Fig. 2. Residuals of free fatty acid (A), uric acid (B) and ß-hydroxybutyrate (C) levels from the analysis given in Table 1 versus the residuals of body mass loss after removing the effects of initial body mass and the duration of flight. This indicates whether an above- or below-average metabolite level was correlated with an above- or below-average body mass loss given the flight duration and initial body mass. Correlations were: (A) r=0.392, P=0.022, N=34; (B) r=0.633, P<0.001, N=35; (C) r=0.565, P<0.001, N=35.