Koko.Org / The Gorilla Foundation

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The primary program of The Gorilla Foundation/Koko.org involves teaching American Sign Language to two lowland gorillas, Koko and Michael (who recently passed away). The Gorilla Language Project, or Project Koko, is the longest continuous inter-species communications project of its kind in the world, and it serves as a unique and irreplaceable resource for the international conservation community.

Studying gorilla intelligence and behavior will lead to a greater understanding of the species' physical and psychological needs. Only through knowledge can humans take the necessary steps to improve the treatment of captive gorillas and protect free-living gorillas from extinction.

Koko, a female lowland gorilla born in 1971, and Michael, a male lowland gorilla born in 1973, use sign language and understand spoken English. Koko's participation in this study began when she was one year old, and Michael's at the age of three and one-half. Their intellectual, physical, and linguistic development has been studied extensively since their infancy. Before Project Koko, very little was known about gorilla intelligence.

The Gorilla Language Project is both an effort to gather data about gorilla language and a case study of observed gorilla behavior and utterances. All signs, the context in which they occurred, the number of repetitions, and anything unusual that might have occurred during signing are recorded daily. The project administers informal and formal tests of vocabulary comprehension and of the understanding of relationships between objects and words, as well as standard child intelligence tests. There are also periodic video-taped sessions and audio-taped recordings.

During the course of the study, Koko has advanced further with language than any other non-human. Koko has a working vocabulary of over 1000 signs. Koko understands approximately 2,000 words of spoken English. Koko initiates the majority of conversations with her human companions and typically constructs statements averaging three to six words. Koko has a tested IQ of between 70 and 95 on a human scale, where 100 is considered "normal." Michael, the male silverback gorilla who grew up with Koko, had a working vocabulary of over 600 signs.

In addition to intensive studies of vocabulary acquisition, the project has investigated spontaneous gorilla language use. This involves the study of innovative linguistic strategies, invention of new signs and compound words, simultaneous signing, self-directed signing, displacement, prevarication, reference to time and emotional states, gestural modulation, metaphorical word use, humor, definition, argument, insult, threat, fantasy play, storytelling and moral judgment. The depth and variety of gorilla language use has significantly exceeded initial expectations. Indeed, evidence has been found for the existence, in less developed form, of almost every aspect of human behavior.

Project Koko is the cornerstone of TGF/Koko.org's work. By demonstrating the intelligence of gorillas, TGF/Koko.org can more effectively lobby for the humane treatment of captive animals and increased conservation efforts for those that are free-living. Project Koko has proven the stereotyped image of gorillas as blood-thirsty, destructive monsters unequivocally false. Indeed, it has forced a re-examination of traditional thought regarding all animals. The project has shown that an animal can possess qualities that were previously considered exclusively human, such as thought processes, imagination and feelings. This knowledge is crucial to all animal advocacy efforts, from the prevention of cruelty to animals to the conservation and preservation of endangered species.

The study of gorilla language acquisition sheds light on the vital connection between gorillas and their sibling species, homo sapiens. Project Koko has contributed to the study of the evolution and development of human communication and suggests a gestural origin of human language.