Testing effects of plant community diversity on host breadth evolution in armored scales.

Each plant-feeding insect species eats only some of the plant species in their environment. Host plant breadth varies widely across plant-feeding insect species, and the causes of that variation are unclear. Certain aspects of plant communities, e.g. stability, may affect the evolution of host breadth in plant-feeding insects. In this study, we use a comparative phylogenetic approach to test ideas about how the species richness of plant communities affects host breadth evolution. We use armored scale insects as a model system, because their host associations are well known, and host breadth varies widely across species.