Great Ape language

Research into great ape language has involved teaching chimpanzees, bonobos, gorillas, and orangutans to communicate with human beings and with each other using sign language, physical tokens, and lexigrams; see Yerkish. Some primatologists argue that these primates' use of the communication tools indicates their ability to use "language", although this is not consistent with some definitions of that term.

Animal language research attempts to answer the following questions:

Non-human animals have been recorded to have produced behaviors that are consistent with meanings accorded to human sentence productions. (A production is a stream of lexemes with semantic content. A language is grammar and a set of lexemes. A sentence, or statement, is a stream of lexemes that obeys a grammar, with a beginning and an end.) Some animals in the following species can be said to "understand" (receive), and some can "apply" (produce) consistent, appropriate, grammatical streams of communication. David Premack and Jacques Vauclair have cited language research for the following animals (but see "Criticisms of primate language research", below):

Sign language and computer keyboards are used in primate language research because non-human primate vocal cords cannot close fully, and they have less control of the tongue and lower jaw. However, primates do possess the manual dexterity required for keyboard operation.

Many researchers into animal language have presented the results of the studies described below as evidence of linguistic abilities in animals. Many of their conclusions have been disputed.

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