I study molecular fingerprints of present and past microbial life and interactions of microbes with geochemical cycles and climate. My main tools are lipidomics via high-resolution mass spectrometry, compound-specific stable isotope analysis, experimental microbiology, phylogenetics and biochemical analyses.
I develop state-of-the-art analytical tools such as an in situ mass spectrometer to study greenhouse gas cycling in aquatic systems and their release to the atmosphere and the spooling-wire microcombustion-IRMS to reveal the isotopic systematics of organic compounds.
Chris studies how the carbon and hydrogen isotopic composition of archaeal lipids can be used as paleoenvironmental proxies.
Xiaoxiao studies how changes in the nitrogen cycle were coupled to climate change in the Paleogene and how different trophic levels in the ocean were impacted by these changes.