By Ursula Biba
Base metabolism, the minimum energy an organism uses to stay alive, differs based on mass. Though it was known that smaller animals burn more calories/ kilogram/ time, scientists have been developing mathematical models to quantify the differences in base metabolism since 1883. Previously, the most accepted models were Kleiber’s Law and West’s fractal model. Kleiber’s 1932 law states that base metabolism varies proportionately to mass raised to the power of ¾, while West’s 1997 model showed that the ¾ exponent did not fit all organisms. Recently, scientists at the Universitat de València, Universidad Politècnica de Madrid and Queen Mary University of London have devised a new model to explain these discrepancies. Using an astrophysics theoretical model, they found that the energy that West’s model did not account for the energy that dissipates like heat. The non-heat energy is used for cell division, synthesizing proteins, and other supportive functions. The new model states that metabolism is equal to a, a constant, times mass plus b, another constant, times mass to the 2/3 power—explaining the difference in base metabolism between different types of animals and even plants.
Asociación RUVID. (2018, February 11). Why base metabolism varies with mass. ScienceDaily. Retrieved February 13, 2018 from www.sciencedaily.com/releases/2018/02/180211130650.htm