Fig. 1
From: Cultural conformity generates extremely stable traditions in bird song
Swamp sparrow song structure. a Spectrogram of a swamp sparrow song sung by an individual from the Hudson Valley population. Swamp sparrow songs consist of one syllable (red) repeated 10 or more times. Each syllable consists of 2-5 elements or notes. b–g Examples of different syllable types. b–d Show the syllables that make up the repertoire of the same individual whose song is shown in a. e–g Show three syllable types sung by other males in the population, illustrating both the considerable diversity in syllable structure found within a population, but also how, as a consequence of vocal learning, different individuals also sometimes share the same syllable-type (b, f)
