Thursday, October 23, 2008

A chimp Newton?

kw: book reviews, nonfiction, chimpanzees, language

Nim Chimpsky: The Chimp Who Would be Human, by Elizabeth Hess, chronicles the life of the most remarkable of the "signing chimps", the ones who were taught to communicate using American Sign Language, or ASL. I was quite excited to see this book. I've read for years about the experiences of Washoe, the first chimp taught a lot of ASL by Roger Fouts and his family and friends. And I've read about Koko the signing gorilla, taught mainly by Penny Patterson, whose repertory (vocabulary?) totals more than 1,000 signs.

Nim was raised as nearly like a human as possible, by two families. He was, as his name indicates, intended to disprove the language theories of Noam Chomsky, who considers humans unique bearers of "true language." Eight years since Nim's death, the question is not settled, but I see it as a matter of definition…just how "true" do you mean?

Chimps grow up about five times as fast as human infants, at first, reaching adolescence about age six, then slowing down so that the females give birth beginning about age 12. The trouble is, a two-year-old chimp is not that much like a four-year-old human. A male in particular is, at 30-40 pounds, already stronger than almost any human male, and chimps are always much, much more excitable than humans. A childish tantrum in the home can result in the need to replace all the furniture.

In his first three years, the stresses of raising Nim broke up two marriages. Chimpanzee mothers remain in constant, 24/7 contact with their young for four years. Human mothers can't meet the expectations of chimp babies. Nim's fourth year was spent in a cage. He was already too strong, too aggressive, and too dangerous to be fully integrated into any human family. "You can take the ape out of the jungle, but you can't take the jungle out of the ape."

All together, about 25 people taught ASL to Nim. This chart shows his progress up to the age of four (Click for a larger, more readable chart, scanned from p166). His final repertory was about 150 signs, but he was much more fluent than other signing chimps, and much more at ease communicating with humans. Most signing chimps will sign back if someone makes ASL signs to them. Only Nim typically initiated communication.

This may have something to do with the more intensely "family" atmosphere that his first sponsor, Herbert Terrace, set up with the families that raised Nim. But I think it is also that Nim was an extraordinary chimpanzee. One of his nicknames was Houdini, for his persistent facility in breaking out of any kind of enclosure. All chimps try to figure out any kind of lock on their cage; Nim excelled above all in his success at escaping. Nim may not be an apish Newton, but he might be compared with David Copperfield! Yet, in the end, Dr. Terrace was not sure his communication could be called language.

This is worth a bit of philosophical thought: human tools, including language, suit human needs, and evolved with the species, beginning at least 100,000 years ago, and perhaps much, much earlier. In the past six million years or so, hominids evolved into humans, and pongids evolved into chimpanzees. The kinds of communication chimps employ suit their needs in their environment. The onus is on us to understand chimp "language", and so far we aren't doing that very well. The most complex animal "language" yet decoded is the dances of bees, used to tell other bees where to find food or the next nesting hole.

It is not a matter of brain size. African gray parrots can learn human spoken language, and they seem to understand what they are saying, to the point of making basic conversation. All this with a brain a tenth the size of a chimp brain. Koko, supposedly a smaller-brained ape (relative to body size), has seven times the repertory and even more fluency than Nim. Yet the experts continue to claim the matter is not settled.

I find it a bit arrogant for Chomsky to claim that human grammar is the only grammar there is. Deaf people who communicated with Nim might report a long sentence he made, when the others present who knew ASL would have seen only two or three signs. Prior to 20-30 years ago, ASL was uninflected. A movement to make ASL an "institutional" or "correct" language added signs to distinguish "have gone", "going", and "went" from "go", for example. So during the 1970s—Nim's heyday—a deaf person might intend to say, "I am going to the store to get eggs and milk", and use the signs GO STORE EGGS MILK. Sign language interpreters (including a couple we know well) routinely expanded such an utterance into a complete English sentence. Nim's signing YOGURT NIM EAT was perfectly grammatical to a "native" ASL signing deaf person of the time. Thus, the statement of one deaf woman upon meeting Koko: "I just spoke with a nonhuman in my native language."

Nim lived in a primarily caged environment from age four to age 24, when he died of a heart attack. The book doesn't say, but I suspect a combination of human foods and extreme stress weakened his heart. Nim never saw another chimpanzee until he was four. As one of his handlers noted, he was probably expecting to lose his hair and grow up into a human some day. He also spent periods of a year or two at a time in isolation, which is very, very hard on any chimp, but was doubly hard on Nim.

The author unblinkingly chronicles the casual cruelties of some of the keepers. Not those who cared for Nim directly, but the head of the Norman, OK facility where he was born and spent part of his adolescence, the owners of the medical facility he got briefly sent to, and two early farm managers at Black Beauty Ranch, where he spent the last 18 years of his life. Fortunately, a third manager brought in made things much better for Nim as an adult.

This is the dark side of all these studies. You have to distort the animal to learn anything about such things. I continue to support the work of those like Jane Goodall, those who study the chimps in their own place and on their own terms. I suspect Ms Goodall speaks Chimp better than even she realizes. We'll never get these animals to discuss the daily news with us; it is pretty much irrelevant to them. But I suspect they'd have a lot to say about the 150 different kinds of food they eat, the many kinds of trees that are better or worse for making their nests, and the sundry attractions of the opposite sex. We just have to learn their words.

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