Linguistics Encyclopedia.pdf

The linguistics encyclopedia 18
were given the same treatment during the nine months of Gua’s stay with the family. But
while Donald made the normal babbling sounds of a human infant, Gua restricted herself
to the barking, screeching, and crying noises of a young chimpanzee (Kellogg and
Kellogg, 1967).
Keith and Catherine Hayes’ experiment with the chimpanzee Viki met with more
success, relatively speaking. The Hayes took Viki into their home when she was just a
few days old and treated her as much as possible like a human child, Viki stayed with the
Hayes for six years and learnt to articulate four words, mama, papa, cup and up, with
difficulty, in a hoarse voice, and often in inappropriate contexts, so that it was unclear
whether she understood their meanings (Hayes and Hayes, 1952).
By 1968, there was conclusive evidence that human speech is not, in fact, a suitable
medium of communication for chimpanzees, for both behavioural and anatomical reasons
(Lieberman, 1968; Gardner and Gardner, 1971). This means that there is no more
justification for claiming that a chimpanzee cannot learn language because it cannot learn
to speak, than one would have for claiming that a fish cannot learn to move because it
cannot learn to walk—the fish simply has no legs, the chimpanzee simply does not have
the appropriate voice box.
Since chimpanzees in the wild use a form of gestural communication system naturally,
the Gardners, whose experiment with Washoe is probably the most famous chimpanzee
language experiment of them all, chose to exploit this ability, and taught Washoe to
communicate using American Sign Language (Ameslan), a language widely used in the
United States by the deaf. It consists of gestures made by the arms, hands, and fingers,
and the signs made are analogous to spoken words (see further SIGN LANGUAGE).
Project Washoe ran from June 1966 until October 1970 at the University of Nevada in
Reno. During this time Washoe learned to use over 130 signs correctly, both syntactically
and contextually, and to transfer her use of old signs to new situations.
Washoe was between eight and fourteen months old when the Gardners bought her
from a trader; they assumed that she was born in the wild and had lived with her natural
mother for several months until she was captured. The Gardners kept her in a caravan in
their back garden, and anyone who came into contact with her used only Ameslan in her
presence, both to communicate with her and with other humans, and since Washoe was
never left alone except when she was asleep, she was the subject of a total immersion in
Ameslan. She was taught by a mixture of a small amount of response shaping by reward,
guidance by the tutors on how to form the signs, and observation of the tutors’ signing
behaviour; the Gardners claim that the latter method accounted for the vast majority of
Washoe’s learning. Her acquisition pattern was like that of a child (see LANGUAGE
ACQUISITION). She began with manual babbling which was gradually replaced by true
signing. She began to combine signs into sentences when she was between 18 and 24
months, during the 10th month of the experiment, and her early two-word combinations
resembled those of children in subject matter. It appeared that a chimpanzee had finally
learnt some rudimentary language.
Two other chimpanzee experiments tended to confirm this ability of chimpanzees. In
one, a six-year-old chimpanzee, Sarah, was taught to communicate using pieces of plastic
of different shapes and colours to stand for words. The system was invented and the
experiment carried out by Premack and Premack (1972), who claimed that Sarah learnt a