Warm-blooded - Characteristics of Warm-bloodedness

Characteristics of Warm-bloodedness

Warm-bloodedness generally refers to three separate aspects of thermoregulation.

• Endothermy is the ability of some creatures to control their body temperatures through internal means such as muscle shivering or increasing their metabolism (Greek: endon = "within", thermē = "heat"). Some writers restrict the meaning of endothermy to mechanisms that directly raise the animal's metabolic rate in order to produce heat. The opposite of endothermy is ectothermy.
• Homeothermy is thermoregulation that maintains a stable internal body temperature regardless of external influence. This temperature is often, though not necessarily, higher than the immediate environment (Greek: homoios = "similar", thermē = "heat"). The opposite is poikilothermy.
• Tachymetabolism is the kind of thermoregulation used by creatures that maintain a high "resting" metabolism (Greek: tachys/tachus = "fast, swift", metabolēn = "throw beyond"). Tachymetabolic creatures are, essentially, "on" all the time. Though their resting metabolism is still many times slower than their active metabolism, the difference is often not as large as that seen in bradymetabolic creatures. Tachymetabolic creatures have greater difficulty dealing with a scarcity of food.