Fig. 1. Song bouts in zebra finches led to a distinct increase in the rate of oxygen consumption (
O2). Song is shown as an oscillogram in the bottom panel. The segment indicated by the grey horizontal bar in the bottom panel is also shown spectrographically in the top panel. The central panel shows the rate of oxygen consumption, and the vertical bars illustrate the delay between the onset of song and the increase in the rate of oxygen consumption. Horizontal bars indicate the approximate level of pre-song metabolic rate.
