Two laboratories interested in understanding cyclic physiological events related to different adaptive states of homeothermy will collaborate on comparative studies. Professor Michael E. Rashotte's laboratory in the Neuroscience Program at the Department of Psychology, Florida State University (Tallahassee, Florida, USA) and Professor Yuri F. Pastukhov's laboratory at the Sechenov Institute of Evolutionary Physiology and Biochemistry (St. Petersburg, Russia) are the participants. Each lab has extensive experience working on questions related to adaptive homeothermy, but one lab (Pastukhov) focuses on studies with mammals while the other lab (Rashotte) focuses on studies with an avian species. Their collaboration will provide each lab with the expertise to carry out comparative studies on the questions of interest using small mammals and avian species. The long-range objective is to make it possible for each lab to exploit species differences to answer fundamental questions about adaptive homeothermy.