Stable isotopes are non-radioactive forms of elements that share the same number of protons but differ in their number of neutrons. Although chemically identical, isotopes vary in mass, and those mass differences influence how they partition in physical, chemical, and biological systems. In this stream, we use those subtle differences to answer questions about environmental change and physiology. In particular, our lab focuses on two larger research questions:

1. Climate Change and Ruminant Metabolism

How did fluctuations in atmospheric carbon dioxide shape plant nutrition in the past? How did large herbivores such as the extinct Irish elk respond to these changes, and what might this mean for modern ruminants as carbon dioxide levels continue to rise? To explore these questions, we will design and build custom growth chambers to cultivate plants under controlled carbon dioxide concentrations, then feed those plants into an artificial digestive system that contains rumen fluid obtained from cows.

2. Fire, Smoke, and Human Evolution

How has smoke exposure influenced the evolution of human immunity and physiology? Using a rodent model, we will investigate how chronic smoke exposure activates immune defenses and alters the stable isotope composition of bone and soft tissue.

Students in this stream will gain hands-on experience in experimental design, electronics and soldering, animal handling, blood collection, stable isotope and DNA analysis, programming, and other interdisciplinary lab techniques. Independent projects are welcomed and encouraged within the broader goals of the lab.