My research investigates the mechanisms of energy balance in mammals that hibernate (hibernators). Hibernators are fascinating animal models for studying energy balance as they have a tightly controlled cycle of obesity and anorexia that allows them to survive periods of food scarcity by dropping their body temperature to freezing and living off of their fat stores for months at a time. Their active season is quite short (3-5 months in some species), and during that active season animals have to reproduce, raise offspring, and re-fatten for the next hibernation season. One species of hibernator, the thirteen-lined ground squirrel, inhabits a wide swath of North America (from Texas in the south to Canada in the north) and as such is exposed to a wide variety of hibernating conditions over its species range. This summer’s research will be a continuation of last year’s, and will involve travel to field sites across this species range, live trapping of animals in Texas, Oklahoma, Kansas, Iowa, and Minnesota, and removal of previously implanted temperature data loggers. Students must be willing to travel, camp, handle live animals, and assist with surgeries in the field, as well as conduct enzyme immunoassays in the lab upon returning to campus and analyze body temperature data to look for differences in hibernation patterns across the latitudinal gradient.