Subsyllabic motor gestures across species reveal principles of birdsong production

Birdsong exhibits a high degree of diversity across species, raising the question of how species-specific vocal repertoires emerge from the mechanisms underlying vocal production, and whether general principles of motor organization can be identified across species. We propose that a useful level at which to address this question lies below the syllable, in the organization of subsyllabic motor gestures. Using simultaneous abdominal EMG and air sac pressure recordings, we develop a physiologically grounded computational method to infer these gestures as building blocks for syllables. Across canary and zebra finch songs, the resulting gestures form structured clusters, revealing regularities at what we propose to be a fundamental level of vocal motor organization.