Table 1. Acoustic properties of bouts and units: grand means and coefficients of variation (CVs).
| Acoustic property |
|
|
Grand mean ± SD |
|
|
| Bout duration (s) | - | 80.8 (24.0–135.8) | 3.2±1.6 (1.2–5.2) | 50.1 | 0.6 |
| Number of pulses per bout | - | 85.9 (52.2–129.9) | 4.8±2.1 (1.2–7.1) | 42.6 | 0.5 |
| Number of tonal segments per bout | - | 55.5 (35.1–100.7) | 1.6±0.5 (1.2–2.5) | 29.1 | 0.5 |
| Pulse rate (1/s) | - | 55.7 (37.7–98.6) | 1.8±0.6 (1.0–2.8) | 32.0 | 0.6 |
| Tonal rate (1/s) | - | 74.4 (31.7–112.7) | 1.1±0.6 (0.3–1.9) | 54.4 | 0.7 |
| Pulse duration (ms) | 32.4 (0.0–102.2) | 33.9 (18.0–85.4) | 58±16 (33–76) | 27.3 | 0.8 |
| Pulse peak frequency (Hz) | 17.8 (0.0–63.9) | 20.0 (6.9–28.2) | 60±6 (51–72) | 10.1 | 0.5 |
| Tonal duration (ms) | 37.4 (6.7–88.2) | 43.5 (27.8–62.1) | 461±120 (279–713) | 26.0 | 0.6 |
| Tonal fundamental frequency (Hz) | 8.3 (0.1–18.6) | 6.6 (1.6–13.9) | 168±14 (147–192) | 8.4 | 1.3 |
| Tonal fundamental frequency I | 15.4 (0.3–67.4) | 14.7 (9.1–36.9) | 194±23 (155–229) | 11.7 | 0.8 |
| Tonal fundamental frequency C | 13.0 (1.0–45.6) | 12.3 (1.7–23.3) | 219±18 (199–254) | 8.3 | 0.7 |
| Tonal fundamental frequency F | 13.0 (0.0–47.3) | 13.6 (2.1–23.4) | 210±24 (182–257) | 11.6 | 0.9 |
| Tonal frequency modulation (C-I) | 58.4 (2.1–136.0) | 60.1 (30.2–82.2) | 29±16 (13–62) | 53.9 | 0.9 |
| Tonal frequency modulation (F-C) | 84.8 (20.7–149.2) | 85.5 (38.6–134.4) | 23±9 (9–36) | 37.6 | 0.4 |
| Tonal frequency modulation (F-I) | 81.2 (2.7–139.5) | 77.2 (59.9–105.6) | 31±19 (10–70) | 62.3 | 0.8 |
| Pulse-pulse interval (ms) | 91.3 (11.5–199.5) | 76.3 (43.2–109.9) | 608±384 (184–1,341) | 63.1 | 0.8 |
| Pulse-tonal interval (ms) | 142.1 (32.6–200.0) | 178.7 (88.4–300.0) | 56±66 (0–181) | 118.0 | 0.7 |
| Tonal-pulse interval (ms) | 60.7 (3.2–149.4) | 61.5 (15.9–141.4) | 406±202 (147–794) | 49.9 | 0.8 |
| Tonal-tonal interval (ms) | 82.8 (12.8–137.5) | 73.8 (16.2–137.1) | 1000±493 (501–2,217) | 49.3 | 0.7 |
: mean within-bouts coefficient of variation ( = mean of the 78 bouts' CVs; Fig. S2a); 
: mean within-individual coefficient of variation ( = mean of the 10 individual CVs; Fig. S2b); Grand mean: mean of the 10 individual means, each obtained as the mean of the bouts' means (Table S5); CVb: between-individual CV; 
: between-individual to within-individual CV ratio; ranges in parentheses.