Efforts to teach non-human primates to communicate with humans
Facial expressions can be used to convey a message.
Research into great ape language has involved teaching chimpanzees , bonobos , gorillas and orangutans to communicate with humans and each other using sign language , physical tokens, lexigrams , and imitative human speech . Some primatologists argue that the use of these communication methods indicate primate "language " ability, though this depends on one's definition of language. The cognitive tradeoff hypothesis suggests that human language skills evolved at the expense of the short-term and working memory capabilities observed in other hominids .
By that extension, contemporary animal cognition research leans toward not teaching apes human forms of communication, but rather observing apes in their inter-species communication.[1] [2] [3] [4] Additionally, earlier distinguished case studies in the research field such as Nim Chimpsky , and Koko have been criticized as having subjects produce results based on operant conditioning .[5] [6] [7]
However, there is still evidence of certain apes, such as Kanzi the Bonobo , understanding crucial aspects of human language such as grammar, extensive vocabulary and reversible sentences.[8]
^ Amici, Federica; Liebal, Katja (1 April 2023). "Testing Hypotheses for the Emergence of Gestural Communication in Great and Small Apes (Pan troglodytes, Pongo abelii, Symphalangus syndactylus)" . International Journal of Primatology . 44 (2): 319–340. doi :10.1007/s10764-022-00342-7 . ISSN 1573-8604 .
^ Amici, Federica; Liebal, Katja (26 September 2022). "The social dynamics of complex gestural communication in great and lesser apes ( Pan troglodytes , Pongo abelii, Symphalangus syndactylus )" . Philosophical Transactions of the Royal Society B: Biological Sciences . 377 (1860). doi :10.1098/rstb.2021.0299 . ISSN 0962-8436 . PMC 9358312 . PMID 35934967 .
^ Fröhlich, Marlen; Wittig, Roman M.; Pika, Simone (1 May 2016). "Should I stay or should I go? Initiation of joint travel in mother–infant dyads of two chimpanzee communities in the wild" . Animal Cognition . 19 (3): 483–500. doi :10.1007/s10071-015-0948-z . ISSN 1435-9456 . PMC 4824811 . PMID 26833496 .
^ Hobaiter, Catherine; Byrne, Richard W. (1 September 2011). "The gestural repertoire of the wild chimpanzee" . Animal Cognition . 14 (5): 745–767. doi :10.1007/s10071-011-0409-2 . hdl :10023/4445 . ISSN 1435-9456 . PMID 21533821 . S2CID 13793972 .
^ Petitto, Laura A.; Seidenberg, Mark S. (1 September 1979). "On the evidence for linguistic abilities in signing apes" . Brain and Language . 8 (2): 162–183. doi :10.1016/0093-934X(79)90047-6 . ISSN 0093-934X . PMID 487067 . S2CID 39620186 .
^ Pepperberg, Irene M. (1 February 2017). "Animal language studies: What happened?" . Psychonomic Bulletin & Review . 24 (1): 181–185. doi :10.3758/s13423-016-1101-y . ISSN 1531-5320 . PMID 27368639 .
^ Neisser, Arden (1990). The Other Side of Silence: Sign Language and the Deaf Community in America . Gallaudet University Press. ISBN 9780930323646 .
^ Schoenemann, P. Thomas (21 July 2022). "Evidence of Grammatical Knowledge in Apes: An Analysis of Kanzi's Performance on Reversible Sentences" . Frontiers in Psychology . 13 . doi :10.3389/fpsyg.2022.885605 . ISSN 1664-1078 . PMC 9355523 . PMID 35936253 .