Stunning shells too beautiful for their own good
"Before you do anything else," curator Chris Meyer said the minute I arrived at the National Museum of Natural History's Invertebrate Zoology collection, "you have to vote for beauty."
He led me through a maze of cabinets to a counter laid out with a wire bingo cage and dozens of cowrie shells. Meyer instructed me to spin the cage five times and read out the numbers that appeared, then handed me a box containing the five corresponding shells.
Nestled in their box, the cowries reminded me of a child's marble collection. Each oblong shell had the same basic shape: a rounded, impossibly smooth top and a flat bottom with a slit-like opening in the center. The smallest was no bigger than my thumbnail, with green and brown speckles dotting its slick surface. The largest was as big as my palm. It had a lovely orange hue, and I flipped it over to reveal an opening edged with fine purple teeth.
I was supposed to rank the shells from most beautiful to least. Later, Meyer would add my ranking to a database that he is using to pinpoint trends in visitors' conception of beauty.
I found it difficult to choose a favorite.
"They are spectacular," Meyer agreed, "They're like nature's gems."
Drawn by their exquisite appearance, humans have been collecting cowries for tens of thousands of years. They may well be the original collected objects — the prehistoric predecessors to diamonds and gold. The oldest examples of jewelry ever found, dating back as early as 100,000 years, were made of cowries and other shells. As time went on, cowries became symbols of power and a form of currency.
European explorers filled their curio cabinets with the creatures. Today, collectors search the tropics in search of ever-rarer and more perfect specimens.
"For whatever reason, people are just fascinated," Meyer said. "And that's what we're trying to understand. What is it that is attracting people to have this fascination? What do people value about them?"
A cowrie, or any natural object, can be valued in a number of ways. There's the obvious metric, price, which for cowries is inextricably tied to their beauty. The most magnificent cowries are "like works of art" Meyer said. It's rumored that the most expensive cowrie ever sold for more than $50,000. The NMNH collection, which contains some 50,000 specimens, is likely worth millions (though the Smithsonian would tell you that its collections are "invaluable.")
Then there's cowries' scientific value.
The Cypraeidae family includes more than 200 living species of cowrie and extends back to the age of the dinosaurs. The animals themselves are sea snails: small and slimy, with flaps of flesh that extend out over the shell to enclose it like a jacket. These flaps of skin secrete the pigments that create the characteristic complex designs on the shell's surface.
Cowries hide in caves and under rocks during the day and come alive at night, when they feed on corals and algae and are fed on by crabs and octopuses. The animals can be used as bellwethers of coral reef diversity, and their shells make extraordinarily good fossils, so they can be studied to understand ancient reefs.
"They're really useful as a model," said Meyer, whose research is focused on why cowries diversify into new species and what makes them go extinct.