My research straddles the boundary of biology and geology. I am interested in understanding how the presence of life on earth influences Earth’s climate in the present and in the past. My research on the influence of life on modern climate focuses on the pathways that produce and remove the greenhouse gas methane from the atmosphere. My research seeks to understand how the alteration of the physical environment by life can be used to search for life elsewhere in the universe. I am currently an Associate Research Scientist at the Planetary Science Institute and a Senior Research Associate at the University of Arizona.