HIBERNATION IN MAMMALS
Abstract
Natural hibernation is contrasted with induced hypothermia. In hibernation, the process is passive, with declines in respiratory rate, heart rate, and oxygen consumption preceding the drop in body temperature; in enforced hypothermia the animal chills in spite of a violent metabolic effort to remain warm. This control is demonstrated throughout hibernation; between ambient temperatures of about 4 and 15 C, the animal passively follows the environment, but if the temperature goes below 0 C the metabolic rate is increased and body temperature is maintained above freezing. The circulatory process in the arousing hibernator is followed. The arousing hibernator's circulatory control and ability to rewarm are in strong contrast to the animal undergoing induced hypothermia; in hypothermia almost all ability to rewarm is lost. It is shown that the hibernators have a specialization of temperature control which is unique among the vast array of mammals. However, the precise nature of the changes made during this resetting of the ''physiological thermostat'' is largely a mystery. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1961
- Accession Number
- AD0276436
Entities
People
- Charles P. Lyman