Taboos in Chimp Communication

Humans are not the only primates that use taboo language. In Project Washoe, which aimed to teach chimpanzees sign language, the chimps internalized certain taboos, including one around the toilet. The sign for "dirty" was used to represent something shameful, and the chimps eventually began using that sign as an admonition or to express anger, much like a curse word, demonstrating the existence of a form of stigma within their social behavior.