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For Saint Valentine’s Day here is a collection of “sailor’s valentines”.  These were ostensibly a form of nautical art—like scrimshaw–created by old sea dogs in the days of canvas and manilla.  On the long voyages the grizzled sailors would tenderly glue shells together in wooden (particularly octagonal cases) to give to their family and sweethearts when they returned to port.  There is something appealing about this picture–but seashells come from shore.  Additionally one wonders how much craft space sailors were allowed in the age of wind.

A counter narrative has arisen that sailors would buy these shell designs from a merchant in Barbados who was responsible for most of the early examples.  Once the idea became popular, artisans began to make the little seashell mosaics at home. To be honest, I can picture my great-grandmother at a table filled with shells and glue much more easily than I can sea Captain Haddock putting together something like this. Whatever the case, the carefully arranged shells create delicate and lovely little artworks.  Even if they were not made by sailors or given at Valentine’s Day, I am repurposing them as a valentine to all of my readers!

To reiterate: Happy Valentine’s Day!

Last night my roommate told me about bitcoins, a digital currency created two years ago by Satoshi Nakamoto, a shadowy entity who may be a financier, a programmer, or an anarchist (or he/she/it may not even be a person at all).  The name “bitcoins” also refers to the software and built-in encryption features which allow the “coins” to be anonymously transferred while still retaining whatever “realness” they have.  The concept initially filled me with unreasoning anger, but thinking about bitcoins has caused me to reflect more deeply on the notional nature of all money.  Most dollars are no more real than bitcoins: only a tiny fraction of American legal tender exists in the real world (as the paper scraps or metal disks found in cash registers, laundry machines, money clips, dancers’ garters, underground hoards, piggy banks and what have you).  The majority of money is ones and zeros zipping through huge servers run by large financial institutions–not really that different from bitcoins (although the dollar is backed by lots of important guys in suits and by a huge military rather than by the personal assurances of a Japanese cyberpunk shadowspawn).

Stone Money of Yap

Instead of thinking about today’s national currencies I like to reflect on currencies based on real objects but still not pegged to any use value.  The rather beautiful giant stone coins of Yap are probably the most well-known example of such money, however, a more interesting and widespread example is provided by mollusk shells–which have been used as a medium of exchange by different societies worldwide throughout history.  Over three thousand years ago the Chinese were using cowry shells as currency. It is said that the classical Chinese character for money was the same as for cowry (I am going to leave Chinese scholars to argue over the actual characters—trying to follow the vagaries of Chinese etymology left my head spinning).  In Thailand the “bia” was a unit worth 1⁄6400 Baht and was literally a cowry (which was also a common counter used in gambling).  On the East Cost of the United States, Iroquois and Algonquian tribesmen utilized “wampum” belts manufactured from littleneck clams to solidify treaties or as exchange for personal transactions.  Tribes of the Pacific Northwest utilized tusk shells or scaphopods for their shell money.  Different tribes of Australian aboriginal people utilized different shells as money and often regarded the money shells from other tribes as worthless.  Other examples of shell currency are numerous and come from all parts of the world, but one is particularly instructive.

A living Being--the Egg Cowry (Calpurnus verrucosus)

The most infamous use of shell currency may also have been the most complicated and lucrative. In the seventeenth, eighteenth, and early nineteenth centuries competing Dutch, Portuguese, English, and French slave traders utilized cowry shells as a common medium of exchange (among several others) to buy slaves along the African coast.  The slaves were sold by local rulers who obtained them in internecine tribal wars or by Arab merchants who specialized in mass kidnappings. The cowrie shells used in such transactions originated from the Maldives and later from Zanzibar.  They were carried to the Mediterranean and to the Sahara by Arab traders and to Europe by merchants from the miscellaneous colonial powers. The potential “mark-up” on such shells was tremendous since one could obtain then easily from living snails in the Indian Ocean and then exchange them for living people in the Bight of Benin.

