Fig. 3. Values for the limit of supercooling for individual painted turtles collected at our field site in north-central Nebraska in September (four hatchlings from each of three clutches) and November (four hatchlings from each of four clutches). The turtles were placed into the experimental protocol the day after they were removed from the nests in which they completed incubation and hatched. The distribution of values for animals studied in September differs from that for turtles studied in November (Wilcoxon two-sample test, z=3.86, P<0.001). Data are from Packard et al. (2001).