Modulation in Bird Sounds

Abstract

In describing variation both within and between individuals and species of birds the complexities in vocal pattern have caused many problems. Yet these complexities are useful not only in the study of the patterns themselves, but also for interpreting the functional anatomy of the sound producing structures, the nature of the message, and the relationships among the birds involved. This paper analyzes several bird vocalizations and interprets their patterns as the product of individual and interacting oscillators and sound modifying structures; it also suggests a model for the operation of the syrinx during sound production. To