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Fig. 7. Significant apnea can occur after song. (A) After a deep inspiration
following the song bout, respiratory movements cease for several seconds, as
indicated by air sac pressure (P) measurements. Oxygen consumption
rate (
O2) also
declines and remains at zero for 200 ms during apnea.
O2 increases
again as normal respiratory movements are resumed. (B) Tracheal airflow
(F), recorded simultaneously with air sac pressure in another
individual, confirms that apnea is correctly inferred from air sac pressure
patterns. Airflow is near zero for more than 1 s following the song bout.