DIMENSIONAL ANALYSIS AND ALLOMETRIC EQUATIONS CONCERNING COPES RULE

Cope's law deals with the phyletic increase in body size, both in inve rtebrates and vertebrates, and is based on paleontologic evidences and the qualitative morpho - functional advantages of living beings with greater body mass. In the present study we have applied dimensional an alysis, allometric equations, and a theory of biological similarity to submit Cope's rule to a quantitative test. When the allometric expone nt is equal or greater than unity (b greater than or equal to 1.0) the corresponding functions increase at a greater rate than body mass, im plying that larger species have a greater advantage for survival (figh t or flight). On the other hand, biological functions with allometric exponents lesser than unity (b < 1.0) are of vital importance when the corresponding function implies an economy of matter or energy. The su rvival of living beings of different body size under extreme environme ntal conditions is determined by functional reserves, such as water, s alts, and calories, which could also be defined in a quantitative mann er by means of allometric exponents (b). Finally, it is necessary to e mphasize that the present mechanistic approach of Cope's rule has a li mited validity since it ignores the incidence of many biological facto rs, such as population dynamics, evolutionary and ecological processes .