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

Koko, the western lowland gorilla who learned sign language and became a pop-culture phenomenon, died Thursday morning at the age of 46. The Gorilla Foundation, headed by Dr. Francine “Penny” ...

WOODSIDE, Calif. (CBS/AP)-- A beloved gorilla who rose to prominence by mastering sign language has died. Koko – a 46-year-old western lowland gorilla – died in her sleep at a preserve in California ...

Koko the gorilla who mastered sign language, raised kittens and once playfully tried on the glasses of the late actor Robin Williams, has died. She was 46.The Gorilla Foundation says the western ...

Koko the gorilla doted on her pet kitten as if it were her own child. To the amazement of her human handlers, she seemed able to capture the joys and annoyances of maternal love in strings of simple ...

Koko the gorilla, whose remarkable sign-language ability and motherly attachment to pet cats helped change the world’s views about the intelligence of animals and their capacity for empathy, has died ...

Koko the gorilla, whose remarkable sign-language ability and motherly attachment to pet cats helped change the world's views about the intelligence of animals and their capacity for empathy, has died ...

SAN FRANCISCO - Koko the gorilla, whose remarkable sign-language ability and motherly attachment to pet cats helped change the world's views about the intelligence of animals and their capacity for ...

WOODSIDE, Calif. (CBSNewYork/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 ...

Koko the gorilla, whose remarkable sign-language ability and motherly attachment to pet cats helped change the world’s views about the intelligence of animals and their capacity for empathy, has died ...

Koko the gorilla who mastered sign language, raised kittens and once playfully tried on the glasses of the late actor Robin Williams, has died. She was 46. The Gorilla Foundation says the western ...