Allometry is the study of the relative change in proportion of an attribute compared to another one during the growth of an organism. These attributes may be morphological, physiological, or otherwise.

In the exponential function module we showed how allometric equations are derived. In this section, we sill use allometric equations, which are power functions, in calculations. Our example is the relationship between insect body mass and resting metabolic rate.

The bee Ascosphaera apis. Photo credit: Stephen Ausmus courtesy of U.S. Department of Agriculture, Agricultural Research Service.

Niven and Scharlemann [1] found that insect resting metabolic rate (RMR) scaled positively with body mass (M) according to the equation,

RMR = 4.14 · M^0.66,

where M is measured in mg and RMR is measured in mm³ O₂ per hour.

[1] Niven, J.E., and J.P.W. Scharlemann (2005). Do insects metabolic rates at rest and during flight scale with body mass? Biol. Lett. 1: 346-349.