“The book of love is full of music,” sings Peter Gabriel. “In fact, that’s where music comes from.”

The book of love is written in the language of wonder — our best means of loving life more deeply. To love anything — a person, a pond, the world — is to see the wonder in it, to hear the music in it. Both love and wonder are in mysterious conversation with the deepest substrate of us, the complete message of which is unintelligible to the analytical mind, inaccessible by any explanatory model. Both require a surrender to the musicality of the experience — a trust that the music is the message.

In the late 1960s, just before philosopher Thomas Nagel challenged our notions of more-than-human consciousness with his catalytic essay “What Is It Like to Be a Bat?” and long before Robert Macfarlane challenged our notions of animacy by asking whether a river is alive, the Finnish sound researcher Antti Jansson began wondering about the inner life of water, of its unheard creatures. As John Cage was discovering the musicality of silence while listening to his own nervous system in a sensory deprivation tank, Jansson — possibly a distant relative of beloved Moomins creator Tove Jansson — discovered the musicality of ponds. He grew particularly interested in the water boatman beetle Cenocorixa, capable of producing an astonishing 85 decibels — the noise level of New York City traffic — by rubbing its genitalia against its own body, much as cicadas play themselves.

Here was a whole new universe of bioacoustics, never before heard by human ears.

Half a century later, philosopher and musician David Rothenberg picked up where Jansson left off, bringing rigor and tenderness to the world of animal sounds. After his fascinating exploration of why birds sing, he turned his compassionate curiosity to the most neglected recesses of nature’s sonic consciousness — the ponds that punctuate forests, savannas, and suburbs alike.

As the human world grew quiet in the early pandemic, Rothenberg decided to drop a hydrophone into his local pond and just listen. To his astonishment, he discovered a portal into a secret universe of what he calls “undersound,” evocative of Rachel Carson’s landmark 1937 essay Undersea, which invited the terrestrial imagination for the first time to consider the hidden lives of the water world.

“In the great silence of the brackish waters behind our homes,” he heard the voices of myriad unknown creatures joining together in something between the buzzing of the nervous system in an anechoic chamber and the wistful moan of the gyaling, the Buddhist oboe. He heard photosynthesis itself — the regular rhythm of plants exchanging oxygen through the water, a metronome for the wild symphony orchestra of insects. And all of it he rendered in sonograms — maps of sound frequency against time — revealing the layered complexity of undersound, “music between, music no one species could make alone.” He writes:

Go deep looking for one sound and you may find the meaning of all of them. Everything sings, everything sounds; it all swirls around us together.

Hungry to discover more of this bioacoustic cosmos, he traveled to ponds all over the world, recording the bubbling of a passing turtle in Russell Wright’s Lost Pond in upstate New York and the late-night underwater calls of the painted frog in a pond at the Botanical Garden of Paris.

Soon, as cellist Beatrice Harrison had done with the nightingales a century earlier in what became the world’s first recorded interspecies musical collaboration, Rothenberg began accompanying the pond orchestra — sometimes with his beloved contralto clarinet, sometimes with electronic instruments.

It is mysterious, this universal impulse to join in with music, to sing along, to dance together. Conversation doesn’t seem to impel us in the same way. There, the impulse is often to counter and contradict rather than harmonize. Peter Gabriel articulates this perfectly when he runs into Rothenberg at an MIT conference:

With music, people dance, fall in love, sing along. With words on a page, you make enemies. People turn their back on you and get ready to argue.

Perhaps this is because music trades in mystery, while conversation trades in opinion — that subterranean species of certainty. Rothenberg’s undersound is a “cavalcade of lilting unknowns” — no sonogram can discern exactly which creature makes which sound and for what reason. A century and a half before him, Thoreau had captured this while pacing Walden Pond:

All sound heard at the greatest possible distance produces one and the same effect, a vibration of the universal lyre, just as the intervening atmosphere makes a distant ridge of earth interesting to our eyes by the azure tint it imparts.

In his fascinating multimedia record of the project, Secret Sounds of Ponds (public library), Rothenberg reflects:

I have long been fascinated by the sounds made by other creatures on this planet, wondering how we can engage with them without explaining them all away. I never wanted to translate the language of birds, whales, or bugs, but always wanted to join in with them in some uncertain way.

Peter Gabriel is right, if you hear the world as music, you can sing along with it, join in with it, celebrate and dance with it even while never knowing precisely what is going on.

[…]

Those sounds right at the edge of our comprehension might in fact become the most interesting… That is why music is more accessible than language… It just is, beaming to us from the thrum of the world, the universal lyre inside of everything, this animate Earth, this booming, living pond.

This, I suppose, could also be said of love — it just is, a bloom of aliveness within us and between us. Rothenberg’s project, for all its originality at the crossing point of art and science, is above all an act of love — a reverent reminder that we are here to play our small, indispensable part in the symphony of life and to listen wonder-smitten to our co-creation.