LONDON, ENGLAND - MAY 02: Kumbuka, a 15-year-old western lowland gorilla, holds a green pepper as he explores his new enclosure in ZSL London Zoo on May 2, 2013 in London, England. The silverback male, who weights 185 kg and stands seven foot tall, moved from Paignton Zoo two weeks ago. It is hoped that Kumbuka will mate with the zoo's three female gorillas to increase numbers of the critically endangered species as part of the European breeding programme. (Photo by Oli Scarff/Getty Images)
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 its sleep at the foundation's preserve in California's Sana Cruz mountains on Tuesday.
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's capacity for language and empathy opened the minds and hearts of millions.
Koko appeared in many documentaries and twice in National Geographic. The gorilla's 1978 cover featured a photo that the animal had taken of itself in a mirror.
The foundation says it will honor Koko's legacy with a sign language application featuring Koko for the benefit of gorillas and children, as well as other projects.