Koko the Gorilla died in her sleep, after having wowed the world with her sign language. (Photo: AFP Photo, The Gorilla Foundation)
One of the most famous gorillas in the world, known for being able to communicate via sign language, has passed away in her sleep on Thursday at the age of 46.
A western lowland gorilla, Koko was born in 1971 in San Francisco Zoo, and became famous after being trained to 'speak' using a modified version of sign language.
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The Gorilla Foundation was started to help promote the conservation of her species, and Koko spent the last of her days in the Santa Cruz Mountains where the foundation is based. She's been on the cover of National Geographic twice, and became even more loved after photos of her with kitten All Ball touched the hearts of the public. Since then she's raised many kittens.
Not only was her language skills impressive, Koko's ability to show empathy had made strides in scientists' understanding of gorilla's emotional capacity.
She's also had a lot of A-list stars as friends, including Mr Rogers, Robin Williams and Betty White, and loved to sign the word for 'love'.
"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," says the foundation in a statement.
"The foundation will continue to honour 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."
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