8.3 Academic arguments

Can primates acquire language?

Communication is an important part of animal behaviour. For example, primates use a variety of sounds and gestures in social interaction to portray threat, intention, alarm, and so on - and highly sophisticated forms of communication are found in other species as well (whales and dolphins provide a fascinating example). But, for many researchers this is not the same as human language which is essentially infinite in its meaning (largely due to its grammar), and which is able to associate specific (and abstract) meanings with arbitrary sound and symbols. Indeed, language is the thing that makes us uniquely human (or so the argument goes), and no other species comes close to emulating our ability to comprehend, use, and produce language.

But is language really unique to human beings? One problem with this theory is that other animals (including primates) cannot make our sounds. For example, they do not have the same fine control over their tongues, lips, and vocal chords, and are therefore unable to talk. Thus, if animals were to learn or understand language they would not be able to tell us. With this possibility in mind, Beatrice and Roger Gardner during the 1960s set about teaching a female chimpanzee (called Washoe) a version of American sign language used by deaf people. The Gardners began when Washoe was about one year old - and within three years she had developed a vocabulary of over 130 signs (or 'words'). Moreover, she learned to combine the signs to make simple sentences, and to use 'words' in creative and novel ways (e.g. after learning the verb 'to open' she would ask the investigators to 'open' the tap whenever she wanted a drink). Other researchers have confirmed these findings, and similar work has been undertaken with gorillas and orangutans.(Paterson and Linden 1981; Miles 1983)

However, the interpretation of these findings remains highly controversial. For example, some researchers have argued that these animals are not learning sign language per se, but rather they are only imitating the gestures made by their trainers. In support of this idea, they point out that primates often combine signs in illogical sequences and only occasionally join signs together in a meaningful way (which the trainer will inevitably then choose to reinforce). Others have argued that although primates might be able to communicate with language, there is little evidence to indicate that they can also use it as a vehicle for thought. But there are those who disagree. For example, some of the most compelling evidence for language in primates has come from Susan Savage-Rumbaugh and her colleagues who worked with a male pigmy chimpanzee called Kanzi. Apparently, this primate can understand about 150 English spoken words and can respond to complex and unfamiliar spoken commands such as 'throw your ball in the river' and 'go to the refrigerator and get out a tomato' (Savage-Rumbaugh 1990). Moreover, Kanzi can even use symbols to communicate past events, e.g. she pressed the symbols on a special keyboard to represent 'Matata bite' (Matata is a fellow monkey) to explain a cut that was on her hand.

These findings imply that language may not be unique human ability after all - although to put this work into its correct perspective, it needs to be borne in mind that Kanzi's language skills are only equivalent to that of a two-year-old human (Greenfield and Savage-Rumbaugh 1990). Thus, it still remains the case that no other species comes close to matching our ability to use and understand language. In other words, language is our natural medium of communication, although the same can clearly not be said of other animals.

(Wickens, 2000)