Acoustic similarity between disjunct populations of the Marsh Tapaculo Scytalopus iraiensis Bornschein, Reinert & Pichorim, 1998 (Aves: Rhinocryptidae)

This study investigated the vocalizations of Scytalopus iraiensis with the aim of identifying variations in vocalization between disjunct populations of the species. We analyzed 30 sound recordings of the species obtained from the Xeno-canto and Wiki Aves databases. The recordings were converted to the WAV format and then played back using Audacity software to obtain the following acoustic parameters: number of notes, duration, maximum frequency, and minimum frequency. After obtaining the parameters, Principal Component Analysis (PCA) was performed on the data in a smaller set of attributes. The PCA results were used in a correlation analysis, in which one of the variables that showed a high correlation (≥ 0.6) was excluded. After this process, the normality of the variables was verified using the Shapiro-Wilk test (p < 0.001), and those that did not meet the normality assumption were logarithmized. These data were associated with the records of each region and the similarity between the populations of the South and Southeast was assessed through a Permutational Multivariate Analysis of Variance (PERMANOVA). Our results showed that, despite the geographic isolation, the populations of S. iraiensis did not present significant variation in their vocalizations (RF = 0.7279, p = 0.425), indicating that the time they were separated was not enough to cause changes in their songs.