The first animal to learn a human language has died. Washoe the chimp, who learned around 250 words in sign language, died at the age of 42 at Central Washington University. “Washoe was a treasured member of our family,” said Roger and Deborah Fouts, co-founders of the university’s Chimpanzee and Human Communication Institute (official statement).

AP, the Seattle Times and New York Times all note that some researchers have expressed scepticism over the degree of language chimps can acquire. “Language has to involve conversation. It can’t be as one-sided as it was with the chimps,” says Herbert Terrace, of Columbia University, in the Seattle Times. He apparently thinks signing chimps have just learned a more complicated way of begging for food.

Washoe’s adopted son Loulis was the first animal to acquire a human language from another animal. For more about Washoe, named for Washoe County, Nevada where she lived until age five, see Friends of Washoe. A memorial will be held on November 12.

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