The effects of posterolateral spine length and body length on feeding rate in the rotifer,Brachionus calyciflorus

The length of the posterolateral spines in the rotifer, Brachionus calyciflorus, is variable. The effect of the length of these spines on the clearance rates of B. calyciflorus was examined under laboratory conditions using radioactively-labelled yeast (Rhodotorula) and bacteria (Aerobacter). The hypothesis that individuals with longer spines have higher clearance rates than those of similarly-sized individuals with shorter spines was rejected. The effect of body length (L) on the clearance rates (C) of short-spined and long-spined animals was also examined. Statistically significant linear regressions of the form log₁₀ C = aL + b, were derived for both types. The slopes of both regressions were similar and suggest that clearance rate in B. calyciflorus increases as a cube function of body length.