Probably in the wild life, they would never have created a significant gestural system. However, with the ASL system, they show many human skills for the learning and use of it. Of course, the language that the apes use is
Product of human intervention and teaching. The experiments that were mentioned do not suggest that the apes can invent a language (human children have not faced this task alone either). However, young amas learned the fundamentals of gestural language and showed that they can use it productively and creatively, although not with the sophistication of humans who use said language. The apes, like humans, also try to teach their language to others. Lucy, without fully realizing the difference between the hands of primates and feline claws, once tried that her mascot cat expressed himself with her claws in the ASL language. Koko taught Gestures to Michael, a male gorilla, six years younger than her. The apes also showed linguistic displacement. Absent in calling systems, that is a key ingredient of language. Usually, each call is linked to an environmental stimulus such as food. The calls are issued only when said stimulus is present. Displacement means that humans can talk about things that are not present. Humans do not have to see the objects to say the words. Human conversations are not limited by place and space. And we can distinguish the past and the future, share experiences with others and benefit from theirs. Patterson described several examples of Koko’s displacement capacity (Patterson, 1978). The gorilla once expressed sadness for having bitten Penny three days before. Koko used the “Later” sign to postpone the things she did not want to do. The recapitulation table 5.1 summarizes the contrasts between language, either signs or spoken, and call systems that primates use primates in wildlife. Some academics doubt the linguistic capabilities of Chimpanzees and Gorillas (Sebeok and Umiker-Sebeok, EDS., 1980, Terrace, 1979); They claim that Koko and chimpanzees are comparable to circus animals trained and really
Kanzi, a male bonobo, identifies an object that he has just heard through hearing aids. At an early age, Kanzi learned to understand simple human speech and communicate with the use of lexigrams, abstract symbols representing objects and actions. In the background a lexigram keyboard is observed.