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Ferrebeekeeper has presented catfish which live beneath the water table, chickens which look like they have no head, 600 pound turtles, clams which have been alive since the 17th century, and turkeys which give virgin birth…not to mention the “King of Herring” the world’s longest bony fish. We are no strangers to strange creatures! But today we come face to face (?) with what might be the strangest creature of them all! Steel yourselves for a creature which is literally made of metal! [crazy metal guitar solo]

And here it is! Behold the scaly foot gastopod (Chrysomallon squamiferum) a tiny snail [5 cm] which lives in the Indian Ocean!

Um, maybe I need to add some context to help explain why this small drab mollusk is so exceedingly strange. First of all, the scaly foot snail is a creature of the deeps: the snails live on (in? around?) deep sea ocean vents which are at least 2,400 meters beneath the ocean surface. Specimens have been discovered as deep as 2,900 meters below sea level. In British Imperial measurement that is 1.5 to 2 miles underwater! And these snails live on/in/around hydrothermal vents where water temperature can reach 400° Celsius (about 750° Fahrenheit) and where oxygen is scarce and yet hydrogen sulfide is abundant. In case all of this was not unusual enough for you, the snails are all simultaneous hermaphrodites (meaning they have complete functioning sets of reproductive organs of both genders and frequently self-fertilize).

Yet the strangest thing about the scaly foot snail is what it eats: nothing! Or to be more specific the adult creatures are obligate symbiotrophs–the snails live on the secretions of gammaproteobacteria which live within their oesophageal glands. The bacteria are extremophiles which metabolize the chemical rich waters of the vents. These snails do not live directly or indirectly from photosynthesis!

The snail’s signature feature may be its armor. The shell is a three level composite of iron sulfide on the outside, protein in the middle, and calcium carbonate on the inside. Like wise the snails’ sensitive feet are covered in composite nodules of iron sulfide and protein. All of this armor keeps the little snails safe from the predators of the vent ecosystem–strange crustaceans which look like furry white lobsters and larger predatory snails. I wrote briefly about this snail about a decade ago, when I concentrated more on the uniqueness of its armor. Back in those days we thought that nothing could possibly harm the scaly-foot snail, a creature which I imagined to be perfectly safe in its own little alien world at the bottom of the ocean (except for occasional predation by those larger snail, of course). But Earth’s greediest animal has a habit of getting everywhere and lately the scaly foot snail has been endangered by deep sea mining operations which aim to harvest the rare and valuable minerals around deep sea vents. It is hard to believe that our arms have grown long enough to harass these poor little weirdos in their little suits of armor a mile and a half beneath the waves, but, frankly I may have misspoke about which animal is really the weirdest


Today we have a special mystery:  a strange sacred underground passage of great beauty which was constructed by unknown entities for unknown reasons.  Shell Grotto in Margate Kent is an underground passage constructed entirely of seashells (or, I should say, the walls and ceilings are entirely lined with shells).  The passage is 2.4 meters (8 feet) high and 21 meters in length (69 feet) and terminates in a 5 x 6 meter (16 foot by 20 foot) chamber colloquially known as “The Altar Room.”  The entire complex is hewn out of the native chalk of Kent and extensively decorated with vaults and decorative mosaics made of local mussels, cockles, whelks, limpets, scallops, and oysters (although winkles from as far away as Southampton.


The complex was “discovered” in 1835 and has been the subject of much speculation ever since.   Some people assert that it was a prehistoric astronomical calendar (?), a special space for Templar or Freemasonry ceremonies, or an 18th century nobleman’s folly.  The first mention of it in the press is from 1838, announcing its forthcoming opening as a public attraction.  My own hypothesis is that the grotto is a Victorian attraction.


Originally the shells had their vibrant natural colors, but after long exposure to flickering Victorian gaslights they had blackened and faded.  Fortunately, Shell Grotto is protected as a Grade I listed building of special historical and cultural interest (although no archaeologists seem particularly interested, which reinforces my “Victorian tourist trap: hypothesis).  Whatever its provenance, Shell Grotto is certainly impressive.  It is estimated that the builders, whoever they were, employed about 4.7 million shells to make the complex.  Their initiative and hard work have paid off: Shell Grotto has a mysterious oceanic splendor and beauty all its own.  The enigma of its nature only adds to its picturesque (but haunting) charm.

