The releases of the movies “Project Nim” and “Rise of the Planet of the Apes” have revitalized interest in chimpanzees’ acquisition of American Sign Language (ASL). While “Rise…” is a story of how ape intelligence leads to their freedom from medical experimentation, “Project Nim” documents a chimp’s very real downfall, facing a continuous pattern of broken social bonds that bottoms out in a medical research lab. While the tragic series of events in Nim’s life is factual, “Project Nim” does not give enough context to understand Nim’s real relevance to the sign language studies.
Although “Project Nim” leads the viewer to believe that Herbert Terrace came up with the idea of teaching sign language to a chimpanzee to test nature vs. nurture, the fact is that the project was just a poor replication. Psychologists R. Allen Gardner, Trixie Gardner and Roger Fouts had been teaching the signs of ASL to chimpanzees for over a decade before Terrace started teaching Nim. Terrace’s analyses failed to replicate because his method differed, leading to different results.
Although early on, Nim learned the signs of ASL in a relaxed, enriched home setting, Terrace collected his actual data in a small, windowless classroom where research assistants drilled Nim to name items correctly for a treat. “Project Nim” describes how the research assistants were frustrated by this environment as well as with Nim’s non-compliance, lack of interest, and lack of signing. Terrace concluded, not surprisingly, that Nim signed only to beg for items.
After Nim was moved back to Oklahoma, Chris O’Sullivan and Carey Yeager compared Nim’s productivity in the drill context with productivity in a relaxed conversational context, used by the Gardners and Fouts. The researchers found that Nim signed more, initiated more signing, and imitated less in the conversational context. Conversely, Nim became aggressive when they invoked Terrace’s drill method. This study and others that demonstrate the chimps’ abilities can be found in Teaching Sign Language to Chimpanzees.
As Fouts often says “Absence of evidence is not evidence of absence”. Terrace claimed that Nim was not using the signs of ASL in a communicative way, when in fact his data was based on methods not conducive to communication. Although Terrace’s project with Nim ended long ago, the chimps of the Gardners and Fouts continue to teach and amaze us at the Chimpanzee and Human Communication Institute. Perhaps they really can take over the world.