Figure 3

PC1, PC2, PC3 by call type and population showing between-population variation in acoustic parameters within call types as well as variation among call types. Boxplots show the mean (middle horizontal bar), 25th percentile (lower bar), 75th percentile (upper bar), and outliers. Positive PC1 values refer to calls of higher frequency and shorter duration, while negative PC1 values refer to calls of lower frequency and longer duration. Positive PC2 values refer to calls with a larger range in frequency and higher entropy, while more negative PC2 values refer to calls with a smaller frequency range and lower entropy. Positive PC3 values refer to calls with more variation in frequency and amplitude, while more negative PC3 values refer to calls with less amplitude and frequency variation.