Resonant panting in pigeons

1. 1. The panting frequency and resonant frequency of the thoraco-abdominal complex were determined in nine domestic pigeons, Columba livia. 2. 2. When artificially ventilated with a constant driving force at frequencies from 2 to 19 c/s, maximum tracheal air flow occurred at the resonant frequency of the respiratory system. 3. 3. No significant difference was found between normal panting rates (10·2 c/s ± 0·22 S.E.) and the resonant frequency of the thoraco-abdominal complex (9·4 c/s ±0·45 S.E.). 4. 4. These data suggest that pigeons pant at the resonant frequency of the respiratory system, utilizing the mechanical-acoustical properties of the system to provide maximum air flow with least effort.