Life as we know it requires liquid water, which at extremely low temperatures exists as hypersaline brine. Using bacteria from Antarctic brines such as Don Juan Pond and Blood Falls, we investigate the adaptations that enable survival in cold, salty environments, and potentially on other worlds.

Blood Falls, an iron-rich outflow from beneath Taylor Glacier, provides access to Antarctic subglacial groundwater for ecological studies and serves as an analog for brine systems on Mars and icy moons.

We explore the limits of life in extreme environments, testing whether microbes can grow, metabolize, or persist under their in situ conditions, and how our laboratory findings translate to real-world potential, particularly when metabolic activity is difficult to detect.

Secondary metabolites are molecules secreted by organisms such as bacteria that mediate interactions with other microbes and the environment. We are interested in these metabolites as potential biosignatures, but also to understand how microbial communities are shaped by bacteria.

We collaborate with engineers to deploy cryobots such as NASA-funded University of Washington IceDiver and DLR-funded IceMole, that will advance our understanding of Earth’s cryosphere while developing technologies and mission operations for the search for life beyond Earth. These field campaigns simulate future autonomous cryobot missions to icy ocean worlds and expand the small global inventory of directly sampled subglacial lakes.

Mountains of the Cascade Volcanic Arc such as Mt. Baker in Washington and Mt. Meager in British Columbia, host active fumaroles that carve dynamic ice cave systems through overlying glacier ice. These volatile environments form extreme microhabitats for diverse subglacial microbes, filled with dangerously high concentrations of gases such as hydrogen sulfide and carbon dioxide, alongside striking deposits of sulfur and iron.