You may have heard of Koko – the west lowland gorilla who has been taught to “speak” to humans, using American Sign Language (ASL). Koko started learning sign language in 1972, at the age of one. Now 44 years old, Koko knows around 2000 words, ranging from basic objects to emotions. Project Koko, led by Dr Penny Patterson, is the longest uninterrupted study on ape language abilities. It was started to find out not only about gorillas and their cognitive abilities, but also to investigate what makes language human.
Koko has caught the eye and, in some cases, heart of many celebrities. Her friends include Betty White, Leo Di Caprio, Sting, Peter Gabriel, William Shatner, Mister Rogers and more. She established an especially close bond with late comedian Robin Williams. By the end of their first meeting, Robin and Koko were tickling each other and playing chase.
Many parallels have been found in the way Koko learns sign language with the way a small child learns sign language. However, Koko learns significantly slower and asks fewer questions. As Koko has an IQ which would not suggest she would learn slower, it is believed this may not be because gorillas are less capable of learning sign language, but rather because Koko is obviously not immersed in the same social situations as a human child.
As Dr Patterson teaches Koko the sign language, she also speaks the words aloud. This has allowed Koko to comprehend a lot of spoken English, which often shocks people the first time they meet her. They expect to be able to make comments about Koko to her trainers and are surprised to find that she follows the conversation.
Although Koko’s trainers are convinced she truly understands the words she is using, there are critics who argue that she is just mimicking, as Koko receives a reward when she signs certain words. Many claim that a lot of the data collected from Koko may be due to the Clever Hans effect – when asked a question, Koko may not be understanding and responding to the question, but rather can tell from her trainer that she is supposed to sign “yes”.
In response to these criticisms, Koko’s trainers argue that she is capable of sophisticated sign language, with consistent grammatical structure. Furthermore, Koko has been known to invent new signs for words she has not yet learned by stringing together words she knows, such as “scratch comb” instead of brush.
One aspect of Koko’s personality which has captured many people’s hearts is her love of kittens. For years, Koko tried telling her trainers that she wanted a baby, and used to cuddle toy dolls. Obviously baby gorillas are not easy to come by, so instead the researchers got her kittens. Koko can be seen cuddling her kittens, and consistently asks for them to be put on her head.
It appears that Koko is capable of expressing complex emotions. When Koko’s first kitten, All Ball, was tragically killed by a car, Dr Patterson told Koko. Koko responded by saying she was sad, and her trainers report that she grieved for days afterwards.
Koko communicates feelings in a way that suggests extraordinary emotional depth. She has shown empathy, not only for other gorillas but also for humans. This has philosophical implications, as many would have once said that what makes humans human is that we have complex language and a sense of empathy, but it appears we actually share both of these traits with other primates.
There was a hope that Koko would show the world that gorillas are worth protecting – if they are capable of showing empathy towards us, shouldn’t we in return stop poaching them, and destroying their habitat? However, in the last 20 to 25 years (over 20 years into Project Koko), West lowland gorilla populations have fallen by 60%, largely due to poaching for bush meat.
Koko currently lives at The Gorilla Foundation in California, and was recently given a box of kittens to chose from as a 44th birthday present. She continues to use sign language every day, and has recently started to learn to read. In the future, Dr Patterson hopes that, some day, Koko may have a baby. If she does, the world will be watching to see if Koko can teach her infant sign language.