VOCAL PRODUCTION IN NONHUMAN-PRIMATES - ACOUSTICS, PHYSIOLOGY, AND FUNCTIONAL CONSTRAINTS ON HONEST ADVERTISEMENT

The physiological mechanisms and acoustic principles underlying sound production in primates are important for analyzing and synthesizing pr imate vocalizations, for determining the range of calls that are physi cally producible, and for understanding primate communication in the b roader comparative context of what is known about communication in oth er vertebrates. In this paper we discuss what is known about vocal pro duction in nonhuman primates, relying heavily on models from speech an d musical acoustics. We first describe the role of the lungs and laryn x in generating the sound source, and then discuss the effect; of the supralaryngeal vocal tract in modifying this source. We conclude that more research is needed to resolve several important questions about t he acoustics of primate calls, including the nature of the vocal tract 's contribution to call production. Nonetheless, enough is known to ex plore the implications of call acoustics for the evolution of primate communication. In particular, we discuss how anatomy and physiology ma y provide constraints resulting in ''honest'' acoustic indicators of b ody size. (C) 1995 Wiley-Liss, Inc.