A toolkit for the dynamic study of air sacs in siamang and other elastic circular structures
Fig 8
Relation between air sac inflation for a boom call, with acoustics of bark immediately following the boom.
The top panel shows the relationship between the last observed radius of the air sac during a boom call, plotted against the subsequent bark’s acoustic parameters. A) shows the results for the acoustic parameter mean sound amplitude, which does not relate to the inflation of the air sac in this case. B) shows the relation of the mean spectral centroid (given in Hertz) of the bark relative to the inflation of the preceding boom. In C), correlation estimates are shown for the suite of acoustic parameters included in these exploratory analyses, but only statistically significant correlation coefficients are shown. Mean values and minimum and maximum values of the acoustic parameters in the bark were tested against the radius of the last boom.