Novel Vocal Behavior



Current Research Project:  Gorilla Novel Vocal Behavior

It is widely believed that nonhuman apes lack the ability to voluntarily control their vocalizing (involving voiced sounds generated by vibration of the laryngeal vocal folds) and breathing and that they are unable to learn novel behaviors involving these functions. Yet recent evidence suggests that apes have more ability to learn and control their vocalizing and breathing than is traditionally considered. When spending time with Koko, one is quickly impressed by her breath control, apparent in her blow test ritual or in her pastime of blowing on musical wind instruments. In other contexts, one can observe Koko’s volitional control over novel vocal behavior too, as she “talks” into the phone, for example. It appears that Koko’s unique rearing history has facilitated the development of her extraordinary skills relating to vocal behavior and breath control.

The goal of this study is to record, describe and analyze the full range of Koko’s vocal and breathing-related abilities. The results have important implications for understanding the contribution of learning, interactive experience, and cultural environment in the development of complex vocal behavior like human speech.


Principal Investigator:  Dr. Marcus Perlman, Independent Researcher
Co-Investigators:  Drs. Penny Patterson and Ron Cohn, Gorilla Foundation Co-Founders

Next Steps:

Additional results will be incorporated into this study, reflecting the development of Koko's vocal/breath behaviors over the years, once some of the earlier analog video footage has been digitized.

Publications and Presentations:

1) "The Incorporation of Learned Vocal and Breathing-Related Behavior into the Multimodal Gestures and Rituals of an Enculturated Gorilla," presented at the Conference on "Embodied Language," at New College Oxford, on Sep. 26-28, 2011.


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