Estrutura e organização de sistemas complexos de comportamento vocal em cinco espécies do Gênero Turdus (Aves, Passeriformes, Turdinae)

Abstract

Communication is essential for animal life maintenance. In birds prevails acoustic communication, the song is the sound emission that has the specific recognition function, can be repetitive and predictable or complex with variations levels between individuals conspecifics. The genus Turdus provides members with a melodious and varied song, as is the case of five syntopic species in Brazil (T. leucomelas, T. rufiventris, T. fumigatus, T. amaurochalinus and T. albicollis), the high variation level may to cause recognition confusion of these species among experienced researchers and lovers in the listening birds practice. The structure analysis and complex organization of communication systems can give us answers to their functionality. In present study we gathered recordings of 72 individuals of five species above mentioned, from various localities, identified and named each of the 4826 notes, the song units of sound, and we measure their physical parameters. Through mathematical tools based on the theory of information verified the individual predictability of the corner and use as a criterion for comparison between individuals and species. We analyzed the data, sketched sequences and synthesized the results of cluster analysis to define the structure and organization of the song. The analyzes showed similarity in the song complexity of species compared some specific patterns were observed, such as T. amaurochalinus showed the highest values of the rhythm of the song and the maximum frequency of the notes, T. albicollis stood out by low values of these parameters, as for T. leucomelas, T. rufiventris and T. fumigatus was not observed characteristics, the three species show great variation in the parameters analyzed. But the evolutionary success of these species makes it clear that their songs are successful to exercise the functions of communication and specific recognition.