A Giant Triton (Charonia tritonis) on an Indonesian Reef

A Giant Triton (Charonia tritonis) on an Indonesian Reef

Yesterday this blog took us to the depths of space to explore the frozen ice-moon of Triton.  Today we atone for that cold voyage with a trip to the inviting tropical seas of the Indo-Pacific.  In these vibrant waters can be found one of the greatest living gastropods, a prince among predatory sea snails, the mighty Charonia tritonis, (commonly known as the giant triton or Triton’s trumpet).

A Giant Triton climbs over a pillow coral in Hawaii

A Giant Triton climbs over a pillow coral in Hawaii

Charonia tritonis grows to over half a meter (20 inches) in length: it is one of the largest living snails in the world (and it is not much smaller than the biggest extant snails). Equipped with a powerful muscular foot, acute senses (particularly smell), and an agile tentacle-like proboscis, the snails are formidable hunters.  Additionally they are protected from predators—even big fierce ones–by their beautiful spiral shells which are vibrantly colored orange, brown, yellow, and cream.  Of course such a shell would become a liability for the snail if an animal ever evolved which killed the snails in order to harvest the magnificent shells solely for their beauty (but what are the chances of that?).

A man sounds a blast on a triton shell--which has spiritual significance in Hawaii

A man sounds a blast on a triton shell–which has spiritual significance in Hawaii

Giant tritons hunt at night.  Their main prey are echinoderms—starfish, which can be large powerful and armored.  Fortunately the snails are not just equipped with powerful muscles and superior brains.  They also have salivary glands that produce sulfuric acid AND a chemical which paralyzes starfish.  The tritons find starfish—even big spiny poisonous starfish like the invasive and all-consuming crown-of-thorns which bedevils the reefs of the Indo-Pacific—then hold them down and inject saliva into them.  As the starfish dissolves from within, the snails rip them apart and feast!

A triton kills a crown of thorns

A triton kills a crown of thorns

Tritons have a specific gender—they are male or female.  They seek each other out for courtship and the female then lays a large clutch of eggs.  When the eggs hatch, the young snails become part of the oceanic plankton for a (poorly understood) time before developing into adults.  Triton shells are esteemed by many cultures as sacred musical instruments.  The shells themselves are collector’s items and are arguably better known then the formidable long-lived predators which make them.  Although the snails are not threatened with extinction as such, there are fewer and fewer really big adult ones (or even small ones) on today’s reefs. This is a real shame, since those same reefs are being devoured by the horrible crown-of-thorns. Hopefully a new generation of divers and wildlife enthusiasts will appreciate the triton on the reef and leave them to their invaluable hunting.  Resist the urge to buy the beautiful shells and help save the reefs of the Indo Pacific!


Double-headed Serpent Carving (Aztec, ca. 1500 AD, wood, turquoise, spondylus, and conch)

Double-headed Serpent Carving (Aztec, ca. 1500 AD, wood, turquoise, spondylus, and conch)

In Aztec mythology, snakes are symbolic of rebirth and renewal. Since serpents regularly shed their skins and emerge shining and fresh as though made anew, they seemed to Aztec mystics to transcend the dull cycle of aging. Likewise snakes’ ability to hide in the earth, swim in water, and climb high into the rainforest canopy made them a symbol of transcending physical boundaries: snakes were seen as liaisons of the gods capable of traveling through heaven, earth, and the underworld.  In fact many of the most important Aztec gods were snakes like Xiuhcoatl (the fire serpent), Mixcoatl (the cloud serpent), and Quetzalcoatl himself (the feathered serpent who acts as chief of the gods).

Here then, as a final post of 2013 and a first post of 2014, is an exquisite Aztec artifact:  a double-headed wooden serpent inset with a mosaic of turquoise, spondylus (thorny oyster), and conch shell.  Once upon a time the ornament had eyes (possibly of gold or pyrite which were affixed to the wooden serpent with gluey beeswax) but they disappeared at some point in the five hundred years since the object was made—and their absence might make for a stronger piece. The serpent was probably worn as a pectoral (the opposite side is unadorned and hollow).  It is made from wood from the Spanish cedar (Cedrela odorata) a tree with natural termite resistance long-used to make boxes, musical instruments, furniture, and fine carvings (obviously).



