Fig. 1

Posterior means of baseline corticosterone measured in blood samples from birds captured at different times of day. Black points denote time intervals selected to partition data into sets of equal sample size (n = 23, 23, 23 and 24, respectively). Grey points sort data into sets of equal length in time (i.e. 4 sequential intervals of 158 min each; n = 19, 30, 25 and 19). Dispersion bars indicate 95 % credible intervals and suggest corticosterone levels obtained from the first sampling interval (2.018 ng/ml and 2.099 ng/ml) to be higher than those from the third interval (1.417 ng/ml and 1.434 ng/ml). Dispersion of posterior means from the second (1.977 ng/ml and 1.911 ng/ml) and fourth intervals (1.541 ng/ml and 1.494 ng/ml) overlap slightly with others. Log denotes the natural logarithm (to base e)