Figure 1.
Offspring sex ratios in relation to plasma hormone levels. (a) Group sex ratios produced during control (white) and hormone treatments (black). (b) Mean (+s.e.) changes in faecal concentrations of corticosterone (/10, black), testosterone (white) and 17β-oestradiol (hatched) from individual females between control and hormone treatment. Corticosterone was significantly elevated during treatment with corticosterone, and significantly lowered by metyrapone (ANOVA between groups with Tukey's pairwise comparisons: F5,39=11.02, p<0.001). 17β-oestradiol and fadrazole significantly raised and lowered 17β-oestradiol concentrations, respectively (F5,39=20.80, p<0.001), while testosterone treatment significantly raised faecal testosterone levels (F5,39=13.82, p<0.001). *p<0.05, **p<0.01, ***p<0.001.