Henry is a stable isotope geochemist who is currently working with students on a wide range of research topics. These include: the nature of terrestrial climate during greenhouse periods of the past; reconstructing ecological relations between herbivorous dinosaurs, plants, and carnivorous dinosaurs of ancient North America and Madagascar; determining dietary preferences and migrational patterns of extinct animals such as dinosaurs and early mammals; estimating the elevation of western North American landscapes in the past; and constraining the provenance of humans remains and how movement of prehistoric human groups is related to other archaeological information.