Models for population-mean excretion N:P (log-transformed) versus population-mean whole-body N:P.

Tables show key statistics on model fits and regression slope without diet (left) and with diet (right). Without accounting for diet, there is no correlation between whole-body N:P and excretion N:P. After accounting for the effect of diet, the overall model fit improves and a significant, negative correlation between whole-body N:P and excretion N:P is evident.