Koko The Famous Sign Language "Talking" Gorilla Has Died

Penny was not just Koko's teacher, but mentor, mother, and friend.

Penny was not just Koko's teacher, but mentor, mother, and friend. The Gorilla Foundation

Koko the gorilla, famous for learning how to speak using sign language with her human trainer, has died at the age of 46.

“Koko touched the lives of millions as an ambassador for all gorillas and an icon for interspecies communication and empathy,” The Gorilla Foundation said in an announcement of her death, which occurred last night in her sleep. “She was beloved and will be deeply missed.”


At the height of her fame, Koko was (twice) a cover girl for National Geographic, met celebrities such as Robin Williams, and rocked the scientific establishment with her seemingly extraordinary abilities. Not without controversy, the gorilla was known worldwide as the ape that could “talk”, and became a prominent icon for the conservation of her species, and wildlife as a whole.

The incredible tale of Koko, and how she rose to such global prominence, began back in 1971 when a female gorilla in San Francisco Zoo rejected her infant. This gave Stanford University graduate Penny Patterson a unique opportunity to see if her extraordinary – and somewhat unconventional – idea of teaching a great ape how to talk, was in any way possible.

Over the next few years, Patterson worked with the young gorilla eventually founding Project Koko, and claimed that Koko could understand and use over 1,000 different words in American Sign Language. For the next four decades, Patterson not only looked after and taught Koko, but effectively became her mother, friend, and interpreter.

Through this intimate relationship, Patterson claimed that Koko could talk about the future, rhyme, tell jokes, and even lie. Yet despite Patterson’s assurances about what Koko could do, the scientific community has remained steadfastly critical of these assertions. This is mainly down to the fact that due to her close relationship with Koko, Patterson was understandably very defensive of her, and refused to allow independent researchers access.


Despite this controversy, Koko was still able to capture the curiosity of the world. One of the most important things to have arisen out of Project Koko is the realization that animals – and great apes in particular – are intelligent, sentient, and emotional individuals. Nowhere is this demonstrated more than through Koko’s fondness for keeping "pet" kittens, one known as All Ball in particular.

With her death we lose a genuine icon of the natural world, but she will not be easily forgotten. Challenging the status quo and how we see ourselves, her legacy is one that altered the landscape of conservation, psychology, and zoology, and is set to continue long into the future.  

“The foundation will continue to honor Koko’s legacy and advance our mission with ongoing projects including conservation efforts in Africa, the great ape sanctuary on Maui, and a sign language application featuring Koko for the benefit of both gorillas and children,” said The Gorilla Foundation.


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