Experimental evidence for the unit of bird song production

Abstract

An experimental procedure was developed to determine the real-time nature of birdsong production. In a given trial, a burst of strobed light, directed at a male zebra finch (Poephila guttata), was triggered at a random point in his courtship song. Repeated trials allowed the formulation of three rules governing song production: (1) A zebra finch can stop song production in the midst of song, (2) the motor unit for song production is quantal, and (3) the quantal unit of song production is largely identical to a syllable, as read off a sound spectrogram. The comparative generality of the rules was tested by replicating results with another two other oscine species, the song sparrow (Melospiza melodia) and the canary (Serinus canarius). The results place constraints on neural models of song production, and suggest invariance between the units of song perception and production. [Research supported by NIH and the Cary Charitable Trust.]