Figure 1. Effects of temperature and DR on Drosophila mortality.

A: Mortality rates of flies housed at different temperatures. Age-specific mortality analysis of lifespan data from once-mated female flies was performed (n = 5146 at 27°C, n = 3843 at 18°C, n = 1540 switched from 27°C to 18°C and n = for the reciprocal switch). The initial rate of mortality (a) was statistically indistinguishable for flies chronically housed at either temperature but the rate of mortality increased with age (b, the slope of the mortality trajectory, was significantly different between the two groups (see text, Table S1). Switching flies between temperatures altered the mortality trajectory slopes but the age-specific mortality rates of the switched groups always remained distinct from those of the chronic groups.

B: Mortality rates of fully-fed flies or flies undergoing DR. Male flies were maintained on full feed (n = 1184) or DR (n = 1171) or switched between the regimes (n = 464 switched from control to DR, n = 515 for the reciprocal switch). Age-specific mortality analysis of lifespan data was performed and a Gompertz model was fitted to the linear portion of the mortality curves. The initial rate of mortality (a, the intercept with the ordinate) was significantly different in flies subjected to DR (see text, Table S2). Switched flies rapidly adopted the age-specific mortalities of flies on chronic feeding regimens.