Figure 1.

Relationship between incubation temperature and sex ratio (proportion of males) for two species of tuatara. Curves (—) are the theoretical function of sex ratio upon incubation temperatures maximizing the likelihood for two experimental data sets: those where incubation temperatures deviated by ± 0.1°C (small error bars) or ± 1°C (larger error bars) from mean temperatures. The TRT_5–95% is indicated by the hatched lines and dashed lines are ± 2 SE.