Nim did in fact demonstrate some important aspects of language use. Despite his acquisition and use of numerous signs, Terrace decided that Nim was incapable of combining words to create novel ideas. The only occasions in which Nim produced combinations of signs were imitations of signs previously produced by his trainers. The CHCI at Central Washington University is home to a family of 5 chimps who, according to their trainers, have mastered the use of sign language and implement it in conversations with each other and their trainers. The chimps at CHCI use the signs alone and in combination with other signs.
Chimps generally utilize their signs in discussing aspects of family life.
The trainers have observed that young males frequently sign to talk about games, such as tickle and chase. An important finding about primate language use at the CHCI is that the chimps use signs to refer to natural language categories. This category generalization is similar to that of children as they first begin learning to speak. Chimpanzees have also shown that they are able to create novel signs by combining signs to convey a metaphorically different concept. The CHCI is considering a couple of possible continuations of their research, provided that funding is available.