Carl Zimmer reports via the New York Times: Ever since the discovery of whale songs almost 60 years ago, scientists have been trying to decipher their lyrics. Are the animals producing complex messages akin to human language? Or sharing simpler pieces of information, like dancing bees do? Or are they communicating something else we don't yet understand? In 2020, a team of marine biologists and computer scientists joined forces to analyze the click-clacking songs of sperm whales, the gray, block-shaped leviathans that swim in most of the world's oceans. On Tuesday, the scientists reported that the whales use a much richer set of sounds than previously known, which they called a "sperm whale phonetic alphabet." In the study published in the journal Nature Communications, researchers found that sperm whales communicate using sequences of clicks, called codas, that exhibit contextual and combinatorial structure. MIT News reports: The researchers identified something of a "sperm whale phonetic alphabet," where various elements that researchers call "rhythm," "tempo," "rubato," and "ornamentation" interplay to form a vast array of distinguishable codas. For example, the whales would systematically modulate certain aspects of their codas based on the conversational context, such as smoothly varying the duration of the calls -- rubato -- or adding extra ornamental clicks. But even more remarkably, they found that the basic building blocks of these codas could be combined in a combinatorial fashion, allowing the whales to construct a vast repertoire of distinct vocalizations.

[...] By developing new visualization and data analysis techniques, the CSAIL researchers found that individual sperm whales could emit various coda patterns in long exchanges, not just repeats of the same coda. These patterns, they say, are nuanced, and include fine-grained variations that other whales also produce and recognize. "One of the intriguing aspects of our research is that it parallels the hypothetical scenario of contacting alien species. It's about understanding a species with a completely different environment and communication protocols, where their interactions are distinctly different from human norms," says Pratyusha Sharma, an MIT PhD student in EECS, CSAIL affiliate, and the study's lead author. "We're exploring how to interpret the basic units of meaning in their communication. This isn't just about teaching animals a subset of human language, but decoding a naturally evolved communication system within their unique biological and environmental constraints. Essentially, our work could lay the groundwork for deciphering how an 'alien civilization' might communicate, providing insights into creating algorithms or systems to understand entirely unfamiliar forms of communication."