Tachymetabolism

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.