Table 2.

Summary of the principal components analysis examining variation in the double-whistle and its relation to male mating success

Raw distribution (mean±s.d.)PC1PC2
Frequency difference578.1±106.6 Hz0.795–0.70
Relative time of termination0.70±0.11 s0.1810.873
Relative amplitude (scale 0–3)1.91±0.670.807–0.006
Proportion with DW0.68±0.260.357–0.769
Eigenvaluen.a.1.5831.219
Percentage of variance explainedn.a.39.630.4
Spearman correlation with mating successn.a.–0.1820.039
P-value for significance of Spearman correlationn.a.0.350.845
  • DW, double whistle; n.a., not applicable