Cowry Shells being used as Money by an Arab Trader ( Benjamin Waterhouse Hawkins, 1845, print)

My personal feelings about international trade are not as negative as this grim historical example would seem to indicate (I feel that today global trade is, on balance, more likely to deliver people from slavery than into it). However I feel that this example is a good metaphor for the central mystery of money.  Cowry shells are pretty and have been used for rituals, games, and adornments for a long time–but their value does not seem intrinsic in any special way–except maybe to living cowries.  Indeed the monetized mystique such shells had in the eighteenth century is long gone: I found many web sites which will sell you barrels of money cowrie shells for next to nothing. What is the magic that makes shells worth a human life in one era and a quasi-worthless novelty in another?  I have no answer other than to point at the strange epic that is history.  I suspect that the smug Federal Reserve Board members discontentedly shaking their heads at the tone of this article do not have one either.  Money is a fairly obvious illusion…and yet you will never live your life outside its thrall.

Money Cowry Shells (Shells of Monetaria moneta)

A diorama portraying the seas of the Ordovician Period (from the Exhibit Museum, University of Michigan)

The Ordovician Period, the second period of the Paleozoic Era, took place from 488 to 444 million years ago.  During those 44 million years, the landmasses of earth were devoid of life except for hardy lichens, tiny algae, and a few lowly non-vascular plants. The oceans, however, teemed with diverse marine invertebrates and primitive vertebrates.  The ecosystems of these great shallow seas seem familiar–with colorful intermeshed filter feeders, grazing herbivores, and swift deadly predators. And yet the creatures are so alien as to make Ordovician reconstructions almost resemble another planet.  All of the creatures of a modern coral reef are replaced by strange analogs:  the dominant filter feeder were not corals but weird sponge-like animals—the archaeocyathids.  The grazers were conodonts and trilobites.  The predators were primitive sharks, huge scorpion-like eurypterids, and above all, the nautiloids–for the Ordovician was a time when cephalopods ruled the earth.

Clever mollusks with multiple tentacles, eyes, and a method of jet propulsion, cephalopods had evolved in the Late Cambrian from a snail-like ancestor.  Their taxonomy exploded in complexity during the Ordovician period.  They also left the shallow continental shelves to range across the pelagic ocean and to descend into the benthic depths.  The cephalopods of the Ordovician period were the nautiloids, animals which manipulated a bubble of air within a chambered shell to move up and down the water column.  They could grab prey with their many tentacles or retreat into their calcium-based shell. The family quickly exploded in complexity. To quote palaeos.com:

At least ten different orders flourished at this time, all but one appearing for the first time during the early or middle part of the Ordovician.  This astonishing diversity included straight, curved, loosely coiled, and tightly coiled shelled types, and even one group (the Ascocerids) that in order to become lighter and more streamlined lost the a large part of their shell altogether.  These intelligent carnivorous molluscs replaced the Cambrian Anomalocarids as the dominant life form and top predator of the world’s ocean.  The biggest, such as the endocerids, attained huge size; with shells of up to 10 meters in length they were the largest animal that, up until that time, had ever lived.

Some paleontologists have expressed doubts about this magnificent ten meter endocerid shell.  But, even so, it is worth remembering that this measurement did not include the tentacles and the head of the creature.  These giant orthocones must have been formidable predators, living on nautiloids, eurypterids, and jawless fish.  The great monsters are believed to have had weak eyes (and could probably be avoided by staying shell-side of the behemoths).  However an even bigger problem faced the tentacled masters of that world.

A giant orthocone

During Ordovician times, the land masses that are now South America, Africa, Madagascar, Antarctica, India, South Asia, and Australia were all joined together as a supercontinent, Gondwanaland.  Over tens of millions of years Gondwanaland gradually drifted into the Southern Polar regions of the globe.  This resulted in heavy glaciation, which in turn caused rapid deep freezes and sudden interglacial warm periods—in other words, an ice age.  This great ice age caused the depth of the ocean to fluctuate wildly which brought a crashing end to the Ordovician and its dominant cephalopods.   The mass extinction which ended the Ordovician period was the second worst in the history of the planet (eclipsed only by the mass extinction at the end of the Permian period).   More than 60% of marine invertebrates went extinct (including whole families of mollusks).   This was but one set back for cephalopods.  The family has burgeoned and then crashed many times, but it marked the end of their time as apex predator.

Various Ordovician cephalopods, including the infamous Cameroceras trentonese, shown feeding on a hapless Aphetoceras americanum, while a quartet of Cyclostomiceras cassinense swim by (illustration by Stanton F. Fink).

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