Figure 1.
Representative spectrograms of adult advertisement songs of S. teguina (top) and S. xerampelinus (bottom).
Table 1.
Species, sex (F/M) and population means (SD) for litter size and developmental landmarks in singing mice.
Figure 2.
Representative spectrograms of isolation calls from age-matched S. teguina (left) and S. xerampelinus (right).
Notes A-E are indicated to the right of the first note of that type in each spectrogram.
Figure 3.
Change in the proportional abundances of common notes types during vocal development in singing mice.
Representative examples of notes A–E (dominant frequency only; see Fig. 2 for harmonics) are shown on the X-axis. Black (S. teguina) and white (S. xerampelinus) bars are species means for notes in each age class. Error bars are +1 SE. Sample sizes by age class are 20 (1–3 and 30+ days), 19 (4–6 and 7–9 days) and 13 (10–12 days) for S. teguina, and 9 (1–3 days), 11 (4–6 days), 7 (7–9 days), 4 (10–12 days) and 8 (30+ days) for S. xerampelinus. Species differences in the proportional abundances of note types within age class were tested with one-way ANOVA, * P<0.05, **P<0.01.
Figure 4.
Species, population, and age differences in singing mouse vocalizations.
Plot of mean scores from the first (PC1) and second (PC2) principle components axes for age classes in S. xerampelinus (white), and in S. teguina split by population (Cartago, black; Boquete, gray). Age classes are indicated next to each point. PC1 explains 35% of the total variance with higher scores corresponding to higher frequency. PC2 explains 20% of the total variance with higher scores corresponding to larger bandwidth and longer notes. Error bars are +/−1 SE.
Figure 5.
Change in call frequency during vocal development in singing mice.
Black (S. teguina) and white (S. xerampelinus) circles are species means for maximum (Max, dashes), dominant (Dom, dots), and minimum (Min, dots and dashes) frequency in each age class. Error bars are +/−1 SE. Sample size for S. teguina in the 13–15 day age class is 9; no calls were recorded for S. xerampelinus in this age class. See Figure 3 caption for all other sample sizes.
Table 2.
Age-specific differences between S. teguina and S. xerampelinus in whole call and individual note measures of frequency and timing.
Table 3.
The effect of age on frequency, note usage, call length and note rate in S. teguina.
Figure 6.
Change in stereotypy during vocal development in singing mice.
Black (S. teguina) and white (S. xerampelinus) cicles are species means for the coefficient of variation in each age class. Error bars are +/−1 SE. Sample sizes by age class are 15 (1–3 days), 16 (4–6 days), 14 (7–9 days), 11 (10–12 days), 6 (13–15 days) and 18 (30+ days) for S. teguina, and 7 (1–3 days), 8 (4–6 days), 5 (7–9 days) and 6 (30+ days) for S. xerampelinus. There were insufficient data for S. xerampelinus in the 10–12 age class and no calls were recorded for the 13–15 age class.