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Koko the gorilla used smarts, empathy to help change views


Fans mourned Koko's passing, and the foundation's website experienced excessive traffic on Thursday.

SAN FRANCISCO (AP) — Koko the gorilla, whose remarkable sign-language ability and motherly attachment to pet cats helped change the world's views about the intelligence of animals and their capacity for empathy, has died at 46.

Koko was taught sign language from an early age as a scientific test subject and eventually learned more than 1,000 words, a vocabulary similar to that of a human toddler.

She became a celebrity who played with the likes of William Shatner, Sting, Leonardo DiCaprio, Robin Williams and Mr. Rogers. At her home preserve, where she was treated like a queen, she ran around with Williams' eyeglasses and unzipped Rogers' famous cardigan sweater.

In so doing, Koko showed the American public that a giant ape didn't have to be scary but wanted to be tickled and hugged.

The Gorilla Foundation said the 280-pound (127-kilogram) western lowland gorilla died in her sleep at the foundation's preserve in California's Santa Cruz mountains Tuesday.

Koko was the not the first animal to learn sign language and communicate, but through books and media appearances she became the most famous. Yet there was debate in the scientific community about how deep and human-like her conversations were.

Koko appeared in many documentaries, including a 2015 PBS one, and twice in National Geographic. The gorilla's 1978 National Geographic cover featured a photo that the animal had taken of herself in a mirror.

"Koko the individual was supersmart, like all the apes, and also sensitive, something not everyone expected from a 'king kong' type animal that movies depict as dangerous and formidable," Emory University primate researcher Frans de Waal said in an email Thursday.

"It changed the image of apes, and gorillas in particular, for the better, such as through the children's book 'Koko's Kitten' that may young people have grown up with. To view apes as nice and caring was new to the public and a big improvement."

Koko watched movies and television, with her handlers saying her favorite book was "The Three Little Kittens," her favorite movies included the Eddie Murphy version of "Doctor Doolittle" and "Free Willy," and her favorite TV show was "Wild Kingdom."