Bacteria adapt to adverse environmental conditions such as energy-starvation by entering dormant states. The fuel sources that sustain this dormant majority have yet to be resolved. My recent work has demonstrated that aerobic soil bacteria survive by scavenging trace gases from the atmosphere. In doing so, they literally live on thin air. This scholarly project aims to determine the physiological roles and ecological significance of hydrogen, methane, and carbon monoxide scavenging. Combining pure culture, field, and microcosm studies, the project's goal is to extend studies of trace gas scavenging from single organisms to entire ecosystems, and in turn enhance understanding of soil microbial ecology and biogeochemical cycling.