Dolphins Show the Strongest Evidence of Calling One Another by Name

Some animals may use vocal labels for one another, but scientists are still debating when an animal sound qualifies as a name. The strongest evidence so far comes from bottlenose dolphins. Since the 1960s, researchers have known that young dolphins develop individually distinctive sounds called signature whistles. Playback experiments have shown that dolphins can recognize individuals from the frequency and structure of these whistles, even when another dolphin produces them. Dolphins also copy one another’s signature whistles to initiate contact, a behavior that resembles the way humans use names. Kelly Jaakkola, a cognitive psychologist at the Dolphin Research Center in Florida, told Live Science that dolphins appear to assign these whistles to particular individuals in a more symbolic way. The whistles are used within complex social groups and during cooperative activities. Other species offer intriguing but less conclusive examples. Playback experiments suggest that wild African elephants may direct distinctive low rumbles at specific individuals. In one study, elephants approached a speaker more quickly and vocalized more often when a rumble associated with them was played. That research appeared as a 2023 preprint and has not been peer-reviewed. Studies have also indicated that spectacled parrotlets may use vocal labels for other birds. In a separate survey of 800 parrot owners, roughly half reported that their birds used learned vocal labels for individual people or animals. Those observations, however, involved parrots living with humans and do not establish that the birds understand names in the same way people do. Marmosets are another disputed case. Researchers found that some calls were directed toward particular individuals and learned from family members. But a published response argued that the calls were correctly identified only 16% to 61% of the time, leaving open the possibility that the animals were imitating one another rather than using names. A July 2026 paper proposed three standards for identifying naming behavior across species: a call must refer to one individual, symbolically represent that individual to the caller, and have shared meaning between at least two animals. By those standards, dolphins currently provide the clearest evidence. Elephants, parrots and marmosets need further study. Researchers say name-like calls may be useful to highly social animals that can learn new sounds and often separate into smaller groups. Whether many other species use them remains an open question.