ABSTRACT
One of the earliest problems that confronted man was survival and protection against the extreme ranges of environmental temperatures. Although lower forms of animals, such as the poikilotherms and even some mammals (through mechanisms such as hibernation) are able to tolerate a wide range of environmental temperatures, man is dependent mostly on behavioral modification and autonomic regulation to maintain a narrow range of normal core body temperature. As such, when these two mechanisms are impaired, as in the aging individual and those with chronic illnesses, temperature-related events pose a major threat to survival.
