Homeostasis literally means "same state" and it refers to the process of keeping the internal body environment in a steady state (Scott, 2004). Thus, homeostasis is a key element of species survival especially via regulation of its body temperature. This is true for all living beings since radical changes in their bodily temperature can bring about sickness or even death. "Animals that maintain a fairly constant body temperature (birds and mammals) are called homeotherms (also spelt homoiotherms); while those that have a variable body temperature (all others) are called poikilotherms. In humans temperature homeostasis is controlled by the thermoregulatory centre in the hypothalamus. (Scott, 2004)" The hypothalamus serves as the human body's regulatory system that balances body heat and maintain optimum condition depending upon climactic or weather conditions.
             Homeostasis is nature's way of ensuring that living things adapt or enable themselves to cope with their environmental conditions. When sudden atmospheric and environmental change occurs, the homeostatic process kicks in to enable the species' body to manage the change. When the change is too much to handle, the species dies or gets disease. This is already considered a radical event. Homeostasis has something to do with the thermoregulatory mechanism of a species' body. But the thermoregulatory functions can also become abnormal as a result of the following (Scott, 2004):
             Fever. Chemicals called pyrogens released by white blood cells raise the set point of the thermoregulatory centre causing the whole body temperature to increase by 2-3 °C. This helps to kill bacteria and explains why you shiver even though you are hot.
             Hibernation. Some mammals release hormones that reduce their set point to around 5°C while they hibernate. This drastically reduces their metabolic rate and so conserves their food reserves.
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