LPC spectrograms and formants, by VLS class.

<p>The panels show LPC spectra for all frames. The white bars approximate the boundaries between sexes (thick bar, Grunt panel) and individual animals (although given our sliding window procedure with frames overlapping, the actual boundary is typically internal to the frames both preceding and following each bar). Frames were selected for further use when both F1 and F2 were detected by LPC (within plausible ranges) and were within ± 3 standard deviations of their class means; those frames are indicted by a dot for F1 and an open circle for F2 at their measured frequencies in those frames. The acoustic results reported were calculated from the frames thus selected. See the supplemental section for additional details on these LPC analyses.