The behavioral ecology of animal vocal communication: An information theoretic approach

Innovative approaches for analyzing animal vocal communication are needed to investigate the behavioral ecology underlying the composition and structure of animal vocal communication systems. This approach will require a quantitative comparative analysis of animal vocalizations from different populations and species. To date, few studies have quantitatively examined vocal and repertoire structure in relationship to social or ecological strategies in populations of mammalian species. This lack of information has hindered our understanding of the behavioral ecology and evolution of mammalian vocal communication. We will present and discuss quantitative comparative measures from information theory that provide important insights into the ecological and social processes that shape the structure and organization of vocal repertoires. Information theory provides a powerful and efficacious approach because it links the physical, biological, and social properties of the environment to the structure of communication systems on multiple analytical and conceptual levels. Using two phylogenetically unrelated species as examples (i.e., bottlenose dolphins, squirrel monkeys), we will consider each level of communication, from the acoustic structure within call types to the complexity of call sequences, for a comprehensive approach toward animal vocal communication and its relationship to human language systems. [Work supported by NIH, Marine World Foundation, and SETI Institute.]