Systematic sampling was done of signing between five home-reared chimpanzees who had had 4-7 years of complete immersion in integrating their signing interaction into their nonverbal communication. Eight-eight percent of all signs reported fell into the social categories of reassurance, social interaction, and play. (SL)

Linguistics retains from its antecedents, philology and the study of sacred writings, some of their apologetic and theological bias. Thus it has not been able to face squarely the question how linguistic function may have evolved from animal communication. Chimpanzees' use of signs from American Sign Language forces re-examination of language…