[Female song in Passeriformes: An exception or the rule?]

We analyzed the occurrence of female song in different families of Passeriformes aiming to better understanding of evolutionary prerequisites of this phenomenon and its relation with species biological traits and patterns of main passerine groups dispersion. Examined are 18 complete families, two Turdidae subfamilies, and three Sylviidae subfamilies among songbirds, also 4 complete families and two Tyrannidae subfamilies among bronchophone birds. As the data obtained indicate, female singing had appeared independently in different Passeriformes families, both songbirds and bronchophone ones, and seems not to be ancestral for all birds of this order. We did not find any direct connection of female song phenomenon with sexual dimorphism, duet singing or lipochrome coloration.