As kids, we learn that if you place a shell against your ear, it becomes an auditory portal to the ocean. It’s a powerful illusion as, merged with your ear, the shell creates an echo chamber of noises that transports us to breaking waves and sea breezes, creating a moment of intimacy and wonder between us and the natural world. Much as shells have done throughout human history, as journalist Cynthia Barnett writes in her exquisite new book, The Sound of the Sea: Seashells and the Fate of the Oceans. Since the dawn of humanity, our history has been inextricably tied to the pearlescent, the ribbed, the spiraling, the speckled, and the iridescent calcium carbonate wonders and the unsung animal artists of the ocean that create, inhabit, and leave them behind.
Shells are the legacies of some of the world’s most inventive and prolific architects: mollusks. Biomineralization, the process by which these animals recycle ocean minerals into hard protective structures, evolved in microorganisms more than 500 million years ago, which eventually gave rise to the tens of thousands of known mollusk species today. These soft-bodied creatures have, quite literally, shaped the world as we know it. As Barnett writes, “We walk on a world of shell.” From limestone aquifers, to chalk, to marble, shells made by soft-bodied animals are the foundation for much of life on earth and are a blueprint for our ever-changing planet, their fossils even documenting Mount Everest’s more humble origins in the seas.
