Patterson / Oral

Words and pictures: use of symbolism by two lowland gorillas

Francine Patterson

     A female western lowland gorilla (Gorilla g. gorilla) named Koko began to learn American Sign Language (ASL) 27 years ago. Michael, a male western lowland, joined the project three years later. Both gorillas were taught sign language through a combination of modeling, molding, and imitation, frequently in combination with spoken English. Koko's acquisition and use of sign language almost immediately exceeded expectations. Her vocabulary development showed remarkable parallels to that of human children, both in pattern and in content (Bonvillian and Patterson, 1999; Patterson, 1978; Patterson and Cohn, 1991; Patterson, Tanner and Mayer, 1988). She has exhibited the hallmarks of human language use, for example, productivity, displacement, and transmission (Hockett, 1960; Patterson, 1978). Both gorillas are able to translate spoken words into sign, and can respond in sign to spoken questions. Recent, more detailed analysis of the structure of Koko and Michael's multiple-sign combinations ("sentences") is revealing consistencies indicative of grammatical rules (Patterson, et al, in preparation). In this talk, I will review Koko's cognitive and language development, and introduce some comparisons with that of Michael, who began learning sign language later in his childhood than did Koko. I will discuss plans for further analysis of the gorillas' language and related symbolic abilities. Finally, I will consider how these findings can shape and inform our understanding of our human selves.

Bonvillian, J.D., and Patterson, F.G.P. (1999) Early sign-language acquisition: comparisons between children and gorillas. In S. Taylor Parker, R.W. Mitchell, and H. Lyn Miles (eds.), The mentalities of gorillas and orangutans (pp. 240-264). Cambridge University Press.
Hockett, C.F. (1960). The origin of speech. Scientific American, 203, 88-96.
Patterson, F. (1978). Linguistic capabilities of a lowland gorilla. In F.C.C. Peng (Ed.), Sign Language acquisition in man and ape: New dimensions in comparative psycholinguistics. Boulder, CO: Westview Press.
Patterson, F., Tanner, J. and Mayer, N. (1988). Pragmatic analysis of gorilla utterances: Early communicative development in the gorilla Koko. Journal of Pragmatics, 12, 35-54.
Patterson, F.G.P., Cohn, R.H. (1991). Language acquisition by a lowland gorilla: Koko's first ten years of vocabulary development. Word, 41(2), 97-144.