Crowd vocal learning induces vocal dialects in bats: Playback of conspecifics shapes fundamental frequency usage by pups
Acoustic parameters of bat calls during their development, at the ages of (A) 12–18, (B) 31–35, (C) 40–43, and (D) 48–51 weeks. The average for each bat (small symbols) and for each playback (large diamond) is presented. Blue represents the Low-F0 group (n = 5), red represents the High-F0 group (n = 4), and black represents the control group (n = 5). The axes were obtained by an LDA of the playbacks (see text for details), where the features that contributed the most were the F0, the energy entropy, and the spectral centroid (S1 Table). The axes of the 4 panels are the same as they were determined by the playbacks, and the playback location is constant in all stages. Numeric data are given in S1 Data. F0, fundamental frequency; LD1, first linear discriminant; LD2, second linear discriminant; LDA, linear discriminant analysis.