Koko, the gorilla who could use sign language, has passed away at 46 years old. Koko ‘The Sign Language Gorilla’ Passes Away Aged 46 By : Emily Brown 12.5k Shares Koko The Sign Language Gorilla Passes Away Aged 46 kokoGorilla Foundation/Twitter Koko, the gorilla who could use sign language, has passed away at 46 years old. Koko became famous worldwide in the 80’s when she suc