KEY ISSUES IN THE STUDY OF PRIMATE ACOUSTIC SIGNALS.

Fast computers and relatively inexpensive software have caused a revolution in the field of digital signal processing and this will undoubtedly affect the study of human and primate bioacoustics. These new or updated tools, together with cutting edge techniques in sound analysis, are reviewed and introduced to readers, and examples are provided to give a better understanding of the topics. This paper looks at the study of nonhuman primate vocalisations. Language capacity in primates is now investigated more often than vocal communication in its acoustical form. However, several areas in the study of primate vocal communication are still poorly known and several effective techniques are still applied only rarely to the study of primate calls. We will review some recent papers dealing with primate vocal communication, discuss results, techniques and the implications for future studies. The topics range from The Source-Filter Theory of sound production to vocal registers, from formant analysis to non-linear phenomena and the implications for primate phylogeny.