Functional and Evolutionary Relationships of Vocal Copying Phenomena in Birds

Abstract

Vocal copying (vocal imitation, vocal mimicry, and vocal convergence) in birds is reviewed and synthesized by placing these phenomena in a functional and evolutionary framework. Confusion surrounding avian vocal copying has resulted from vague and inconsistently applied terminology, virtually no experimental field work, and a failure to consider vocal copying in an evolutionary perspective. Four categories of vocal copying are recognized herein: vocal appropriation, vocal imitation, vocal mimicry, and vocal convergence or nondivergence. Vocal mimicry, a vocalization that serves to deceive a signalreceiver, is the rarest of the four categories and has not been verified experimentally.