To the deceptively simple lessons of nature, humankind has turned repeatedly for renewal, self discovery, and a glimpse of their place in the great nature of things. Few creations of the natural world have served so well and widely in this quest as the lowly mollusk. Hunted from the beginning for its succulent flesh, its castoff shell has been a part of the human landscape ever since humans, perhaps as remote descendants of the sea, began to set their mark upon the earth.
Such is the charisma of the shell that it has been more avidly sought, collected, exchanged, worn and even worshipped than almost any other natural object. It has inspired ancient metaphors of birth, death and divinity that, immortalized in the art and literature of centuries, are still vital. This is perhaps because we recognize in its myriad forms what the poet Paul Valery has called, ”the ideas of order and of fantasy, of invention and of necessity, of law and exception.” But it is modern biology, by making us aware of the essential connectedness of art and science, that has given conchology its most fascinating interest.
Shell collecting for its own sake first appeared in England and the Low Countries early in the seventeenth century, coinciding with the dawn of the scientific revolution. Sailors returning from long voyages of exploration and trade in Africa, the Americas and the Pacific brought back sea chests full of exotic specimens and found a ready market for them. Though most of the new collectors were wealthy dilettantes intent principally on impressing rivals and putting on a handsome show, some became patrons of genuine naturalists and thus a beginning was made in the systematic study of life beneath the sea.
Two centuries later, Edgar Allen Poe described this inflated passion for collecting in a modest little work prepared for schoolroom consumption entitled, ”The Conchologist’s First Book” . Regarding conchology, he stated, ” there have been men of all ages who have carried to an absurd, and even pernicious extreme, pursuits the most ennobling and praiseworthy.”
Among the most adaptable creatures in the animal kingdom, mollusks absorb almost any change in their environment with equanimity, though their offspring may take on a subtle new look in the process. They owe this remarkable talent to the mantle, a secretory organ which creates the shell from the lime and other mineral salts in the water, and to the specialized pigment producing cells that weave their unique markings. A change in the chemistry or temperature of he water, in food supply, in predators, even the arrival of a genetic freak among their numbers, may in the short span of a few generations produce still another species better adapted to its new surroundings.
Their characteristic spiral has been the wonder and inspiration of artists almost as far back as formal design can be traced; and indeed, seen in cross section, the curved inner structure of a snail suggests the hand of as fine a draftsman as Leonardo Da Vinci. He did in fact make studies of several species, and the graceful proportions he discovered are thought to have guided another architect in designing the monumental staircase of the chateau at Blois. Albrecht Durer, too, made geometric sections based on the ”line of the shell” for his treatise on proportion, decades before mathematicians began to study logarithmic curves. In the twentieth century Frank Lloyd Wright found his inspiration for the helicoid shape of New York’s Guggenheim Museum in the architecture of snails.
There is evidence that snails have also suggested forms found in ancient Mayan and Aztec
itecture. The Greeks were sufficiently impressed with the beauty of the shell to reproduce one species’ whorls in the Ionic capitals of their temples. To make the transfer from nature to art complete, craftsmen may have wound a string around an actual whelk shell and used it as a rudimentary compass to inscribe the expanding spiral on a stone.
The fierce looking, spiny shelled Murex was the principle source of purple dyes from Babylonian times on. As early as 1500 B.C. it had been a major factor in providing Pheoninicia, whose Greek name is a derivative of ”red”, with wealth and a colonial empire that spanned the Mediterranean. So valuable were the dyes extracted from a small gland within the animal that the wearing of purple was reserved for the high born, a tradition honored to this day in the royal robes of the great European dynasties and in the vestments of the Roman Catholic Church.
The second class of mollusks are the bivalves. Their shared characteristic is a two-part shell held together by a variety of ingenious hinges. In their sex life, clams show little more stability than the scandalous snails, changing from male to female at different stages of life and even living dexterously as hermaphrodites. Once again, it was the Greeks who gave the bivalve the symbolism by which it has been immortalized in the myth of Aphrodite rising from the foam on a scallop shell. The scallop was probably never more extravagantly used and more variously rendered as ornament than in the rococo style of the eighteenth century.