Every year on July 4, Penny Patterson throws a birthday party near her Woodside, Calif., home. There are the usual markings of such an occasion — wrapped presents, a cake with candles, the singing of “Happy Birthday To You.” Except here, the annual guest of honor is a nearly 300-pound Western lowland gorilla named Koko.
Patterson, 69, first met Koko at the San Francisco Zoo in 1971, when she was a 24-year-old graduate student at Stanford University. The following year she began teaching sign language to the baby gorilla as part of her Ph.D. project, which made Koko famous around the world for her ability to “talk.” But over the course of 45 years, what started as a scientific experiment has evolved into an unconventional family arrangement in which love and commitment mix with controversy and regret.
Today, Patterson is still serving as the gorilla’s primary caregiver and their remarkable bond is the subject of the one-hour documentary “Koko: The Gorilla Who Talks,” premiering Aug. 3 at 8 p.m. on PBS.
“Right from the beginning Penny has given Koko birthday parties very similar to the birthdays you would give a child, and I think that reflects Koko and Penny’s relationship: that Koko is like a child to Penny,” says Bridget Appleby, a producer at BBC’s Natural History Unit.
Appleby was part of a three-person crew that spent a month in Woodside in June 2015 filming the gorilla and her adopted mother and combing the 2,000 hours of archival footage collected over 44 years of their sign-language experiment, known as Project Koko.
For the first two years of the study, Patterson tutored the gorilla at the San Francisco Zoo, then in 1974 she got permission to move Koko with her to Stanford. When the zoo demanded the five-year-old primate back for breeding two years later, Patterson, fearing Koko would be rejected by the other gorillas after being reared by humans, raised $12,500 to officially adopt her and agreed to find a male gorilla to mate with her.
Koko would go on to achieve global fame in the late 1970s and early ’80s, when National Geographic put her on its cover twice, including an image of her mourning the death of her pet kitten, which made headlines worldwide. She spawned the children’s book “Koko’s Kitten” and her own branded line of toys, and over the years she’s met celebrities such as William Shatner, Sting and Leonardo DiCaprio. She can even select her own films to watch. (“I understand her favorite movie is ‘Tea With Mussolini,’ ” Appleby says, referring to the 1999 drama starring Cher and Judi Dench as women who raise a young boy in 1930s fascist Italy.)
But not everyone was so impressed with the human-like Koko. As the documentary explains, after Patterson published her dissertation in 1979, behavioral scientists expressed skepticism of her language claims (Koko is now said to understand 2,000 words of spoken English and knows 1,000 signs). The most vocal critic was Herb Terrace, founder of the chimpanzee language experiment Project Nim, who published his doubts — claiming Koko was just mimicking her handler — in a 1982 paper in the New York Academy of Sciences titled “Why Koko Can’t Talk.”
Such naysayers made it harder for ape language studies to get funding, forcing researchers to abandon their animal subjects or be shunned by the scientific community, as the documentary notes. Patterson fell into the latter group, and decamped Stanford for Woodside in 1979, where Koko has lived in a wooded sanctuary located a 20-minute drive from her home ever since.
Nearly 40 years later, Patterson’s life still exclusively revolves around gorillas. As Appleby observed, her day starts around 11 a.m. and she spends the late morning and early afternoon doing managerial work for The Gorilla Foundation, the organization that supports Koko — taking phone calls, doing interviews and making staff schedules.
Five days a week around 3 p.m., Patterson drives to the 7-acre sanctuary where Koko and a male gorilla named Ndume live. A team of eight caregivers are available to sit with Koko whenever she’s awake, as well as Ron Cohn, Patterson’s 73-year-old Stanford classmate who has filmed the signing project from the beginning and who has a house on the compound.
There, Patterson does signing and other enrichment activities with the gorillas, feeds and sees them to sleep. She often stays at the on-site research facility until 1 or 2 a.m. preparing their food for the next day — a diet that includes raw vegetables, soups, smoothies, juices and sometimes even human food such as pizza.
“I didn’t see Penny with very much ‘me’ time,” Appleby says. “It felt like her entire conscious, living, waking time was all focused around Koko, which you seldom see apart from a parent-child relationship.”
Patterson had the maternal instinct from a young age. She grew up in Illinois and Minnesota the second eldest of seven siblings, whom she helped raise after her mother died of cancer when she was a teen. But her absolute devotion to Koko has affected her relationship with her family as an adult.
One brother, Chris, lived in the Bay Area for years, so he was familiar with his sister’s unusual living situation; her other five siblings are less involved and have accepted her absence at family functions.
Patterson never married and while she once considered having children, as she says in the documentary, “I don’t think I was made for it. I think I was made for what I’m doing.”
As Appleby puts it, “From what we’ve seen, Koko is the love of her life — although obviously Ron has been a huge fixture in her life and a big mainstay in terms of partnering. The way they talk about it is Ron’s Koko’s father, Penny’s Koko’s mother; they [are] a cross-species family.”
But a baby gorilla has remained elusive. The first male companion, Michael, joined Koko in 1976, but she treated him like a brother (he died in 2000), and mating attempts with Ndume, who joined the group in 1991, have also been unsuccessful.
While Patterson expresses a feeling of privilege for her unique relationship with Koko, the topic of not being able to see her “daughter” become a mother is an emotional one, and she tears up when speaking about it in the documentary. Gorillas can live to their early 50s in captivity, and though Koko is technically still of reproductive age, time is running out.
“If [Penny] did the experiment again today … her effort to integrate Koko with other gorillas would have been [greater],” director Jonathan Taylor says. “She certainly regrets Koko not having a family and not being able to provide that for her.”
Today, the scientific community seems to agree Koko exhibits special skills — a 2015 study in the journal Animal Cognition found evidence of Koko performing learned human behavior not inherent to gorillas, such as coughing and mimicking phone conversations — but most remain skeptical of Patterson’s language claims, especially since she does not make her data available to outside researchers.
And yet criticism hasn’t slowed Patterson’s efforts as she nears 70 years old. While she is past normal retirement age, relaxation is not a part of her life, according to the filmmakers. She doesn’t go on vacation, her weekends are not spent socializing with friends.
“A big effect on her life is as long as Koko’s alive it will be absolutely devoted to looking after her,” Appleby says. “It’s not like having a child who leaves home at the age of 18. Koko won’t ever leave home. There is no end to that.
“It’s made her very single-minded.”
Koko turned 45 in July, and with both human and primate approaching their twilight years, the topic of what should happen in the case of death is a sensitive one for Patterson. While there are staff members who could physically look after Koko, as they did when Patterson was in the hospital for three weeks with a broken hip, the pair’s bond is irreplaceable — an effect the grad student likely never considered when first admiring that baby gorilla in the zoo decades ago.
“Penny began this when she was in her 20s. I don’t think she ever thought it would turn into this,” Taylor says. “You weren’t planning a 40-year experiment, you were planning a four-year experiment and then like a lot of things in life, it takes on a momentum of its own.”
