Energy Budgets Can Explain Body Size Relations
Kooijman, S.A.L.M. 1986.
Energy Budgets Can Explain Body Size Relations.
J. Theor. Biol. 121: 269 - 282
Abstract
The size-dependence of some 20 physiological variables has been
derived from a rather simple model for energy budgets. This nine
parameter model is based on detailed observations on the growth and
reproduction at varying food densities, and has the state variables
size and storage. The size-dependence of some variables works out to
be different for animals of the same species as opposed to animals of
different species. The reproductive rate, for instance, tends to
increase with size for animals of the same species, but to decrease
with size for animals of different species. This is because the
parameter values are constants within a species, but vary in a size
dependent manner for animals of different species. Although growth at
constant food density is assumed to be of the von Bertalanffy type,
and routine metabolism to be proportional to size, respiration turns
out to be about proportional to size to the power 3/4, both within and
between species. The value of about 3/4 has frequently been found, but
it has always been thought to be incompatible with von Bertalanffy
growth.