Broad research interests:

• Development and sustenance of habitability on Earth and other planets
• Evolution of marine and atmospheric redox chemistry throughout Earth’s history
• Biogeochemical cycling of nitrogen and inorganic carbon species
• Greenhouse gases and minerals as byproducts of microbial metabolism

Whiting mechanisms in meromictic Green Lake, Fayetteville, NY

Fine-grained calcium carbonate precipitation events called whitings are hypothesized to be a potential source of limestone muds throughout geologic history. Studying whitings confined at Green Lake in Fayetteville, NY indicates that biology may play an important role. [link to dispatch]

Nitrous oxide, chemodenitrification, and evolution during the Proterozoic Eon

Early life forms on Earth influenced the development of Earth’s nitrogen cycle, while nitrogen cycling dynamics simultaneously influenced the evolution of life. Coupled abiotic-biotic nitrogen cycling could have resulted in a nitrous oxide greenhouse during the Proterozoic, through chemodenitrification, shown here. Additionally, early nitrogen transformations could have been precursors to aerobic respiration pathways. Understanding early nutrient cycles can help us unravel how life evolved on Earth and can provide clues to how life could evolve on other planets. [link to publication]