As the most ancient and diverse form of life, bacteria harbor the majority of the planet’s biomass, form the foundation of our biosphere, and generate more than half of the oxygen we breathe.   The number of bacterial cells on Earth (an estimated 10^30 to 10^31) out-number eukaryotic cells by several orders of magnitudes, and your own body contains ten times more bacterial cells than human cells.  Beneficial, symbiotic bacteria perform essential functions for many plants, animals, fungi, and protists and are woven into the evolutionary trajectories of these groups. Without bacteria, other organisms would not have evolved and could not survive today.

We study the evolutionary and ecological processes that shape bacterial diversity in the natural environment.  Much of our work explores how symbiotic interactions influence genome content and architecture, metabolic functions, and genetic diversity of the species involved.  Conversely, we also explore how genome-level changes can impact microbial functions and host interactions.   Our current work largely focuses on understanding the ecology and evolution of long-term mutualisms between bacteria and insects, most especially ants.

We use genomic approaches as tools to explore the microbial world and their symbiotic interactions.   Molecular datasets help us understand how and why bacterial genomes change over time, shed light on functional interactions between hosts and symbionts, and clarify the physiological and genetic diversity contained within complex microbial communities.  Our projects range from population genetic analyses to broad genomic comparisons across phyla.

Because we work at the intersections of environmental biology, evolution, and genomics, our lab at Duke is jointly part of the Nicholas School of the Environment and the Institute for Genome Sciences and Policy (IGSP).