Sonic Hieroglyphics and Acoustic X-Ray Vision: The Fascinating Science of How Dolphins and Whales Communicate

The secret language that the oceans speak: How Victorian Astronomy was able to decode it.

Sonic Hieroglyphics and Acoustic X-Ray Vision: The Fascinating Science of How Dolphins and Whales Communicate

“Words are events, they do things, change things… they feed energy back and forth and amplify it,” Ursula K. Le Guin wrote in her uncommon ode to the magic of real communication. “They feed understanding or emotion back and forth and amplify it.”

For millennia, we have considered language — the magic-box of words — the hallmark of our species. In the very last seconds of evolution, we have begun to recognize our own self-referentiality and to consider other forms of communication that might be able to transmit the magical energy of living creatures sharing what it’s like to live in the present moment.

Since the first time we looked up into the night sky, declaring the scattered stars the entirety of the universe and placing ourselves in its center, we’ve mistakenly believed that our senses were the only limit to what is possible. Our creaturely limitations have greatly limited our ability to grasp reality.

It is no surprise that an amazing underwater language was not discovered by human beings for most of the history both of our species’ and of science.

Art since Year of the Whale (1949).

James Nestor’s fascinating and very interesting book Deep: Freediving Renegade Science and What the Ocean Says About Us (public library) contains these words:

In a world of seven billion people, where every inch of land has been mapped, much of it developed, and too much of it destroyed, the sea remains the final unseen, untouched, and undiscovered wilderness, the planet’s last great frontier… the last truly quiet place on Earth.

It is quiet, but only if truth can be seen through our eyes. Down in the indigo waters, in what Else Bostelmann called “the submarine fairyland” as she brought the undersea world to the human eye for the first time, symphonies of speech mute to us bellow across immense distances, carrying messages as urgent and delicate as danger and identity. Now, a century of science and compassionate curiosity later, we know that dolphin mothers will whistle a sound patter over and over to a newborn — a kind of christening, imprinting the baby with its given name.

The Art of Field Book of Giant Fishes, 1949. This print is also available as a face-mask.

Dolphins and whales — the aquatic mammals collectively known as cetaceans — have some of the largest and most complex brains on our pale blue dot. A century after the great nature writer Henry Beston called on us to rise to a different and wiser concept of animals, for they move through this world “gifted with extensions of the senses we have lost or never attained, living by voices we shall never hear,” we know that the dolphin neocortex — the part of the brain tasked with problem-solving and higher-order thinking — is proportionately larger than ours, and that dolphins communicate in a strange and wondrous language we are only just beginning to decipher. Nestor explains the amazing creaturely mechanics that make up its magical magic.

Dolphins don’t have vocal cords or larynxes, so they can’t vocalize in a way that sounds like human speech. Instead, they use two small mouth-like structures embedded in their heads — vestiges of what were once nostrils. The dolphin can flex and bend these nasal passages, called phonic lips, to create a variety of sounds — whistles, burst pulses, clicks, and more — in frequencies that range between 75 and 150,000 Hz.

Of these, we can only hear the slenderest fraction in the lowest register — while humans can produce sounds up to 20,000 Hz, our everyday speech falls into the paltry 85-300 Hz range. One of the greatest things about us is our indomitable refusal to accept limitations placed on our creativity and hunger for truth. “We have a hunger of the mind which asks for knowledge of all around us,” the pioneering astronomer Maria Mitchell observed when a new generation of powerful telescopes began revealing cosmic truths far beyond what our naked eyes could see, “and the more we gain, the more is our desire.”

The spectra of light sources taken from an 19-century French physics textbook. Available as both a print or as a face-mask.

It was a tool of her era, invented for her field — the spectrograph, first used to analyze the light of Vega, the star that a quarter millennium earlier had anchored one of Galileo’s most ingenious experiments refuting the geocentric model of the universe — that scientists applied to sound a century later to detect and decode the language of underwater mammals. Recording the high-frequency clicks and whistles of dolphins, inaudible to human ears, and playing the recordings back through a spectrogram, humans were able to perform a feat of mechanical synesthesia and see for the first time the sound of language-rich silence — sound waves that looked, in Nestor’s lovely poetic image, like “a primitive form of hieroglyphics.”

Cetaceans have an evolutionary legacy that gives them a sounding ability that is as amazing as suprasonic hieroglyphics. Their echolocation capability, which they are blessed with jaws capable of high-definition sonograms, makes this sonic marvel possible.

Nestor considers the alien nature of this kind of listening and how much scientific innovation it will take for us to develop a prosthesis that expands our ability to use these superhuman levels of sensory perceptions.

Sound doesn’t travel in a straight line, the way it looks on a spectrogram, but instead expands in three dimensions, like a mist. Ears only process sound from two channels; cetaceans have the equivalent of thousands of channels that can collect this mist from all directions… For humans to perceive sonographic images through echolocation isn’t easy. Researchers would first need an artificial jaw made with thousands of mics that mimic tiny receptors. Then, they’d have to build a computer to process the collected data.

Globicephalus melas, or, long-finned pilot whale — a large species of oceanic dolphin — from A Book of WhalesFrank Evers Beddard 1900. This print is also available as a mask for the face.

For us, what is a miracle and a great triumph of technology is for cetaceans, it is a daily survival in a dark world. Nestor describes how the remarkable otherness of cetaceans’ physiology makes them both kin- and alien.

The echo information is received by the cetacean with the help of the fatty sac under the lower jaw. This fatty sac is a great source of data for cetaceans, as it provides thousands of points in addition to the two direction sources that ears provide. This allows the animal to calculate the size, shape, depth, interior and exterior dimensions of all the creatures and objects around it.

From six miles away, dolphins are able to detect larger objects’ shape, size, and position. Their echolocation is so powerful and sensitive that it can penetrate over a foot deep into sand; it can even “see” beneath skin. The brains and lungs of dolphins are able to be seen by other animals. With all this information, scientists believe dolphins can create the equivalent of an HD-quality rendering of objects nearby — not only where these objects are, but how they look from the inside out. Dolphins and other cetaceans can see X-rays.

Art since Year of the Whale (1949).

Complement with the wondrous world of octopus consciousness and the science of how trees communicate, even newer to us and our scientific tools than the science of cetacean communication, then revisit Year of the Whale — the poetic 1969 book about the mysterious lives of our planet’s largest creatures — and artist Jenni Desmond’s tender science serenade to the blue whale.

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