Toothed whales use their noses to whistle and click

Their nasal voices can range from creaky clicks to falsetto whistles

two underwater wild dolphins look back at the viewer

The mystery of how dolphins, porpoises and other toothed whales make noise has finally been solved.

Mike Hill/Stone/Getty Images

Dolphins, orcas and other toothed whales are very vocal creatures. They make super-loud, super-fast clicks. These beacon-like sounds echo off surrounding surfaces. This echolocation allows the animals to find prey in the total dark of the deep sea. These whales and dolphins also talk to each other through whistles and grunts. But until now, it has been a mystery just how they produce such a rich set of sounds.

New research shows that toothed whales make noise by blowing air through a unique structure in their nasal passages. And although these whales speak from the nose rather than the throat, their sound-making setup shares some features with our own. For instance, they make noises in three different vocal registers — vocal fry, chest and falsetto — just as people do. Researchers shared their findings March 2 in Science.

Image: The words “Wild Things: A Graphic Tale” are written in green block letters. A toucan perches on the W in ‘Wild,’ a jaguar sleeps atop the T in ‘things,’ the letter S in ‘things’ is a snake, and other animals surround the text.
Image: A sperm whale, a dolphin, an orca and a beluga poke their heads out of the sea to smile up at a blue sky while birds fly overhead. Text: How whales make noises with their noses. Written by Maria Temming, Illustrated by JoAnna Wendel.
Text (above first image): Toothed whales are total chatterboxes. They chirp out clicks for echolocation, which helps them hunt in the deep, dark sea… First Image: a beluga whale swims after a squid in dark waters. The whale is saying, “What’s on the menu today?” and the squid is saying, “Not me! Not me!” Text (below first image, above second image): …and they grunt or whistle at each other to team up for hunting, finding mates and more. Second Image: Two orcas swim near each other with their noses almost touching. One is saying, “You come here often?”
Text (above image): To find out how whales make these sounds, scientists used cameras to peer into the open blowholes of trained dolphins and porpoises. (A whale’s blowhole is like your nostril.) Image: A woman kneels at the edge of a pool to hold up a stick-shaped camera to the blowhole of a dolphin that is floating near the side of the pool with its nose on the edge. The woman is saying “Open wide!” Text (below image): This revealed how tissue moved inside the animals’ noses as they chattered away.
Text (above image): The researchers also used suction cups to stick sound recorders on wild dolphins, false killer whales and sperm whales. This allowed the team to eavesdrop on the sounds whales made throughout the day. Image: A scientist in cargo pants, a long-sleeved shirt and an orange life vest stands at the edge of a boat to use a long stick to put a suction cup on the back of a whale that is just poking out of the water. The scientist is saying, “Sorry this is a bit nosy!”
Text (above image): Toothed whales, they found, use a special set of tissue folds inside their nasal passages to make noise. “It’s a completely new structure,” says Coen Elemans, a biologist at the University of Southern Denmark in Odense. “No other animal has it.” Image: A diagram shows the inside of a whale’s head with numbers pointing to each step in the whale’s sound-making process. Step 1: Whale pushes air from its lungs into its nose, which is sealed off by the larynx. Step 2: Muscle pushes air through the phonic lips. Step 3: Phonic lips vibrate. Step 4: Vibrations travel through fatty tissue. Step 5: Fatty tissue vibrations send sound waves into the water.
Text (above image): The sound-making setup in toothed whales is similar to the way people talk or sing. We just blow air through vocal folds in our throats instead of our noses. Image: A child in an orange shirt and jeans stands next to the glass at an aquarium with a beluga whale on the other side. The child is singing “Baby beluga, baby beluga…” A diagram above the child shows how inside the child’s throat, vocal folds are vibrating to produce the song.
Text (above image): Elemans’ group also found that toothed whales use their nasal voice box to make sounds in three “vocal registers,” just like people. Image: a small white whale and a large grey whale face each other. Below them is a chart. The first column of the chart lists three vocal registers: Vocal fry, chest register and falsetto register. The second column of the chart depicts the sound wave for each vocal register. The third column lists what each vocal register sounds like in people: vocal fry corresponds to creaky voice, chest register is speaking voice, and falsetto register is singing voice. The fourth column lists what each vocal register sounds like in whales: vocal fry is echolocation clicks, chest register is bursts of sound, and falsetto register is whistles. Below the chart, two children face each other speaking, similar to the two whales above the chart.
Text (above image): Vocal fry is good for echolocation, because those sound waves all travel in one direction, like a flashlight beam. Image: A dolphin swims through a school of fish, chasing one. Orange lines beaming out from its nose illustrate the direction that its echolocation click sound waves are traveling. A speech bubble coming from the dolphin says, “Here, fishy fishy…” Text (below image): “That is really good if you want to catch animals,” Elemans says. “But it’s really bad for communication, because you send out signals only one way.”
Text (above image): Sound waves in the chest and falsetto registers spread out in every direction. “You can say something, and everybody will hear it,” Elemans says. Image: An orca and a sperm whale face each other. The orca says, “Why did the whale cross the ocean?” The sperm whale says, “Why?” The orca says, “To get to the other tide!” The sperm whale says, “Good one!”
Text (above image): So far, humans and crows are the only other animals known to use vocal registers. Image: a person in a canoe wearing a life vest and glasses has a crow perched on their shoulder and waves at a dolphin poking its head out of the water. The person says to the dolphin, “Welcome to the club!” Text (below image): Elemans hopes this new similarity between people and toothed whales “may create some more sympathy for these animals that were close to being wiped out by us and are luckily slowly recovering.”
JoAnna Wendel

Maria Temming is the Assistant Managing Editor at Science News Explores. She has bachelor's degrees in physics and English, and a master's in science writing.

JoAnna Wendel is a freelance science writer and cartoonist in Portland, Ore. She loves to make comics about all types of science, but she especially loves drawing planets, invertebrates and sea creatures. When she's not drawing, JoAnna is probably reading, hiking or hanging out with her cat, Pancake.

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