Fig. 6. (A) Correlation between hovering flight mass-specific metabolic rate and hexokinase activity residuals (r²=0.29, F_1,12=4.85, P=0.048) obtained from the body mass relationships in Fig. 5. (B) The same relationship (non-significant in both cases) presented for independent contrast obtained from the cyt b phylogeny using gradual (filled circles) and speciational (open circles) models of character evolution.