adaptive strategies of D. melanogaster and D. suzukii.