Really look at the carving for a moment, it was a sacred treasure of a mighty vanished civilization. It represents the nature of time: mighty and ferocious with unknowable divine attributes, but also regular and cyclical (and beautiful).  The double-headed serpent has no beginning or end. Like an ouroboros, or a figure-eight, it is a symbol of infinity—of time closing in on itself in an unending circle.

The Aztecs of course ended: their realm blew apart in fire, bloodshed, and smallpox.  Their greatest treasures were melted down for inbred Spaniards to wear as chains…or hung up on a wall at the British museum.   But of course the Aztecs are not really gone.  Their descendants are everywhere and their customs live on.  Likewise the living spondylus shell in the ocean is the descendant of countless millions of generations of evolving mollusks—changing color, shape, and temperament over the long eons.

I chose to highlight this this simple object because it unites so many of the topics on this site: snakes, color, art, trees, history, mollusks, bees (because of the wax), the underworld, and the heavens.  The double-headed snake represents the way in which many different ideas are enmeshed with each other and flow together, even as time relentlessly pushes us all onward.  Isn’t that what life is?

Best wishes for a very happy new year and, as always thank you for reading!



A Black Smoker Geothermal Vent

A Black Smoker Geothermal Vent

The African Plate and the Indo-Australian Plate meet together deep beneath the surface of the Indian Ocean in a long line of tectonic divergence known as the Central Indian Ridge (CIR).  As new seafloor is created hydrothermal vents pour out molten hot fluids rich with minerals and an alien landscape is formed.  The hot minerals precipitate to form high cylindrical chimneys called smokers and strange communities of life form along these structures.  This ecosystem is entirely based upon chemosynthetic archaea (ancient one-celled life forms which take energy directly from the oxidation of inorganic compounds).  Great communities of eyeless shrimp, giant tubeworms, and annelids support themselves on the archaea.  Among the strange creatures is a very weird gastropod mollusk, the scaly-foot snail (Crysomallon squamiferum), which is different from every other mollusk (and indeed every other animal) because of the material it uses for its bizarre scale-mail armor.

The Scaly Foot Gastropod (Crysomallon squamiferum)

The Scaly Foot Gastropod (Crysomallon squamiferum)

The scaly foot gastropod has an armored foot which is covered in little scales made of iron sulfides.  Additionally the deep-sea snail has a triple layer shell.  The outermost shell layer is composed of iron sulfides, the middle is a thick protein coat, and the inner shell layer is composed of aragonite (a calcium carbonate).

I wish I could tell you more about the habits of this snail but since it is found in super heated water at the bottom of the Indian Ocean, it has not been extensively studied.  However, The US military is interested in the creature as a possible inspiration for next generation composite military armor so maybe we will all learn more about the scaly foot snail.

Detail of the Foot Armor of Crysomallon squamiferum

Detail of the Foot Armor of Crysomallon squamiferum

Marbled cone snail (Conus marmoreus) by shadowshador

In olden days, in Australia, young healthy beachgoers were sometimes found lying on the shore dead.  Their bodies gave no evidence of trauma, indeed they had not even gone into the water. Something just struck them down as they sauntered along the beach.  It was not until 1936 that the mysterious killer was finally revealed when a beachcomber picked up a colorful snail and began to scrape its shell with his knife.  The unlucky young man uttered a cry as the snail somehow pricked him.  He then fell down, went into a coma, and shortly died.  Because of witness testimony, coroners knew what to look for and they removed a tiny poisonous harpoon the size of a small hair from the victim’s hand. The culprit turned out to be a cone snail, one of a diverse group of deadly gastropod mollusks.

The Geographic Cone Snail (Conus geographus) shows its siphon and proboscis. This snail is also humorously called “the cigarette snail” since if one stings you, you allegedly have time for one cigarette before dying.

