Sanibel Island, on the Gulf coast of Florida, is famous for a number of things: beautiful shore birds, long white sand beaches and postcard sunsets. But most of all, it’s famous for its seashells. Because of the unusual angle of the island in relation to the Florida coast, Sanibel acts as a giant sieve, harvesting huge numbers of shells from the depths of the sea and leaving them on the sand.
I haven’t been to Sanibel for years, but I still remember something my father said to me on a shell-rich beach one morning when I was six or so. The beach was crowded with other vacationers. They stooped and picked among the gleaming shoals of shells at the edge of the water, tucking the good ones away in baskets to take back to their homes in other states, other countries. My father bent down and picked up a small pink-and-white shell.
“Isn’t it amazing that this,” my father said, holding the suddenly unique and consequential shell out to me, “can come from that.” He pointed out to the whole huge sweep of sea before us.
It was a simple enough statement, but behind it was a world of mystery. By offering up something so perfect, the sea makes a very un-sealike gesture. After all, the ocean is beautiful, but it is also huge, violent, and in its way, terrifying (the Bible endlessly uses it as a symbol of chaos for good reason). But the shell carries a message. It stands out, as the poet Paul Valéry put it, “from the common disorder of perceptible things.” When you think about it—and my father obviously had—the seashore is the last place you would expect to find such an elegant, perfect object.
The shell might be the world’s first souvenir. Seashells have been found at ancient archaeological sites hundreds of miles from the nearest ocean, showing that even in the earliest periods, people felt the desire to collect and keep them, just the way we do today. The Camino de Santiago, the celebrated pilgrimage that ends in the Spanish city of Santiago de Compostela, the legendary resting place of the Apostle James, has for centuries featured a scallop shell as its emblem. No pilgrim returns from the journey without such a shell as a memento of its successful completion. For hundreds of years, the Huichol Indians of Western Mexico have journeyed to the distant Pacific, where they collect shells and bring them back with them into Mexico’s interior to use in their sacred art.
Even scientists, not always given to choosing the most poetic way of explaining things, have been taken aback by the inspired nature of the shell’s design. One of the shells most studied and remarked upon by scientists is the chambered nautilus of South Pacific seas. Actually not a snail, as most shell-producers are, but a cephalopod—the animal family that includes the octopus and squid—the nautilus uses its shell as both a house and a flotation device. Each new watertight segment the nautilus builds as it grows is a third larger than the segment before it, and conforms to a mathematical formula called the golden ratio.
For reasons completely unknown, the golden ratio appears in countless natural designs, from sunflower florets to the hexagonal patterns on the skin of pineapples. Structures patterned on the golden ratio are mysteriously pleasing to the eye, and the formula appears also in such human creations as the pyramids of Egypt, the Parthenon in Greece, and even Leonardo’s “Mona Lisa.”
As mysterious to science as the mathematical intricacy underlying the shell’s spiral structure is the persistent question of why cells take such a dazzling array of shapes and patterns. Bright and colorful patterns in animals often attract the opposite sex. But as the world’s shell-bearing mollusks don’t possess eyes sophisticated enough to register such patterns, this explanation doesn’t hold up. Vibrant colors can also be used by animals as warning signals: a ways of saying, “Stay away from me, I’m dangerous. ” This explanation doesn’t apply to the shell either, however, because as nature writer Hilda Simon points out, Many snails with bright colors are coveted food items.” Science’s best stab at accounting for the shell? Simon quotes the famous Swiss zoologist Adolf Portman, who has said that shells might be the snail’s “self-expression.”
But whatever message the shells of the world present to other animals, the one they hold out to us is, to my mind, still best explained by what my father said to me that day on the beach at Sanibel. Like the ocean, life itself is turbulent and chaotic—full of winds and waves and unexpected storms. Yet behind this not always tranquil world, there lies another one, of beauty and harmony and heavenly perfection. It’s a world we get reminded of when, walking on the beach, we look down and see a little piece of it right at our feet.