In Loving Memory of Koko

Koko, a western lowland gorilla who captivated the world by learning to communicate through modified American Sign Language, died peacefully in her sleep on June 19, 2018, at the Gorilla Foundation in Woodside, California. She was forty-six years old. Born Hanabi-Ko (Japanese for "Fireworks Child") on July 4, 1971, at the San Francisco Zoo, Koko began her language training at the age of one under the guidance of animal psychologist Dr. Francine "Penny" Patterson. Over the course of her life, Koko reportedly mastered over one thousand signs and demonstrated comprehension of approximately two thousand words of spoken English. Koko's significance transcended vocabulary counts. She displayed what many interpreted as emotional depth: grief when told of the death of her beloved kitten, All Ball, who was struck by a car in 1984; playfulness when meeting actor Robin Williams; and what appeared to be self-awareness, responding to her own reflection and expressing preferences for colors, foods, and companions. Her critics argued that much of her communication was prompted or over-interpreted by handlers. The scientific debate over whether Koko truly possessed language was never fully resolved. But even skeptics acknowledged that she demonstrated something remarkable: a bridge, however imperfect, between two species that share ninety-seven percent of their DNA. Koko spent her final years at the Gorilla Foundation's sanctuary, surrounded by caregivers and her longtime gorilla companion, Ndume. She enjoyed painting, playing with kittens, and watching nature documentaries. Whether Koko truly understood language in the way humans do may be beside the point. She made millions of people pause and wonder whether the boundary between human and animal minds is as firm as we have always assumed. That question is her legacy.