Tuesday, October 21, 2008

Chimp language?

kw: musings, animals, language, chimpanzees

I am halfway through a biography of Nim Chimpsky, the chimp whose language facility was supposed to disprove Noam Chomsky's theories of the human "grammar engine". On the surface, his theory seems nonsensical to me, because it posits the sudden development of a major mental ability that seems to have no precursor in the evolutionary past. It is the intellectual equivalent of a brief mutation sequence producing a new kind of limb upon the body, making us perhaps pentapods or hexapods (we are tetrapods).

The animal named Nim was the subject of H.S. Terrace's work. Two families raised him from an infant and they and others laboriously taught him ASL signs. Nim did learn to communicate using ASL, but there is little evidence that he said things using ASL that an unschooled Chimp could not communicate via other means. In 1979 H.S. Terrace wrote, "I could find no evidence of an ape’s grammatical competence, either in my data or those of others." (H. S. Terrace, “How Nim Chimpsky Changed My Mind,” Psychology Today, November 1979, Vol. 13, No. 6, p. 67)

Looked at in a larger context, researchers into whale and dolphin communication recognize that there must be some kind of grammar involved, but it is too different from our own and we can't figure it out. In the same way, all primates use a combination of sounds, postures and gestures to communicate according to their own social needs. What we find in the case of the numerous Chimps and a Gorilla or two that have been taught ASL signs, is that they seem to learn a vocabulary of signs equivalent to their "natural" vocabulary. It would be instructive to compare lists made by researchers in the animals' native habitats, of their "natural vocabulary" (as well as a human could figure it out), with the repertory of signs of these trained animals.

The last common ancestor between Human and Chimp lines was six or seven million years ago. Not only has the genus Homo developed and finally become "sapiens" since then, a similar level of change has occurred in the Chimp lineage, to produce Pan troglodytes and the Bonobo. They are as different from that common ancestor as we are. There is some kind of "grammar engine" in the brains of many mammals and birds. Our relatively gigantic brain simply has the extra power to support a much more intricate grammar, so I conclude that Dr. Terrace is only partially right. He sees no evidence of Grammar...at the Human level. But I see evidence of a Chimp-level grammar.

None of these primates has been trained much beyond the age of about four. By that age, they are, at 40 to 50 pounds, too large, aggressive and dangerous for intimate human contact. Did you know that nearly all the "media Chimps" are female? It is because they are less likely to suddenly kill their handlers, than are males. In Chimp society, all males are in a constant battle for status, and their "skirmishes" are at a level humans find lethal. The rare human who has achieved Alpha status with adult male chimps has to maintain it with the use of cattle prods and 2x4's. What is seen by some as cruelty and abuse is probably considered "barely adequate" social control by the Chimps.

It is sad that Nim and other "ASL-speaking" chimps had to spend all their life after the age of four in caged or zoo conditions. But there's no other way to keep the rest of the human world around them safe from them, or them safe from gun-toting vigilantes should they attempt free life "outside". All the better reason to leave them in the jungle where they know how to live, and to keep people (other than a tiny handful of researchers) strictly OUT.

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