Chimpanzees are capable of speech, according to a new analysis of decades-old images

In 1962, many American moviegoers were treated to an unusual display during screenings of the popular Universal News which aired before the feature film screenings. That year, a segment titled “Now Listen to This! Italians Unveil a Talking Chimp” aired, introducing audiences to Renata, a chimpanzee who was said to have been trained by her keeper to say “Mama.”

“As her foster mother explained, this is one of the most extraordinary chimpanzees in the world,” the famous voice of announcer Ed Herlihy can be heard in the decades-old footage. “You don’t need to know Italian to understand Renata’s accent when she gets the signal.”

Then, as Renata’s keeper taps her on the chin, the chimpanzee is shown saying the word “mama” several times.

The images, which were probably considered little more than a novelty at the time, represented something potentially extraordinary: evidence that a non-human primate displayed the ability to speak, albeit in a rudimentary way. Despite Renata’s unique talent, the images were largely forgotten and the prevailing view continued to insist that humans were the only primates with the neural circuitry necessary for speech.

However, Renata was not the only known example of a chimpanzee showing a limited ability to learn and pronounce human words. Decades later, in a video uploaded to YouTube on August 17, 2007, a chimpanzee named Johnny was also shown saying “mama,” apparently in response to requests from his owner, after which he received a treat.

Now, an international team of researchers who reviewed footage of Renata and Johnny has concluded that in at least three known cases, the chimpanzees were indeed able to learn human words while exhibiting limited speech capabilities.

“We recovered original footage of two acculturated chimpanzees pronouncing the word ‘mama’ and subjected the recordings to phonetic analysis,” write the authors of a new study published in Nature: Scientific Reports By Axel G. Ekström and colleagues. “Our analyses demonstrate that chimpanzees are capable of producing syllables, achieving phonetic contrasts between consonants and vowels by means of simultaneous recruitment and coupling of the voice, jaw, and lips.”

In their paper, the researchers say they conducted an online experiment in which participants were given recordings of the utterances to listen to, but were not told that they were listening to chimpanzees. Participants “reliably perceived the chimpanzee utterances as syllabic utterances, primarily as ‘ma-ma,’” the researchers write.

The researchers conclude that the vocal capabilities of great apes have been largely underestimated, writing that “chimpanzees possess the neural components necessary for speech.”

Great apes do not appear to show any signs of language use in the wild, and it is noteworthy that Renata and Johnny appear to have learned their unique talents through human training. Nevertheless, the findings are significant as they show that at least one species of non-human great ape possesses the neural components necessary to facilitate speech, regardless of whether or not they use such faculties on their own in the wild.

Although speech is not an ability that chimpanzees normally rely on, the same cannot be said for their general ability to communicate. Recent studies have shown that chimpanzees frequently use gestures to communicate in a manner similar to that of humans. In at least a few cases, chimpanzees have also demonstrated a remarkable ability to understand human language. One notable example is Kanzi, a bonobo who reportedly understands close to 3,000 human words and has demonstrated the ability to answer questions using a special keyboard that reproduces human words.

https://www.youtube.com/watch?v=ESKinbfgrkU

In their new paper, Ekström and colleagues note that previous studies of chimpanzees and their ability to express rudimentary language had largely been dismissed due to a lack of rigorous analysis. However, the new findings appear to support these previously unconfirmed observations, which often cited words like “mama” as one of those chimpanzees learn most frequently.

In fact, there might be something else to explain the prevalence of this particular word in previous studies of chimpanzee speech. As the study’s authors point out, “mama” is often among the first words human infants learn, and may in fact have deeper roots as one of the first words in spoken language ever created by humans.

“It has therefore been argued that ‘mama’ may have been one of the earliest words to appear in human speech,” the authors of the new study write.

“Our data complement this picture: chimpanzees can produce the so-called ‘first words’ of spoken languages.”

The team’s new study, “Chimpanzee utterances refute supposed missing links of novel vocalizations and syllabic speech,” was published in Nature: Scientific Reports July 25, 2024.

Micah Hanks is the editor-in-chief and co-founder of The Debrief. He can be reached by email at [email protected]He continues his work in es.micahhanks.com and in X: @MicahHanks.