The idea of raising a chimp and a child together may seem like
a nightmare, but this is basically what was done in an early
attempt to teach a chimpanzee to use human language. In the
1930s, two scientists (Luella and Winthrop Kellogg) reported
on their experience of raising an infant chimpanzee together
with their baby son. The chimpanzee, called Gua, was reported
to be able to understand about a hundred words, but did not
“say” any of them. In the 1940s, a chimpanzee named Viki was
reared by another scientist couple (Catherine and Keith
Hayes) in their own home, exactly as if she was a human child.
These foster parents spent five years attempting to get Viki to
“say” English words by trying to shape her mouth as she
produced sounds. Viki eventually managed to produce some
words, rather poorly articulated versions of mama, papa and
cup. In retrospect, this was a remarkable achievement since it
has become clear that non-human primates do not actually
have a physically structured vocal tract which is suitable for
articulating the sounds used in speech. Apes and gorillas can,
like chimpanzees, communicate with a wide range of vocal
calls, but they just can’t make human speech sounds.
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