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Ron Cohn/Courtesy of the Gorilla Foundation/

One area outshines all others in provoking crazy talk about language in the media, and that is the idea of language acquisition in nonhuman species.

On June 19 came the sad news of the death of Koko, the western lowland gorilla cared for by Francine “Penny” Patterson at a sanctuary in the Santa Cruz Mountains. Many obituaries appeared, and the press indulged as never before in sentimental nonsense about talking with the animals. Credulous repetition of Koko’s mythical prowess in sign language was everywhere.

Jeffrey Kluger’s essay in Time was unusually extreme in its blend of emotion, illogicality, wishful thinking, and outright falsehood.

Koko, he tells us, once made a sequence of hand signs that Patterson interpreted as “you key there me cookie"; and Kluger calls it “impressive … for the clarity of its meaning.” Would you call it clear and meaningful if it were uttered by an adult human?


As always with the most salient cases of purported ape signing, Koko was flailing around producing signs at random in a purely situation-bound bid to obtain food from her trainer, who was in control of a locked treat cabinet. The fragmentary and anecdotal evidence about Koko’s much-prompted and much-rewarded sign usage was never sufficient to show that the gorilla even understood the meanings of individual signs — that key denotes a device intended to open locks, that the word cookie is not appropriately applied to muffins, and so on.

Above all, Koko never uttered sentences. Patterson saw the you key there me cookie sign sequence as intended to convey “Please use your key to open that cabinet and get out a cookie for me to eat"; but she would have been just as ready to accept “there cookie you me key” or “cookie there me key you” or any other random display of context-associated signs.

In English, none of the 120 orders in which we could arrange the words cookie, key, me, there, and you makes a grammatical sentence. (For one thing, we need a verb.) For Patterson, or for Kluger, any order Koko might have chosen provides evidence of linguistic command.

Much has been made of the story of Koko’s first pet kitten, which strayed onto a road and was killed by a passing car. Kluger reports that when told of the accident, Koko “expressed her grief in more or less the same way we would.”

Koko is said to have produced a sign sequence including “cat cry have sorry Koko love.” That’s not how I would express my feelings about my dead pet. (Your mileage may differ.) But doubtless any of the 720 possible orders of those six signs would have sufficed for Patterson (or Kluger) to interpret them as a eulogy.


If Koko had verifiably responded to the death report with an actual sign-language sentence meaning “Did the driver stop?” I might not be so dubious. But cat cry have sorry Koko love doesn’t appear to reflect even the vaguest understanding of what had happened.

You’ve seen expert users of American Sign Language (ASL) interpreting at theaters or on TV. Just watch video of a sign interpreter for a minute, and then view some of the available footage of Koko’s alleged signing. There is no resemblance at all.

But then Patterson does not claim that Koko learned ASL (though many newspapers wrongly assert that). She claims it was a different language, “Gorilla Sign Language.” The distinction is useful in rebutting any human signer who might claim to see no ASL in Koko’s gestural behavior.

Plenty of linguists have expertise in the analysis of sign languages, and none of them have ever independently confirmed Koko’s incipient linguistic competence. Koko never said anything: never made a definite truth claim, or expressed a specific opinion, or asked a clearly identifiable question. Producing occasional context-related signs, almost always in response to Patterson’s cues, after years of intensive reward-based training, is not language use. Not even if it involves gestures that a genuine signer could employ in language use.

Neither journalists nor laypeople will ever be convinced of that. Such is their yearning to believe that Koko had mastered language, and had things to say, and shared those things with Penny Patterson. They want to believe these things, and they will not be denied.


Moreover, they will accuse me (probably in the comments below) of being an arrogant, hyperskeptical, human-biased speciesist, contemptuous of ape abilities. But I would love to learn about the experiences and opinions of nonhuman primates through direct conversation with them. Unfortunately, all that was established by Penny Patterson’s years of devotion to training Koko was that we are not going to have that opportunity.