Fig. 3: Syllable-type diversity.
From: Balanced imitation sustains song culture in zebra finches
a Example sonograms of a tutor–pupil song pair. Syllable types are color-coded by lines above them. Color lines above each syllable indicate clusters computed separately for tutor and pupil in b. Note that syllable types are bird specific and color codes have no correspondence between tutor and pupil, e.g., green, yellow, and black labeled syllable types in tutor song merged into a single type (yellow labeled) in pupil’s song. b 2D scatter plots of syllable acoustic features: duration versus mean pitch, mean frequency modulation (FM), or mean Wiener entropy (a measure of the width of the power spectrum). The color of each marker indicates its computed syllable-type (type = cluster in feature space). Colors of clusters correspond to syllable-type colors shown in a. c Histogram of syllable-type diversity, pooled across all birds. d Regression analysis between tutor and pupil syllable-type diversity, showing no significant correlation for pupils with high or low imitation similarity of their tutors. e, f Tutor syllable diversity is not correlated with pupil song imitation similarity (e), or influence of tutors on pupils (f). g–k Examples of five tutor–pupil pairs with syllable recombination, namely merging in pupil songs. Source data for this figure is in Supplementary Data File 1.
