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.
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