K2

Episode 03 · Animal communication

Do whales have vowels?

AI is revealing that sperm whales “talk” in a structured click-language — with rhythm, flourishes, and maybe even vowels.

PS

Pratyusha Sharma & Prof. Jacob Andreas · MIT CSAIL + Project CETI

Peer-reviewed in Nature Communications (2024) · ~9,000 whale codas

🐋 Project CETI📊 ~9,000 “codas”🤖 Decoded with AI❓ We can’t translate it yet

Watch & listen

Video brief

Plain-language · ~2 min

Watch on YouTube ↗

Audio brief

Single host · 1:36

Voices and visuals in these briefs are AI-generated.

At a glance

The whole study in one picture.

The “talk”
Codaspatterns of clicks
The data
~9,000codas, near Dominica
The tool
AI+ years of recordings
Clicks = “codas”
like Morse code
Combine like an alphabet
rhythm, tempo, flourishes
A huge “vocabulary”
maybe even vowels
What’s a “coda”?
A short burst of clicks — a whale’s basic unit of “speech.”
Can we talk to whales now?
Not yet. We’ve found structure, not meaning — we still don’t know what they’re saying.

Read it 3 ways

Same research, three lenses — pick yours.

Sperm whales chat in bursts of clicks called codas. New AI analysis shows those clicks are far from random — they carry the building blocks of a language.

Think of a coda as Morse code made of clicks. Studying about 9,000 of them from whale families near the Caribbean island of Dominica, researchers found four dials the whales turn: rhythm and tempo (the base beat), rubato (smoothly speeding up or slowing down), and ornamentation (sneaking in an extra click). Mix and match those, and you get a huge set of distinct “words” — a “phonetic alphabet.” A newer study even reports vowel-like sounds.

The catch: finding structure isn’t the same as understanding meaning. We still can’t translate whale, and whether this counts as true “language” is debated. But it reshapes how we think about animal minds.

Jargon decoder

Coda

A short, patterned burst of clicks — a unit of sperm-whale “speech.”

Click train

The stream of clicks whales make using their huge nasal “nose.”

Combinatorial structure

Small pieces combine in many ways to make many meanings — like letters into words.

Rhythm & tempo

The pattern and speed of the clicks — a coda’s basic identity.

Rubato

Smoothly speeding up or slowing down within a coda.

Ornamentation

Adding an extra click as a flourish, depending on context.

Phonetic alphabet

A small set of building-block sounds that combine into a big “vocabulary.”

Project CETI

The research effort using AI to study and decode whale communication.

Keep in mind

Structure isn’t meaning. We’ve shown whale clicks are richly patterned — but we still can’t translate them, and whether it’s a true “language” is debated.

Sources

Source: Sharma, P., Andreas, J., et al., “Contextual and combinatorial structure in sperm whale vocalisations,” Nature Communications (2024). MIT CSAIL & Project CETI. Read it ↗

Curated by K² Series. Voices and visuals in the briefs are AI-generated — always double-check before relying on them.

Do whales have vowels? | K² Series