The Wonder of Snail Shells

The snow has only just melted off in a rush, leaving the bare ground of spring. Bits of green are beginning to show, the bunch grasses turning from humps of broken brown twigs to emerald clumps of new growth. Much of the earth lies naked, often red-brown from the clay so prevalent in the area, and always rich with the aroma of soil – a scent so full of life after a long, white, winter. On that bare ground lie treasures: stones and bones and bits of wood that will disappear as the grass and flowers surge up in summer. And there are the shells, white coils of calcium carbonate that stand out against the earth.

crop snailEach shell is a near perfect spiral, curving outward from an invisible center to spread into a flared opening, beautifully textured by delicate parallel ridges twisting along the coil. Some are bone white while others hold hints of brown woven deftly into the design. The shells are sculptures, works of intricate art. Made by snails.

When I was quite young, I believed the snail shells were fossils. I knew that across the valley, the Yellowstone volcanics hold petrified trees and delicate impressions of leaves and grass pressed into stone: plants from another time, odd species that don’t exist now, chinquapin and such. I knew that behind our ranch lie ancient fossils from the sea: impressions of shells, crinoids, and odd flotsam and jetsam left floating in what we now call the Madison Limestone. At that point, I didn’t know the details, the geologic ages, the names of the strata, but I knew there were ancient stories in the land. And so the white shells that litter the earth –  I thought they must come from the sea, left lying on the ground after layers of rock and sediment had eroded away.

I soon learned my belief was a fable, a story I created to connect the shells to the great length of time all around. I came to this understanding simply through observing living snails in brown shells tucked into nooks and crannies, camouflaged by the color of their newly sculpted abodes. Oh. Oh… The white shells? Not fossils, but cast off creations of creatures of today.

Since those early years, I’ve been captivated by the stories tied to fossils. How to explain fossils before science brought us modern geology? It’s a fascinating reflection on cultures.

In The First Fossil Hunters, Adrienne Mayor describes how early Greeks explained large fossilized bones through tales of great mythical creatures. The griffin, a huge beaked monster with wings and long talons, became a popular Greek motif around 700 BC. The Greeks created an entire natural history for this “extant” creature whose existence was based on Protoceratops bones found in Scythian gold mines. Fossil elephant skulls probably inspired the Cyclops of Homer’s Odyssey. These skulls have a large central nasal cavity, a hole that could easily be imagined as the single eye of a mighty monster.

Then, not much further on, the Greek poet Xenophanes of the 6th c. BC followed a philosopher-scientist way of thinking. Xenophanes observed marine fossils on mountains and concluded that water had covered the earth and the fossils were the remains of ancient sea creatures preserved in marine sediments. He was not afraid to look time in the eye.

Later came a time when fossils were explained as lusus naturae: jokes of Nature. Marjorie Nicolson writes of this in her wonderful book Mountain Gloom and Mountain Glory, attributing the idea to medieval thinkers who, basing their beliefs on the Bible, knew that marine animals could not have lived on dry land – God had created the earth and the sea separately on that third day. It seemed likely that the artistic shapes decorating rocks and cliffs were simply Nature “in a whimsical mood.”  It was a story told to fit the time, a contrast to Xenophanes’ more empirical theory. It also indicates the animate quality attributed to Nature in the ages before the Renaissance: Nature had a capricious streak, capable of playing jokes.

There are more stories, more attempts to explain the remnants of the past captured in stone. It seems we cannot help it; from Greek philosophers to small children standing in a field asking “Why?” we look around and wonder. I held white snail shells and tried to understand how they fit with the world I was just beginning to know. The mystery of the coiled shell, whorled and spiraling into an elegant piece of art, more complex than any eye can see, made my young questing mind find answers that took the shells into a bigger picture.

At some point, I reluctantly admitted that no matter how much they resembled the great nautilus fossils I’d seen in various museums, no matter how astounding their architecture, those graceful structures displayed on the earth of spring were nothing more than cast-off snail housing.

Which makes me sit back and wonder. For that, in and of itself, is quite miraculous.

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