1. Gut microbial ecology modulates fly health. Using gnotobiotic flies and a battery of physiological and fitness assays, we study the effects of gut microbial community ecology on host cell physiology.  
 
2. Metabolic crossfeeding influences community ecology of the gut microbiota. Using both gnotobiotic flies and high throughput in vitro growth assays, we study the microbial interactions that shape the fly gut microbiota. 
 
3. Stochastic population dynamics in the microbiome influence host physiology. We have developed single fly feeding and monitoring techniques to measure microbial populations in the gut. Using these approaches, we are studying basic principles of colonization and stability in the context of host physiology and disease ecology.