A team of scientists from Colorado State University, Save the Elephants and ElephantVoices used machine learning to confirm that calls of African savannah elephants (Loxodonta africana) contained a name-like component identifying the intended recipient. When the authors played back recorded calls, the elephants responded affirmatively to calls that were addressed to them by calling back or approaching the speaker.
Two juvenile elephants greet each other in Samburu National Reserve in Kenya. Image credit: George Wittemyer.
“Dolphins and parrots call one another by ‘name’ by imitating the signature call of the addressee,” said Dr. Michael Pardo, a postdoctoral researcher at Colorado State University and Save the Elephants.
“By contrast, our data suggest that elephants do not rely on imitation of the receiver’s calls to address one another, which is more similar to the way in which human names work.”
“The ability to learn to produce new sounds is uncommon among animals but necessary for identifying individuals by name.”
“Arbitrary communication — where a sound represents an idea but does not imitate it — greatly expands communication capability and is considered a next-level cognitive skill.”
“If all we could do was make noises that sounded like what we were talking about, it would vastly limit our ability to communicate,” added Colorado State University’s Professor George Wittemyer, chairman of the scientific board of Save the Elephants.
“The use of arbitrary vocal labels indicates that elephants may be capable of abstract thought.”
In their study, the researchers used machine-learning methods to analyze recordings of 469 calls (rumbles) made by wild African elephant female-offspring groups in the Amboseli National Park and Samburu and Buffalo Springs National Reserves in Kenya between 1986 and 2022.
The machine-learning model correctly identified the recipients of 27.5% of these calls, which they note is a higher percentage than the model detected when being fed a control audio.
They also compared the reactions of 17 wild elephants in response to recordings of calls that were either originally addressed to them or another elephant.
They observed that elephants approached the speaker playing the recordings more quickly and responded more vocally in response to calls originally addressed to them, compared to those originally addressed to another elephant.
This suggests that elephants recognize individual calls addressed to them.
“Our finding that elephants are not simply mimicking the sound associated with the individual they are calling was the most intriguing,” said Dr. Kurt Fristrup, a researcher at Colorado State University.
“The capacity to utilize arbitrary sonic labels for other individuals suggests that other kinds of labels or descriptors may exist in elephant calls.”
New insights into elephant cognition and communication revealed by the study strengthen the case for their conservation.
Elephants are classified as endangered, due to poaching for their ivory tusks and habitat loss from development.
Because of their size, they need a lot of space and can be destructive to property and hazardous to people.
“While conversing with pachyderms remains a distant dream, being able to communicate with them could be a gamechanger for their protection,” Professor Wittemyer said.
“It’s tough to live with elephants, when you’re trying to share a landscape and they’re eating crops.
“I’d like to be able to warn them: ‘Do not come here. You’re going to be killed if you come here’.”
A paper on the findings was published in the journal Nature Ecology & Evolution.
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M.A. Pardo et al. African elephants address one another with individually specific name-like calls. Nat Ecol Evol, published online June 10, 2024; doi: 10.1038/s41559-024-02420-w
