Fig. 4. Effects of male abdominal immobilization on (A) thump, (B) scrape and (C) buzz seismic signals. Within individuals, peak intensities were normalized to the maximum intensity produced for all of the signal components. Normalized intensities were then averaged, and the relative dB difference between the treatments calculated. Graphs show relative dB difference between the treatments (control, experimental treatment and recovery) of all the individuals tested ± S.D. (N=5). Experimental treatments attenuated peak frequencies of all signals significantly (^**P<0.001; Tukey post-hoc test with Bonferonni corrections). No significant differences were observed between control and recovery treatments.