Figure 3.

Shared motifs. (a) Examples of shared motifs (notes, or groups of notes) that occur across phrase types. Phrase numbers indicate performance order. Motif types are denoted by colours (red, blue and green). (b–d) Shared motifs: (b) in the order that the bird sang them (top to bottom) and (d) according to phrase type. (c) Enlargements of the first five phrases from (b), highlighting motif reuse. (e–g) Same as in b–d for a bird with a rich repertoire. Red boxes do not highlight every motif to avoid clutter.