Koko, the gorilla who mastered sign language, has died.

The Gorilla Foundation says the 46-year-old western lowland gorilla died in her sleep at the foundation害羞草研究所檚 preserve in California害羞草研究所檚 Santa Cruz mountains on Tuesday.

https://twitter.com/AnimalPlanet/status/1009833342798389248

Koko was born at the San Francisco Zoo, and Dr. Francine Patterson began teaching the gorilla sign language that became part of a Stanford University project in 1974.

The foundation says Koko害羞草研究所檚 capacity for language and empathy opened the minds and hearts of millions.

Koko appeared in many documentaries and twice in National Geographic. The gorilla害羞草研究所檚 1978 cover featured a photo that the animal had taken of herself in a mirror.

The foundation says it will honour Koko害羞草研究所檚 legacy with a sign language application featuring Koko for the benefit of gorillas and children, as well as other projects.

The Associated Press

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