For the last four decades, Koko, the world’s most famous gorilla, has lived in a trailer in Silicon Valley, the subject of the longest-running project on ape sign language. With a reported vocabulary of hundreds of signs, Koko has appeared to express feelings almost anyone can relate to — a love of kittens, a desire to be a mother.
A new PBS documentary argues that Koko’s remarkable life “challenges what it is that makes humans unique.” The problem, though, is that the film never really makes clear what “it” is. Rather than diving into the question of ape language and dissecting Koko’s abilities, Koko — The Gorilla Who Talks focuses more on the relationship between Koko and researcher Penny Patterson.