Blair Wolf is a professor of biology and as an ecological physiologist-animal ecologist is interested in how animals cope with challenges of desert environments. Research in the lab is often directed at understanding how desert animals balance their water and energy budgets. Saguaro cacti in the Sonoran Desert, for example, produce a huge pulse of floral nectar and fruit and the importance of these resources to the bird and mammal communities can be quantified using carbon stable isotopes. Cactus tissues have a d13C values that differ greatly from most other plants in the community, which allows energy to be tracked from the cacti into the bird and mammal communities. Saguaros are thought to be “keystone” species and stable isotope approaches allow for actually quantifying the functional importance of cacti to consumers. Other work in the lab has used stable isotope methods to examine the diets of tortoises over their lifetimes by sampling scute rings; looked at the migratory origins of raptors and examine the allocation of nutrients to reproduction in reptiles.