There are over 600 different species of snail within the genus Conus and they are all poisonous predatory hunters.  The smaller cone snails hunt tiny mollusks and worms but the larger snails feed on fish, which need to be quickly subdued (so that they do not injure the snail by thrashing about) and then consumed with equal dispatch so that other ocean creatures do not steal the meal.  In order to quickly dispatch their prey (and defend against larger predators), Cone snails have a sophisticated weapon–a modified radula tooth which directly injects potent venom by means of a tiny harpoon-like “dart.”  The snail finds prey by carefully testing/sniffing the water with a siphon.  It then stretches out a long flexible proboscis and fires the disposable hollow radula tooth (filled with venom) into the prey by means of a powerful muscle contraction.  Below is a shocking film which shows a cone snail killing and consuming a clown fish by such means.  It is not for the faint of heart!

Although cone snails are obviously alarming to divers and shell collectors (particularly in warm tropical reefs where the large poisonous specimens live), the potent cocktail of neurotoxins utilized by the creatures is of great interest to pharmaceutical researchers.  Since each species of cone snail has a very large number of different “conotoxins” in its poison, scientists have been struggling to catalog and understand the dangerous mixtures. These conotoxins are generally peptides which interfere with the ability of nerve cells to communicate with one another.  Not only might such chemicals provide the key to curing neurodegenerative diseases and brain cancers,  conotoxin research is now the most promising avenue towards effective medications to deal with certain sorts of chronic pain.

A lovely diagram of Conotoxin Peptides from “The Journal of Neuroscience”

Unfortunately all of this research has not provided any effective antitoxins for victims of cone snail stings.  If a person is fully darted by one of the large poisonous specimens, their best hope is to go on a ventilator until their body expunges all of the poison—an uncertain prospect at best.

A Tiny Sample of the Exquisite Variety of Cone Snail Shells (Photo by Pet/Wikimedia Commons)

Many cone snails have beautiful colorful shells marked with vivid abstract patterns.  Some of the most valuable shells ever came from cone snails–which continue to fascinate conchologists and shell collectors.  Even today divers and beach combers are sometimes overwhelmed by the beauty of cone snails and reach out to grab the lovely creatures.  Hopefully this article has convinced you that doing so is a very bad idea.

Ah Florida…sultry weather, orange groves, glistening beaches, pouting beauties, and palm trees…but also walking catfish, killer snakes, and now giant mollusks!  The semi-tropical peninsula is prey to wave after wave of exotic animal invaders.  The most-recent problem creatures are giant African snails, immense land snails that can grow up to 20 centimeters (8 inches) long. There are three extremely similar species of giant snails which come from West Africa: the giant African snail (Achatina fulica), the giant Ghana tiger snail (Achatina achatina), and the margies (Archachatina marginata).  Each snail has a brown swirly shell and grows to be about the size of an adult’s fist.

Archachatina marginata

The giant snails eat over 500 varieties of plants—including the majority of agricultural and ornamental species.  They also have a taste for stucco and siding so some Floridians now awaken to discover that huge mollusks are literally devouring their houses.  The snails are hermaphrodites and can lay up to 12000 eggs per year.  They can survive freezing temperatures.

Authorities continue to investigate how the snails got into the country but increasingly the evidence points to…voodoo.

In the Yoruba creation myth, the entire world was once water.  The god Obatala possessed a magic snail shell which contained earth. Acting on instructions from the supreme divinity Olódùmarè, Obatala cast this land upon the oceans, thus creating the continents.  Obatala then molded the land into men and beasts–but he possessed an artist’s temperament and thirst. As he crafted the Earth and its inhabitants he drank so much palm wine that his mental clarity became dulled and he made big parts of existence wrong.  Eventually he passed out altogether and his brother Oduduwa was left to finish the work and patch up the errors as best as he could.  Unfortunately big parts of humanity were assembled incorrectly and these flaws remain in evidence everywhere…


Anyway a mainstay of Obatala worship is the sacrifice of snails (in memory of the primordial snail shell which contained the first earth).  Apparently one of Obatala’s worshippers illegally brought some giant African snails into Florida for religious reasons and they escaped from him.

So, to recap, a smuggler who worships a drunken deity brought giant hermaphrodite snails in to Florida as a religious devotion to his addled god.  Unfortunately the snails escaped and they are now eating people’s homes. Argh! What is wrong with us?  I’m going to go drink some palm wine…

Next time please just light a votive candle!

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)

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April 2021