Sun, G.-Z., Huang, B., Guan, Z.-H., Geissmann, T., and Jiang, X.-L. (2011). Individuality in male songs of wild black crested gibbons (Nomascus concolor). American Journal of Primatology 73: 431-438.

Individuality in male songs of wild black crested gibbons (Nomascus concolor)

Guo-Zheng Sun^1,2, Bei Huang^1,2, Zhen-Hua Guan^1,2, Thomas Geissmann³, and Xue-Long Jiang<sup>1

1</sup> State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
² Graduate School of Chinese Academy of Sciences, Beijing, China
³ Anthropological Institute, University Zürich-Irchel, Zürich, Switzerland

Abstract
This is the first study of vocal individuality in male songs of black crested gibbons. The sound recordings were carried out at two field sites, Pinghe, Ailao Mountains, and Dazhaizi, Wuliang Mountains, both located in Yunnan province, China. A total of 127 coda phrases of 38 male songs bouts of eight individual male gibbons were analyzed. Stepwise discriminant function analysis was used to examine the acoustic individuality of the males. We found that individuality among neighbors was very pronounced. Moreover, individuality within a site (i.e. among neighbors) is higher than among individuals between sites. Our finding suggests that black crested gibbons may actively increase their degree of vocal individuality against that of their immediate neighbors by vocal adjustment.