Female responses to two-monitor control playbacks. Female responses to two-monitor control playbacks. Interpretation of axes and drawings as in Fig. 2. (A) Frog with animated vocal sac (VS infl.) versus a blank but powered-on screen (blank). (B) Frog with no vocal sac (no VS) versus a blank but powered-on screen. (C) Frog with animated vocal sac versus a gray square. (D) Frog with animated vocal sac versus a white square. Asterisks indicate female responses that were significantly different between the stimuli (proportion of females responding: binomial test; P=0.023 for D, all other cases P≥0.21; latency: ANOVA; P=0.023 for A, all other cases P≥0.30). Michael S. Reichert et al. J Exp Biol 2014;217:3254-3262 © 2014. Published by The Company of Biologists Ltd