Fig. 4: The received signal-to-noise (SNR) at which each group behaviorally responded (red circles) across the tested frequencies, the SNR minimum response level (blue crosses and line), and odontocete critical ratios (black diamonds and black line).

Frequency-dependent response signal-to-noise ratios (SNRPSD, red circles) at which groups behaviorally responded and the associated MRL curve (blue line) calculated across all trials, taken as a mean of the lowest two SNRPSDs for each frequency. Also shown is the power equation fit to the aggregate data for odontocete critical ratios (taken from 42; black line).