A genomically tractable and ecologically relevant model herbivore for a model plant: new insights into the mechanisms of insectplant interactions and evolution

The availability of model microbial pathogens and plants has been key to characterizing resistance and virulence pathways and to shedding light on the mechanisms of host–parasite interactions and co-evolution (e.g. Allen et al. 2004, Science 306, 1957–1960; Bergelson et al. 2001, Science 292, 2281–2285). However, the absence of genetically tractable arthropod parasites of model plants has impeded so far our ability to gain better insights into the mechanisms, evolution and ecological consequences of plant–herbivore interactions. In this issue of Molecular Ecology, Whiteman et al. (2011) highlight fascinating features of a drosophilid fly, Scaptomyza flava, that feeds on the model plant Arabidopsis thaliana. They explore the potential of this system for studying insect–plant interactions with a clever mix of phenotypic and genetic experiments providing a comprehensive and persuasive argument for the validity of this model system. This study sets the ground for key developments in the unravelling of mechanisms involved in (i) plant–insect interactions and co-evolution, and (ii) transition to herbivory in arthropods and evolution of endophagous lifestyles.