Modeling source-source and source-filter acoustic interaction in birdsong.

We present a simple model for birdsong production in Oscine songbirds that allows us to study the acoustic interaction between their two sound sources, as well as the acoustic coupling between sources and vocal tract. This model allows us to study complex phenomena in which the traditionally assumed source-filter separation hypothesis does not hold. We make testable hypotheses about the source of complexity in the song of some birds.