For decades, the story of a western lowland gorilla named Koko excited and inspired people the world over. As they understood it, her apparent ability to learn sign language bridged the gap between humans and animals. It also didn't hurt that her signs demonstrated Koko's care and empathy for every living thing she encountered.
Koko's inspirational story and her abilities remained as popular as ever by the time she starred in a 2015 video that featured her final message to the world before her passing in 2018. But since then, experts have weighed in on what was really going on in that video.
How it all began
In 1971, a Stanford graduate student named Penny Patterson met the then-newborn Koko for the first time at the San Francisco Zoo.
According to PBS, Patterson had wanted to communicate with animals all her life and wondered if that could be achieved by teaching Koko sign language.
Not quite according to plan
As the BBC reported, Koko couldn't exactly learn American Sign Language the way humans do, but Patterson taught her a modified version that she called "Gorilla Sign Language" starting from when Koko was a year old.
In concert with a team of researchers, Patterson would work closely with Koko for the next 45 years and steadily build up her vocabulary over time.
A life spent in conversation
According to The Chicago Tribune, Patterson credited Koko with understanding about 2,000 words in Gorilla Sign Language by the time of her death at 46 years old.
And her linguistic capabilities were such that she could communicate using about 1,000 of them.
A controversial success story
But while Koko's apparent ability to express her thoughts and feelings through sign language impressed so many worldwide, other scientists have expressed doubt in the idea that this was genuinely what Koko was doing.
In their view, Koko's communication results from her handlers training her to make the responses they wanted to see rather than a genuine understanding of complex language.
Evidence for the skeptics
As chronicled by The Chicago Tribune, it wasn't unusual for Koko to make the wrong signs for terms she had learned until her trainers coached her to do otherwise.
Amusingly, she was apparently fond of the word "nipple" and had a habit of randomly signing it when left to her own devices.
How much did Koko really say?
Another common criticism of Patterson's methods concerned what critics described as anthropomorphizing her, meaning that her team saw human expressions and motivations in Koko's responses, whether it was accurate to do so or not.
As skeptics saw it, this was clear in the questions Koko's handlers often asked her, which they said were designed to make her simple responses seem more profound than they were.
Comparisons with other apes
Another issue was that Koko seemed to show greater care for matters of humanity and the world at large than other apes did when put under similar conditions.
For instance, Slate reported that a Bonobo named Kanzi, who was also taught sign language, only engaged in comparable commentary 4% of the time. The other 96% of his signs concerned immediate desires like food or specific toys.
A counter-argument from Patterson's team
To support the idea that Koko was genuinely signing her real feelings, The Chicago Tribune reported that Patterson's team showed Koko's eyes tearing up when she watched a sad movie.
They also released a video taken in the wake of Koko learning that her pet kitten, All Ball, had passed away after an encounter with a car. Koko signed "Bad, sad, bad" and "Frown, cry, frown" in response while engaging in the signed behavior.
The Robin Williams debate
This debate over the meaning of Koko's signs was particularly heated when it concerned her friendship with the late actor and comedian Robin Williams. They two got along famously and even tickled each other, which informed how Koko supposedly reacted to news of his passing.
But while The Chicago Tribune reported that she did sit solemnly in her enclosure that afternoon, it still remains unknown whether this reaction was due to grief at Williams' loss or simply Koko noticing how upset the news made her handlers.
The context of Koko's final message
Since the debate behind Koko's aptitude for sign language has never been resolved, it reignited in the wake of a video message she delivered in anticipation of the 2015 United Nations Climate Change Conference (COP21).
According to Snopes, the video was a collaboration between the Gorilla Foundation, which trained and cared for Koko, and a biodiversity organization called NOE Conservation.
A poetic introduction
Koko began her message by saying, "I am gorilla. I am flowers, animals. I am nature."
Since the video's description describes it as Noé letting nature have its say, this seems like a fitting introduction.
A loving gorilla
True to the gentle nature visitors felt when they met Koko, she then dedicated her next signs to declaring her love.
In her specific words, she signed, "Man Koko love. Earth Koko love."
Tough love
But in a moment that so many parents can relate to, Koko expressed how that love doesn't come without its share of frustrations and disappointments.
As she put it, "But man stupid. Stupid!"
Trying to compose herself
If this sounds harsh, it seems that it did to Koko as well. But as she expressed, she was simply overcome by emotion.
