Fig. 2 a, b.

A change in median lifespan does not always reflect effects in late life. Survival curves for ad libitum-fed and caloric restricted (CR) C57BL/6 (B6), and obese/obese (ob/ob) mutant mice are presented (reprinted from Harrison et al. 1991). On the left (a) is the curve to the median survival point, while the entire survival curve on the right (b) shows a very different trend in the last half of the lifespan