Leslie Vosshall wants to understand how environmental cues and internal physiology work together to guide complex animal behaviors. Vosshall and her team study this problem in mosquitoes and humans, applying approaches in neurobiology, behavior, genetics, and genomics. Vosshall’s team uses CRISPR/Cas9 genome-editing tools to advance understanding of how the mosquitoes that spread dengue and yellow fever integrate sensory cues to hunt their human hosts. The team is also studying the rules that govern human olfaction, using data from the more than 3,000 normal subjects they have screened since 2002. This work has the potential to aid in the diagnosis of smell disorders.