Koko is perhaps the best known gorilla in the world because of her sign language and artistic abilities, her relationships with kittens, and a considerable amount of worldwide media since she was a baby. However, Koko is not the only gorilla that has mastered sign language (and art) — she has grown up with several equally interesting (and intelligent) friends. In this section, we introduce you to Koko and her extended family at The Gorilla Foundation, and contrast these “enculturated” gorillas with gorillas around the world.

Meet KoKo


When Penny Patterson, a young graduate student in psychology at Stanford, first saw a tiny, undernourished baby gorilla named Hanabi-Ko (which means “Fireworks Child” in Japanese) at the San Francisco Zoo, she had little inkling that the sickly ape would become her constant companion – and the subject of the longest continuous experiment ever undertaken to teach language to another species. But within a year, Project Koko was underway, and in two weeks the gorilla was using correct signed gestures for food, drink, and more. Today, four decades later, Koko has a vocabulary of more than 1,000 words.

Born on July 4th, 1971, Koko had a difficult life as a infant, became seriously ill, and had to be hand-reared by a caregiver, and later Penny, when she was rejected by our gorilla mother.  Penny agreed to take care of Koko for at least a few years, and was allowed to teach her sign language as the focus of her PhD dissertation in developmental psychology at Stanford University.  But Penny didn’t expect to develop such a strong emotional bond with Koko — nor that Koko was going to teach her so much about love.  And so, what started out as 4-year commitment became a 4-decade (lifelong) relationship that changed the world — from viewing gorillas as huge, scary monsters (ala “King Kong”) to sensitive, empathetic beings much like us (think “Koko’s Kitten”).

Koko passed away on June 18, 2018, of natural causes, and the world will never be quite the same.  Nevertheless, Koko’s Legacy lives on, with the help of The Gorilla Foundation, as it turns out that “all gorillas are Kokos” — and can benefit greatly from what we’ve learned from Koko.

Meet MichAEl


Michael came to The Gorilla Foundation from Vienna in 1976 at the age of 3, having been born in Cameroon, Africa. Although originally intended as Koko’s mate, it eventually became apparent that he and Koko had developed a sibling relationship instead. Always bright and curious, Michael learned over 20 signs during his first year with The Gorilla Foundation and developed a vocabulary of more than 600 signs by the time he reached adulthood. He was the only “talking” gorilla in the world besides Koko, his female counterpart. Unfortunately, Michael passed away suddenly on April 19, 2000. See Michael’s Memorial for details. Michael was a “great ape” in every sense, and he has left a legacy that will live on indefinitely. We at The Gorilla Foundation miss him dearly.


Meet Ndume


Ndume joined the Gorilla Foundation/Koko.org in 1991, after spending his first 10 years at the Cincinnati Zoo, and .  Born in 1981 and already a father of three by the age of 10, the 400-pound Ndume was Koko’s intended mate. Ndume has also provided the opportunity for us to discover methods of dealing with aberrant behaviors. This information will benefit all captive gorillas.

Koko selected Ndume from a number of available males (via a process akin to “video dating”— see intro video below) and though they became good friends,  they did not become mates. The suspected  reason for this is that Koko was never given the opportunity (by the zoo community) to have a natural gorilla family group — with multiple females and one male. This female support system is important because of how much bigger and stronger gorilla males are than females.

After Koko passed away (in June of 2018), The Cincinnati Zoo (CZ) requested that Ndume be transferred “back” to The Cincinnati Zoo (after 27 years of life at the Gorilla Foundation’s private sanctuary).  Because of an ownership agreement, The Gorilla Foundation had no choice but to comply (after contesting the risky move for almost a year in the courts).  While the zoo had a valid point that Ndume could benefit from being around other gorillas, TGF felt it would be better to provide such gorilla companionship to Ndume at the Foundation, so that he could keep his life-long human companions a well.  At the time of this writing, Ndume had just arrived at CZ, along with two of his favorite TGF caregivers, who will be spending up to 2 months with him to support his adaption, which we hope proceeds smoothly.  Stay tuned for updates …