BY THE OPTIMIST DAILY EDITORIAL TEAM
Dolphins have long fascinated scientists for their intelligence, empathy, and complex social behaviors. Now, researchers believe they may be on the verge of decoding a more intricate piece of dolphin communication: a system that bears resemblance to human language.
In a groundbreaking study, scientists at the Woods Hole Oceanographic Institution (WHOI), along with partner institutions like the Sarasota Dolphin Research Program (SDRP), have found the first potential evidence that bottlenose dolphins might use shared, word-like sounds known as non-signature whistles (NSWs).
“Bottlenose dolphins have long fascinated animal communication researchers,” said Dr. Laela Sayigh, the study’s lead researcher at WHOI. “Our work shows that these whistles could potentially function like words, shared by multiple dolphins.”
Beyond names: decoding the non-signature whistle
Much of past research on dolphin communication has centered around “signature whistles” (SWs), distinctive sounds used by individual dolphins as personal identifiers, similar to names. But NSWs, which make up about half of dolphin vocalizations, have remained largely understudied.
Thanks to a 50-year acoustic archive built by the SDRP in Sarasota, Florida, researchers were able to analyze the rarely examined NSWs. In their work, the team catalogued 22 distinct NSW types, including two whistles they labeled NSWA and NSWB, which are produced by at least 25 and 35 dolphins, respectively.
These shared whistles, unlike the individualistic SWs, are stereotyped; they repeat patterns that could serve as universal signals within the dolphin community.
A new whistle, a possible meaning
To study the function of these sounds, the team used underwater digital tags and suction-cup hydrophones to capture vocalizations from identified dolphins. They then conducted playback experiments in the wild to observe dolphin responses.
“We found that [NSWA] typically elicits avoidance responses, leading us to believe that it may have an alarm-type function,” Sayigh explained. The other call, NSWB, appears to function more like a query. “This whistle may be produced in response to an unexpected stimulus, perhaps as a way of inquiring what it is,” she said.
Sayigh emphasized that these interpretations are still hypotheses, noting that dolphins’ reactions to NSWB have been mixed. “Responses to playbacks of NSWB have been variable, which could support a variety of functions, including our suggested function as a query.”
Are dolphins using a form of language?
The implications of these findings are significant. Since dolphins are known for lifelong vocal learning, a rare trait among mammals, and use referential SWs, the researchers believe it’s plausible that NSWs are also learned and convey meaning.
“Our study provides the first evidence in dolphins for a wider repertoire of shared, context-specific signals, which could form the basis for a language-like communication system,” the study authors wrote.
Still, Sayigh is cautious. “We have only suggested that NSWs may be word-like, in the sense that they may have specific meanings that are understood by multiple animals,” she said. More research is needed to determine whether dolphins truly use language-like structures.
Global recognition for pioneering work
The study has earned the research team the inaugural Coller Dolittle Challenge prize. Jeremy Coller, the challenge’s founder, praised the team for helping bridge the communication gap between humans and animals. “Humans share this planet with millions of other species, but for far too long we’ve only talked among ourselves,” he said.
The researchers hope to use artificial intelligence to further analyze their extensive dataset and deepen our understanding of dolphin communication.
As Sayigh put it, “We don’t want to leave any patient behind, no matter how small they are.” Her sentiment reflects a growing scientific curiosity and ethical imperative to listen more closely to the creatures with whom we share the oceans.
