Sperm whales may shape their clicks into something closer to speech than code. New research from UC Berkeley linguists and Project CETI suggests their calls contain vowel like structures with a human style complexity that challenges long held assumptions about animal communication.<\/p>\n
In a new acoustic and computational linguistics study in the journal Open Mind, published November 2, 2025, Ga\u0161per Begu\u0161 and colleagues in UC Berkeley’s Department of Linguistics and Project CETI analyzed more than a thousand tagged recordings of sperm whale codas, the rhythmic click sequences whales use to communicate. By focusing on the spectral shapes of those clicks, they uncovered two recurring vowel like patterns and several diphthong like sweeps across individual codas, revealing a layer of structure far richer than timing alone.<\/p>\n
For decades, whale codas were thought to operate like an underwater telegraph, defined by how many clicks each coda contained and the spacing between them. That view held that meaning, if it existed, lived mostly in rhythm. But when the team stripped away timing and examined each click as a resonant event, the picture shifted. Codas sorted neatly into two spectral types, one with a single resonant peak and one with two, echoing the difference between human vowels like “a” and “i.” Just as striking, those patterns stayed consistent across many whales and across different coda types.<\/p>\n