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	Figure 1. Percentages of advertisement calls.Median ± interquartile ranges (n = 10 per treatment) for EE2 exposure concentrations of A) 296 µg/L, 2.96 µg/L and 29.6 ng/L and B) 29.6 ng/L, 2.96 ng/L and 0.296 ng/L. Statistical differences were determined using General Linear Mixed models (GLMM). Significant differences from solvent control (CTRL) are marked by asterisks (* p≤0.05; ** p≤0.01; *** p≤0.001).
	Figure 2. Spectrograms of advertisement calls.A) Advertisement call of an unexposed control male with six accentuated clicks at the beginning of the call, indicated by vertical arrows and B) advertisement call of an EE2 exposed male (2.96 µg/L) with no accentuated clicks at the beginning of the call.
	Figure 3. No. of accentuated clicks within male advertisement calls.Median ± interquartile ranges (n = 10 per treatment) for EE2 exposure concentrations of A) 296 µg/L, 2.96 µg/L and 29.6 ng/L and B) 29.6 ng/L, 2.96 ng/L and 0.296 ng/L. Statistical differences were determined using General Linear Mixed models (GLMM). Significant differences from solvent control (CTRL)+human chorionic gonadotropin (hCG) treatment are marked by asterisks (* p≤0.05; ** p≤0.01; *** p≤0.001).
	Figure 4. Duration of clicks of male advertisement calls.Median ± interquartile ranges (n = 10 per treatment) for EE2 exposure concentrations of A) 296 µg/L, 2.96 µg/L and 29.6 ng/L and B) 29.6 ng/L, 2.96 ng/L and 0.296 ng/L. Statistical differences were determined using General Linear Mixed models. Significant differences from solvent control (CTRL)+human chorionic gonadotropin (hCG) treatment are marked by asterisks (* p≤0.05; ** p≤0.01; *** p≤0.001).
	Figure 5. Reversibility of call modifications due to EE2 exposure.Median ± interquartile ranges (n = 10) of (A) no. of accentuated clicks and (B) duration of clicks within the advertisement calls before, during, and four and six weeks after EE2 exposure (at 2.96 µg/L). Statistical differences were determined using two-tailed Wilcoxon signed-rank tests for paired samples. To control for type I errors from conducting multiple tests, false discovery rate (FDR) was applied. Significant differences are marked by asterisks (* p≤0.05; ** p≤0.01; *** p≤0.001).

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