Koko, the gorilla who mastered sign language and showed the world what great apes can do, has died. She died Tuesday in her sleep at age 46, The Gorilla Foundation said in a statement.

Koko, Gorilla Who Learned Sign Language, Dies At Age 46 June 21, 2018 / 9:49 AM EDT / CBS New York WOODSIDE, Calif. (CBSNewYork/AP) — Koko, the gorilla who mastered sign language, has died.

Koko, whose apparent aptitude for sign language endeared her to fans around the world, died in her sleep on Tuesday morning, June 19, 2018, according to the Gorilla Foundation, which oversaw her care.

WOODSIDE, Calif. (AP) — 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's preserve ...