Scientists Discover a ‘Phonetic Alphabet’ Used by Sperm Whales, Moving One Step Closer to Decoding Their Chatter

Researchers used artificial intelligence to spot patterns in recordings of the marine mammals’ vocalizations, uncovering the “building blocks of whale language”

Sperm whale with calf underwater
Sperm whales communicate by making clicks. Westend61 / Getty Images

Sperm whales are highly social creatures that roam the world’s oceans together, diving deep in search of giant squid, their favorite food.

As they swim and hunt, these massive marine mammals communicate by making a series of rapid clicks that sound like a combination of “Morse code and popcorn popping,” writes NPR’s Lauren Sommer.

Now, with help from artificial intelligence, scientists are starting to unravel some of the mysteries surrounding the sperm whale communication system. They found a plethora of sounds they’ve termed a “sperm whale phonetic alphabet,” raising the possibility that the mammals have their own language, just like humans.

Researchers described their findings Tuesday in the journal Nature Communications.

The new paper is the result of a collaborative research effort called Project CETI, which stands for “Cetacean Translation Initiative.” With the initiative, researchers were curious to know if advancements in machine learning and computing could help make sense of whale vocalizations.

Scientists recorded a clan of 400 sperm whales in the Eastern Caribbean between 2005 and 2018, and they estimate at least 60 individuals ended up on the recordings. Using advanced computer algorithms, they detected patterns in the sounds—suggesting sperm whale communication may be more complex than previously assumed.

Sperm whales rattle off a series of rapid-fire clicks that researchers have named “codas.” Each coda consists of between three and 40 clicks. In addition to changing the number of clicks they make in quick succession, whales often speed up or slow down the tempo of each coda—researchers call this “rubato.” Sometimes, they add an extra “click” at the end of a coda, which scientists call “ornamentation.”

Exploring the Mysterious Alphabet of Sperm Whales

In the end, the team identified 156 distinct codas, each with its own rubato, ornamentation, tempo and rhythm. On their own, these codas may simply be meaningless sounds. But when combined, they could add up to something akin to syllables, words or even sentences.

“We’re now starting to find the first building blocks of whale language,” says study co-author David Gruber, a marine biologist and the founder of Project CETI, to the Associated Press’ Maria Cheng.

Researchers still don’t know what the repertoire of clicks means, if anything. One possibility is that sperm whales are using the clicks as a form of language. But it’s also possible the noises are more like music, which can “have a strong influence on emotions without it actually conveying information,” says Taylor Hersh, a bioacoustician at Oregon State University who was not involved in the research, to the New York Times’ Carl Zimmer.

Now that they have the sperm whale phonetic alphabet, researchers can proceed with figuring out how its different components fit together—and, possibly, what it all means.

“Once you have this combinatorial basis, it allows you to take a finite set of symbols [and] compose them to create an infinite number of symbols by following a set of rules,” says study lead author Pratyusha Sharma, a computer scientist at MIT, to New Scientist’s Clare Wilson.

For example, in the future, researchers might be able to match vocalizations with specific behaviors. That may not produce an exact one-to-one translation from whale to human language, but it would be “an amazing achievement” all the same, says Diana Reiss, a psychologist and animal behaviorist at the City University of New York who was not involved in the project, to the Associated Press.

Learning more about how sperm whales communicate may also be important for conservation. Categorized as “vulnerable” by the International Union for Conservation of Nature, sperm whales are still recovering from commercial hunting by humans in the 19th and 20th centuries. Though such whaling has been banned for decades, sperm whales now face new threats, including human-caused climate change, increased ocean noise, collisions with ships and entanglement in fishing gear.

If researchers knew what sperm whales were saying, they might be able to come up with more targeted approaches to protecting them, researchers suggest. In addition, drawing parallels between whales and humans via language might help engage the broader public in conservation efforts.

“When we can talk about whales and how important their grandmothers are, or how important being a good neighbor is, or the importance of cultural diversity in society, that really resonates with people and can drive change in human behavior in order to protect the whales,” study co-author Shane Gero, a biologist at Carleton University in Canada and founder of the Dominica Sperm Whale Project, tells NPR.

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