"The Gorilla Foundation is sad to announce the passing of our beloved Koko," the research center says, informing the world about the death of a gorilla who fascinated and elated millions of people with her facility for language.
Koko, who was 46, died in her sleep Tuesday morning, the Gorilla Foundation said. At birth, she was named Hanabi-ko — Japanese for "fireworks child," because she was born at the San Francisco Zoo on the Fourth of July in 1971. She was a western lowland gorilla.
"Her impact has been profound and what she has taught us about the emotional capacity of gorillas and their cognitive abilities will continue to shape the world," the Gorilla Foundation said.
Throughout her life, Koko's abilities made headlines. After she began communicating with humans through American Sign Language, she was featured by National Geographic — and she took her own picture (in a mirror) for the magazine's cover.
That cover came out in 1978, seven years after Koko was chosen as an infant to work on a language research project with the psychologist Francine "Penny" Patterson. In 1985, the magazine profiled the affectionate relationship between the gorilla and her kitten: Koko and All Ball.