Fig. 3

Comparison of acoustic parameters among the studied species. Box plots show the median (center line), first and third quartiles (box edges), and range (whiskers) of the mean values per individual for each acoustic parameter. Standard deviations (SD) based on these individual means are reported in Table 1. Parameters shown are: (1) Inter dual pulse time (s), (2) Pulse duration 1 (ms), (3) Pulse duration 2 (ms), (4) Interval between paired pulses (ms), (5) Dominant frequency (Hz), and (6) Call duration (s). Call duration and P. courbina were excluded from statistical comparisons, because it is not known whether the calls were made by the same specimen; the latter is shown only for illustration and has no letter assigned. Different letters above boxes indicate statistically significant differences between species (Tukey post hoc test, p < 0.05).