Our group uses the distribution and stable isotopic composition of biologically-produced organic molecules that accumulate in the environment to study climatic and ecological changes in the recent geologic past, and to determine how human activities influence these systems today. We make particular use of compound-specific hydrogen isotope ratios of lipid biomarkers. The large natural variability in these lipid hydrogen isotope ratios facilitates their use as proxies for diverse processes, and they encode information about climate, ecology, and metabolism. We work to improve our mechanistic understanding of the controls on the stable isotope distribution of biomarkers and other organic geological proxies, and apply these tools to answer questions about past changes and modern carbon cycling. 

01 Oct, 2025 Welcome Elena! Elena Jovanovska started today as an Ambizione Fellow, hosted by the Organic Geochemistry group and co-hosted by the Animal Diversity and Evolution group. Elena’s project will investigate the evolutionary processes of adaptive radiation and the associated key innovations underlying rapid diversification in a unique assemblage of single-celled siliceous diatoms from the genus Diploneis inhabiting Lake Tanganyika, East Africa. 

15 Sept, 2025. Welcome Kelly! Kelly Tragash has just joined the Organic Geochemistry group as a PhD student. Kelly will work on soil mesocosms and soil cores from the Swiss Canopy Crane II site to improve our understanding of how soil microbes respond to drought, and the implications for carbon cycling in soils. 

7 Sept - 11 Sept, 2025: Members of the Organic Geochemistry group traveled to Porto, Portugal to attend the 32nd International Meeting on Organic Geochemistry. Group members presented data from lakes in Switzerland, New York state, and the tropical South Pacific, as well as the first results from our bacterial co-cultures. PhD student Antonia Klatt was recognized for her excellent talk with a student presentation award. Congratulations Antonia!