Age-Related Variability of the Pied Flycatcher (Ficedula hypoleuca) Song in Natural and Urban Environments A. E. Bastrikova, S. I. Gashkov, and N. S. Moskvitina Abstract The age-related variability of the frequency and structural–temporal parameters of the advertising song of Ficedula hypoleuca males in natural habitats and the urban environment were analysed. In the natural habitats, the... Continue Reading →