Humans Are Not the Only Animals That Use Names
Elephants, bottlenose dolphins, marmosets and green-rumped parrotlets join humans in calling each other by name, researchers say
- By Barry Yeoman
- Wildlife Science
- Jun 25, 2025
Illustration by .
EVERY MORNING AFTER BREAKFAST, left the camp at Kenya’s Samburu National Reserve and set out looking for African savanna elephants. With an assistant at the wheel, the behavioral ecologist would ride through the open grasslands or head toward the doum palms lining the Ewaso Ng’iro River. When they spotted a family of females and calves from their study group, the researchers would park, and Pardo would set up a microphone on a boom pole. They would then climb onto the roof of the Land Cruiser. And they would wait for the animals to start calling to one another.
Pardo, then a postdoctoral fellow at Colorado State University, knew how to identify individuals by features like the nicks and tears on their ears. When he heard the elephants vocalize, he noted the identities of both the caller and the recipient. He observed what the elephants were doing—making contact across a distance, for example, greeting each other up close or taking care of a calf.
Pardo hoped that by collecting this information, he could start to answer a question: Do elephants call one another by name?
The answer could offer clues to the evolution of language—a mystery to scientists and the source of considerable contention. Many scholars call language a uniquely human phenomenon that originated in our species. The eminent linguist Noam Chomsky even proposed that it arose from a single genetic mutation. But “big bang” events are not how evolution typically works, argues , a neuroscientist at the Hebrew University of Jerusalem. Omer says there should be at least traces of language in other animals. Scientists like Pardo are now looking for those traces.
One hallmark of language is that we assign “vocal labels” to objects, concepts and one another. This thing is called a box. These disparate objects in the box are all called toys. This child playing with the toys is called Wren. Personal names are a type of vocal label that, like language, must be learned. This is one reason why scientists want to know whether other animals use names too.
Pardo collected more than 400 recordings of the deep rumbles that constitute most elephant calls. The majority came from his own fieldwork in Samburu and adjacent Buffalo Springs National Reserve from late 2019 through April 2022. Others, recorded over 20 years, came from a colleague who worked 300 miles away. Pardo used some of these data to train a machine-learning algorithm—a simple type of artificial intelligence—to identify the recipient of an elephant’s call based on the acoustic patterns of the rumble.
The algorithm then analyzed the rest of the calls. Over several rounds of testing, it identified the recipients with far more accuracy than random guessing would have produced. This suggested that encoded somewhere in those complex rumbles (he doesn’t know exactly where) were names for individual elephants. Additional tests helped rule out other explanations—that the algorithm was guessing based on the type of relationship between the caller and the receiver, for example.
Pardo still wanted to know whether those names were meaningful to the recipients themselves. So he played back the recordings to 17 elephants, anywhere from eight days to more than two years later. When an elephant heard two rumbles produced by the same caller—but addressed to different recipients—it seemed to discern which of the calls was meant for itself. It approached the loudspeaker sooner, if it approached it at all, when it was the intended recipient. It responded with its own vocalizations faster. And it vocalized more.
This strengthened Pardo’s conclusion that the rumbles contained individual names. He and several colleagues from the nonprofits and published their in the journal Nature Ecology & Evolution in June 2024.
In Kenya’s Samburu National Reserve, behavioral ecologist Mickey Pardo and Save the Elephants researcher James Mpapa record calls of elephants (below) to learn if the animals use and recognize individual names for one another.
What’s in a name?
Pardo, now a postdoc at Cornell University, was originally inspired by research he had read on wild and captive bottlenose dolphins. Scientists have long known that young dolphins create unique whistles, called signature whistles, that they repeat over and over. In her , behavioral biologist described how, when mothers and calves—or adult male friends—are separated, the dolphins call out to one another by imitating the recipient’s whistle.
This “whistle matching,” which other scientists also had observed, is not verbatim copying. “They are taking that whistle and riffing,” says , a behavioral biologist at Stephen F. Austin State University in Texas.
The following year, Bruck that in zoological settings remembered signature whistles of former pool mates for as long as 20 years. When played recordings of dolphins they once knew, the animals spent more time approaching and looking at the underwater speakers than when they heard strangers’ whistles.
Bruck wasn’t convinced yet that the dolphins remembered one another—only that they remembered particular whistle patterns. But later he conducted an experiment where dolphins heard a familiar whistle and simultaneously tasted a familiar dolphin’s urine. (Urine tasting is also documented in the wild.) When the whistle and urine matched, the dolphins hovered around the speaker for longer.
“The dolphin is telling you, not only do I know that tune, but I know who that tune belongs to,” says Bruck, who the results in 2022 in Science Advances. He compares this to hearing a friend’s name and remembering the smell of their perfume. Bruck has even seen dolphins whistle the signatures of acquaintances whose urine they’ve just tasted. “That’s what humans do,” he says. “We talk about each other. We gossip.”
When Pardo read King’s thesis, he wondered if elephants might also use names. “We know that dolphins and elephants are among the few species of mammals that are capable of learning to imitate completely novel sounds,” he says. (In fact, an elephant at South Korea’s Everland Zoo had made by mimicking five Korean words.) “I thought maybe names could be one of the explanations why elephants have this unusual ability.”
