Thermoregulation

Thermoregulation is an organism's ability to keep its body temperature within a workable range even when the surrounding temperature is very different, ranging from animals that hold a fairly constant internal temperature through their own metabolism to those that simply take on the temperature of their surroundings. It is a core part of homeostasis, the broader capacity of the body to hold stable internal conditions despite outside change. When thermoregulation fails at the high end the result is hyperthermia, and at the low end, hypothermia, which in humans follows a drop in core temperature below 35 degrees Celsius after prolonged cold exposure; some animals, such as hibernating bears or torpid bats, deliberately let their body temperature fall during dormancy to conserve energy. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/