The most diverse bee communities have the lowest levels of three common viral pathogens, according to a new analysis of thousands of native and nonnative bees. Researchers netted and trapped more than 4,000 bees from 60 species at winter squash farms across the state of Michigan, where both managed honey bee colonies and wild native bees pollinate the squash flowers. All but one species— Apis mellifera, the common European honey bee—are native bees. The number of bee species found at each farm ranged from seven to 49. Consistently, lower virus levels were strongly linked to greater species richness among the local bee communities, according to the study in the journal