Fig. 2.

Change through the trial in a) Face, b) Eye and c) Comb temperature within treatment groups. Data at 0 on the x axis corresponds to baseline data. Confidence intervals are shaded around regression lines. Due to the large number of data points, the mean ± 1 S.E. per sampling day are instead shown for clarity. The shaded column indicates the skin temperature measurements collected in the 2–2.5 h immediately following enrichment withdrawal (not included in long-term analyses), to illustrate the short-term drop in temperature from baseline measurements in the barren group.