To Pardo, what distinguished the two species was that dolphins named themselves by developing the signature whistles. With elephants, it was more of a mystery—how do they derive their names?
Here, the machine-learning algorithm proved useful again, because it predicted the recipients of different types of calls with different levels of accuracy. When the elephants were locating each other across a visual obstruction, the algorithm correctly identified the callers an impressive 42 percent of the time. When the elephants greeted each other up close, the algorithm only succeeded in 4 percent of cases, suggesting that the animals use names when visual recognition is not possible.
But the algorithm also scored 47 percent accuracy for caregiving rumbles made by an adult or adolescent female toward a calf. Most of these were “coo rumbles,” produced when the older elephant was touching or nursing a calf, or reassuring a calf in distress.
One possible explanation is that adults use these caregiving rumbles to teach young elephants their names. “That’s just a hypothesis,” Pardo says. “But anecdotally, we’ve observed elephants shortly after giving birth. They often make coo rumbles to the calf over and over and over again. This could be some kind of vocal imprinting, where the calf basically learns their name from the coo rumbles.”
Elephants wouldn’t be alone in learning their names from adults. , a behavioral ecologist at the University of Texas Rio Grande Valley, works with wild green-rumped parrotlets in Venezuela. These small parrots have signature contact calls that, when imitated, also seem to serve as names. When Berg swapped some of the birds’ eggs between nests, he that the chicks sounded more like their adoptive parents than their biological ones. “That’s pretty strong evidence that they’re mimicking or imitating their foster parents,” he says.
Common marmosets rest in the canopy of a Brazilian rainforest. When these tree-dwelling monkeys lose sight of family members, they communicate with high-pitched whistles, or phee calls, that scientists suggest include an individual’s name. In Venezuela, this wild green-rumped parrotlet chick (below) is 21 days old, the age when it will learn its signature contact call, or name, from its parents.
Precursor to language
The different species known to call each other by name are so far apart on the evolutionary tree that they likely acquired their abilities independently. “Elephants are basically as evolutionarily diverged from humans and dolphins as it is possible for a placental mammal to be,” says Pardo. “Their lineages are separated by something like 100 million years.”
By contrast, most nonhuman primates are not known to use individual names. Chimpanzees, to the best of scientists’ knowledge, do not. Nor do orangutans or bonobos. But last year, Omer, the Israeli neuroscientist, announced he had found an exception.
Omer studies the brains of common marmosets, small tree-dwelling monkeys with social structures similar to ours. Marmosets live in small families that typically consist of two monogamous parents and their offspring. These families are crucial to survival. “So it’s a perfect animal model for human social behavior,” he says.
Marmosets inhabit dense South 皇冠体育app官网平台n rainforests where it’s easy to lose sight of one another. When they do, they communicate with a loud whistling pattern called a “phee call.” (Like humans in polite conversation, the marmosets take turns.) Just as the elephant’s deep rumble is suited for long-distance signaling, the marmoset’s high-pitched phee call is ideal for reaching a family member who’s nearby but shrouded by dense foliage.
Omer was hardly the first researcher to study marmoset communication; other scientists knew that phee calls contained information about the caller. But no one had looked for information about the receiver, he says. The reason, he believes, was the prevailing dogma: that monkey communication is “primitive, nonflexible and innate.”
In the laboratory, it’s easy to get marmosets to produce phee calls: You put them in the same room, let them see each other and then lower a curtain between them. In Omer’s lab, that room is equipped with microphones, cameras and speakers.
Because marmosets vocalize so freely, Omer was able to record 54,000 phee calls. From there, his research paralleled Pardo’s elephant work. He trained a machine-learning algorithm to analyze the recordings. The algorithm correctly predicted the recipient most of the time. And when the monkeys listened to the recordings, they responded more reliably to calls that were originally directed at them.
Omer also set out to learn how marmosets learn one another’s names. What he concluded was that they eavesdrop on conversations among family members. “You’re listening to Monkey A calling Monkey B,” he says. “You’re Monkey C. Then you’re imitating Monkey A.”
Scientists call this process vocal learning and consider it a precursor to language. “This is a very important high cognitive function,” Omer says. “Everybody agrees that in order to develop language, you have to have this fundamental ability.” That doesn’t mean human language evolved from marmoset calls; the species diverged about 35 million years ago. Rather, Omer says, the skill evolved separately in two species with similar social structures. The neuroscientist his findings in Science in August 2024, two months after Pardo’s elephant paper.
Biologists are only starting to learn how animals use personal names. “If we really want to understand how names evolve, we would probably need to find a few more species that have this ability,” says Pardo. “And then we would need to do some kind of formal analysis to try and understand how [their] different ecologies impacted the evolution of this trait.”
To Pardo, there is an ethical component to the work. Given how firmly we once believed that people hold a monopoly on names, the recent discoveries chip away at the human exceptionalism that undergirds how we treat animals. “When we find behaviors like this,” he says, “it starts to break down the species barrier—the sense that most people have that humans are somehow superior in moral worth to other species.”
This, he quickly adds, doesn’t mean that animals that use names deserve more protection from harm than animals that don’t. But it is easier to empathize with other species when we understand what we have in common. And it’s harder to brush off all nonhuman creatures as nameless others—when some of them, literally, are not.
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