Kleiber's Law

Kleiber's law, named after Max Kleiber's biological work in the early 1930s, is the observation that, for the vast majority of animals, an animal's metabolic rate scales to the ¾ power of the animal's mass. Symbolically: if q₀ is the animal's metabolic rate, and M the animal's mass, then Kleiber's law states that q₀ ~ M¾. Thus a cat, having a mass 100 times that of a mouse, will have a metabolism roughly 31 times greater than that of a mouse. In plants, the exponent is close to 1.