As she signed, "Koko sorry. Koko cry."
An urgent plea
Although Koko doesn't specify what she finds so stupid about humanity, her next words make it a little more clear as to what she's so frustrated about.
As she said, "Time hurry! Fix Earth! Help Earth!"
Something big was on her mind
Although Koko didn't mention concepts like climate change or biodiversity by name, her words show a sense of urgency that befits either of those aspects of the world's health.
So she reiterated, "Hurry! Protect Earth."
An ominous statement
While much of Koko's message seems urgent, it grows a little more mysterious and almost ominous as it winds down.
Once she calmed down a little, Koko signed, "Nature sees you."
Her last words
After she said her piece, Koko simply signed "thank you," presumably to the viewer for watching and listening to her.
The video then ended with Noé's call to include a measure for the preservation of biodiversity in the Paris Agreement that resulted from the COP21 talks.
A warm reception
The video has since attained over 2 million views, and the majority of the comments praise Koko's heart and intelligence.
Many also mourned Koko once news of her passing broke in 2018.
Supportive comments
One user reacted by saying, "I cried watching this. Koko, you speak my words too; you are so smart and beautiful."
In the words of another, "This message should be brought seriously. If Koko can witness a disturbance in [the] animal kingdom's peace, then it makes sense that we definitely need to hurry because time is running out."
Controversy reignited
According to Slate, one of the biggest criticisms that Herb Terrace — a psychology professor at Columbia University who conducted his own ape research with a chimpanzee named Nim Chimpsky — had of Patterson's work as far back as the 1980s was that he did not believe Koko's signs were spontaneous.
Instead, he argued, she was led to answer the way she did by Patterson and her team's questions.
A modern context for an old criticism
To skeptics, it seemed highly unlikely that the teams behind the video simply let Koko express herself unfiltered as they appeared to do at first glance.
When HuffPost asked Terrace whether it was possible for her to grasp concepts like climate change and biodiversity, he answered, "Of course not," and called the video "highly misleading."
Reading between the edits
As Terrace went on to say, "We don't know what Koko's trainer was signing to her before she uttered the various signs … attributed to her."
In a statement to NPR, linguistics professor Sherman Wilcox from the University of New Mexico said, "This is obviously a doctored video composed of highly edited clips of single signs pieced together to make it look like Koko is actually saying something when she's not.."
A partial admission from the Gorilla Foundation
In a release preserved by Snopes, the Gorilla Foundation said that Koko was presented with a script and that her message was edited from a number of separate takes.
They also admitted she had to be taught the words "nature" and "protect" for the video's purposes.
But only a partial admission
However, they also said that Koko was given room to improvise during their "brief daily video discussion sessions" and that they had briefed her on the topic of preserving biodiversity with a National Geographic issue titled "Cool It!"
They also described Koko as being genuinely interested in the topic.
An unamused response
In an article for NPR, biological anthropologist Barbara E. King argued that presenting Koko as almost human-like in her understanding of the world does more harm than good.
As she wrote, "It's not very respectful of the world's biodiversity to insist upon making apes into furry versions of ourselves."
Helping or hurting the fight against climate change?
Wilcox had similar reservations with the video, which he called "disconcerting on so many levels."
As he put it in an email to King, "I fear it diminishes the seriousness of the climate change issue. Climate change deniers already feel like scientists are lying to the public. We don't need to give them fake videos."
Sign language implications
Wilcox was also less than impressed by the way Koko's use of sign language supposedly mischaracterizes how it actually works.
As he wrote, "It feels disrespectful of ASL. Sign linguists have worked for more than six decades to show that signed languages have not only words but also syntax, the glue that enables us to use single words to express complex concepts."
Koko's use of syntax doesn't help her team's case
As Wilcox saw it, the video either gives the impression that American Sign Language lacks syntax or that Koko is incapable of understanding it.
In the latter case, he wrote, "Which may be true, but that denigrates the linguistic abilities that Koko apparently does possess."
Koko and ape language research
Finally, skeptics like Frans de Waal of Emory University's Living Links primate research center criticized the Gorilla Foundation's framing of Koko's aptitude for sign language as harmful to the field of ape language as a whole.
Speaking to HuffPost, he described the video as a "stunt" that has "given the ape-language field a bad name, whereas there is so much more to discover if we just study what cognitively advanced animals can do of their own accord."
