Apr 18, 2014
Can Koko, Washoe, and other primates acquire language? (Hint, the answer’s no.) Read Terrace, Petitto, Sanders, & Bever (1979), learn why language is a human thing!
Researchers in the 1970s worked with chimpanzees and gorillas in attempts to teach them various artificial and natural visual languages. They theorized that although apes cannot produces the vocalizations necessary for human spoken language, an accessible visual language, such as a sign language, may allow apes to acquire human language. Though previous attempts at teaching language to apes yielded successful learning of words, apes lack the ability to use grammar to produce sentences and create new meaning. In this study, a chimpanzee Nim Chimpsky (Nim), was raised in a house with adult researchers who communicated with him and one another only using ASL from the age of two-weeks. However, even as his vocabulary increased, the complexity of his sign-combinations never progressed in the manner that is typical for a child’s language development. Looking at the results of this and previous studies with apes, it appears that many utterances that are sentence-like are prompted by signs immediately preceding the ape’s production of the signs or are encouraged by the researchers’ behaviors. Though apes and chimps can learn vocabulary, they cannot combine them to create new meanings, which is a hallmark of human language.
Can an Ape Create a Sentence? Terrace, Petitto, Sanders, & Bever (1979). Science, 206 (4421), 891-902. Please see Petitto’s published papers and abstracts here.
Keywords: Language Acquisition, modality