4pAB3. The hyena’s laugh as a multi‐informative signal.

Session: Thursday Afternoon, May 21

Author: Nicolas Mathevon
Location: ENES Lab, Univ. Jean Monnet, Saint‐Etienne, France, mathevon@univ‐st‐etienne.fr
Author: Aaron Koralek
Location: Berkeley, CA
Author: Steve Glickman
Location: Berkeley, CA
Author: Frederic Theunissen
Location: Berkeley, CA


Many social mammals use vocalizations to encode information about sex, kinship, individual identity, and morphological cues, as well as motivational and physiological states. In spite of the importance of this multi‐informative signaling for the maintenance of social groups, most investigations on information coding in vocal signals have focused on only one cue; e.g., individual identity. Using the opportunity of the captive colony of spotted hyenas Crocuta crocuta at the Field Station for the Study of Behavior, Ecology, and Reproduction (University of California, Berkeley), we recorded and analysed the hyena’s giggle, one of the most well known calls of this large social African mammal. The acoustic analysis in both temporal and frequency domains was automated using a MATLAB customized routine. The fundamental frequency was tracked using two methods (cepstrum and autocorrelation) followed by a best guess using a Bayesian approach. The differences between giggles from different individuals or groups of individuals were assessed running a multiple analysis of variance (MANOVA in MATLAB), cross‐validated by a permuted discriminant function analysis (pDFA, R software). The results show that the hyena’s laugh encodes information about age, dominance status, and individual identity, giving to receivers some cues to assess the social position of an emitting individual.