Who Is Koko the Gorilla? Kitten Lover and Sign Language Expert Dies at 46

Koko the gorilla, one of the most researched and famous of the great apes, has died in her sleep at the age of 46. She was known for her incredible mastery of sign language, her love of kittens and for being the primary ambassador for her endangered species.

She was taught a version of American Sign language, and Koko became proficient enough with it that she can express thoughts and feelings to her instructors, especially to her life-long friend and caretaker, Dr. Francine Patterson, an animal psychologist who also extensively documented the gorilla's life.

"Koko touched the lives of millions as an ambassador for all gorillas and an icon for interspecies communication and empathy. She was beloved and will be deeply missed," the statement from the Gorilla Foundation said of her passing.

Her name Koko was derived from the name she was given at birth "Hanabi-ko," Japanese for "Fireworks Child," when she was born on July 4, 1971 at the San Francisco Zoo. A year after, she was placed under the care of Patterson, who taught her a modified version of sign language.

Koko, along with Patterson and Dr. Ronald Cohn, moved the project to Stanford in 1974 which became the start of the Gorilla Foundation. She was later joined by Ndume when the foundation transferred to the Santa Cruz Mountains as ambassadors of their species.

The gorilla went on to become the face of wildlife conservation, appearing on the cover of the National Geographic for her ability to "chat, tease, and even argue with scientists using sign language," as the magazine fondly remembered her on social media.

Koko, like most humans, also displayed an affection for cats, even using her mastery of sign language to give them names. She named her first kitten, a tailless tabby, as "All Ball." She also met Robin Williams in 2001, as the comedian made her give out her first smile in a while.