Hearing. Real name Hanabi-ko (Japanese for "fireworks child", from the date of her birth). The second great ape (or animal of any kind) to use American Sign Language, after the chimpanzee Washoe (q.v.). Born at the San Francisco Zoo; when a few months old, "adopted" by Dr. Penny Patterson for an experiment in teaching gorillas to use American Sign Language for communication with humans. Koko eventually learned between 600 and 1000 signs, and was the core of The Gorilla Foundation, a nonprofit organization for research in gorilla communication and preservation of the species. Koko also had her own pet cats. An intended mate, Michael (q.v.), was a dud (though he learned signs too), but in 1991 the Gorilla Foundation got another male gorilla, Ndume, for the hoped-for reproduction and experiment to see whether Koko would pass on sign language to her baby. As of mid-2000, however, Koko still had not become pregnant.
National Geographic, October 1978; http://www.gorilla.org (June 30, 2000).
4 July 1971-