Fig. 3. Rates of O₂ consumption (ml day^-1) of pelican embryos and hatchlings in relation to incubation age (days). Embryos incubated at 35°C pipped and hatched 1 day later than those incubated at 36°C, but data were not significantly different and were therefore combined up to day 30 (solid lines). Data for pipped embryos and hatchlings from the 35°C group are indicated by dashed lines on days 32-34. Internally pipped embryos are represented by filled symbols (triangles and diamonds for 35°C and 36°C groups, respectively), externally pipped embryos by open symbols (as for internal pipping) and hatchlings by open circles. Error bars represent 95% confidence intervals of the mean on each day.