It has long been known that there is an allometric relationship between metabolic rate (M) and body weight (W) of the form: M = M0Wb. However, the debate remains open regarding the value of b. Only recently research turned to the ecological implications of existing differences in metabolic scaling among taxa. Using a data set on forest soil invertebrates, we evaluated the influence of differences in intraspecific metabolic rate scaling on observed species biomass and abundance distributions. We found that absolute densities and biomass were correlated with the exponents of the intraspecific metabolic scaling. Evenness of the abundance distributions and species diversity were also moderately linked to b. These results suggest that the shape of the intraspecific metabolic-rate—body-size relationship affects interspecific biomass and abundance distributions. This emphasizes the importance of intraspecific variations in allometric scaling and indicates the need to take these variations into account when proposing models to explain these relationships.