Associate Professor of Biology (Marine and Environmental Biology)
Steen is interested in how microbes live and eat on Earth. His research focuses on how they stay alive and eat in very low-energy environments, such as deep marine sediments and permafrost soils. These organisms appear to live for thousands of years in a state of near (but not total) stasis, a very different mode of life than the fast-growing microbes that dominate Earth’s surface. The Steen Lab uses bioinformatics, rate measurements, organic carbon characterization, and machine learning to reconstruct the lifestyles of these microbes, most of which resist growth in the lab. The group’s goal is to understand the physical and chemical environment of Earth microbes, their metabolic requirements and their environmental histories to better understand how they influence — and are influenced by — the Earth’s geochemical cycles.