Allometric scaling, metabolic body size and interspecies comparisons of basal nutritional requirements.

The amounts of specific substances needed per day that are generally thought to be nutritionally essential or conditionally important are similar among animal species when expressed per unit of energy consumed or per metabolic body size. Accordingly, a case is made that in addition to basal daily energy utilization, allometric scaling based on metabolic body size (3/4 power of mass or weight in kg) may be used to predict and compare basal nutrient requirements among widely varied species, as well as make comparative toxicological and other biological assessments and predictions. Furthermore, given the increasing evidence for allometric scaling for a broad range of biological phenomena (both empirical and theoretical) there is usually a good biological question to be answered when an organismal process deviates markedly from an allometric scale.