Abstract # 57:

Scheduled for Thursday, June 20, 2013 07:00 PM-09:00 PM: Session 9 (SG Foyer ABC) Poster Presentation


B. Moore1 and J. Taglialatela1,2
1Kennesaw State University, Department of Biology and Physics, Kennesaw, GA, USA, 2Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Atlanta, GA
     Chimpanzees produce manual communicative gestures that are used flexibly and intentionally produced. However, there has been relatively little research to determine if vocalizations are similarly used flexibly. One way to determine flexibility is to examine the contexts in which vocalizations are produced - vocalizations that are used flexibly would not be bound to a specific context or emotional state of the caller. We hypothesized that chimpanzee vocalizations would be restricted to specific contexts given that much of the data available on chimpanzee vocalizations indicate that they are fixed in both form and usage. Vocalizations were classified into one of 6 different vocal types, and contexts were divided into 9 different categories based on the behavior of the focal chimpanzee and social partners. A total of 184 vocal events produced by 17 individuals were quantified from previously recorded audio/video clips of chimpanzees interacting with conspecifics. Four of the six vocal types had a high (>50%) context-tie index (CTI; % of vocal events from each type produced in the most common context) suggesting that they are restricted to specific contexts. The most flexible vocal type was the scream (CTI = 32%), whereas the most restricted vocalization was the pant-grunt (CTI = 72%). The data suggest that some, but not all, vocalizations are closely associated with specific socio-behavioral contexts whereas others are used more flexibly by the chimpanzees.