Koko the Gorilla Dead at 46

Koko the Gorilla

Dead at 46

6/21/2018 7:01 AM PDT

Koko, the famous gorilla who made several celebrity friends, died in a California preserve on Tuesday.

The Gorilla Foundation says she died in her sleep at the organization’s preserve in the Santa Cruz Mountains of Northern California.

Koko, a western lowland gorilla born at the San Francisco Zoo, gained fame in the ’70s and ’80s after Stanford University researchers taught her sign language. She mastered it, too … using 1,000 words to communicate with humans — and was able to understand 2,000 words of spoken English.

She was featured in National Geographic twice, and was the magazine’s cover girl in 1978. The cover shot was a selfie she took in a mirror.

Koko's Tribute to Robin Williams

Koko was tight with Robin Williams and Red Hot Chili Peppers bassist Flea.

Koko was 46.