Biche-de-Mer

While reading Edgar Allan Poe’s rather remarkable short novel, The Narrative of Arthur Gordon Pym of Nantucket (1838), I was struck by a bit of natural history involving a sea creature called “biche-de-mer.”

At this point in the narrative, Pym has become a crewman on a British sailing schooner called the Jane Guy, bound for the South Seas on a trading and sealing mission.

The captain decides to explore south of the Antarctic Circle, and they discover a strange island inhabited by a dark-skinned race. They decide to work with the islanders to harvest biche-de-mer from the shallow coastal waters, for eventual sale to the Chinese and others.

About six years before Poe’s novel appeared, American sea captain Benjamin Morrell had published an ostensibly true account of his nautical adventures entitled Narrative of Four Voyages (1832) in which he talks about the biche-de-mer. Morrell describes the creature as “an edible sea-slug” much in demand by the Chinese:

"Some of them are as much as a foot and a half long. The Chinese eat them, and think them a great luxury" (p97)

Poe is said to have borrowed extensively from Morrell’s account, though changing things significantly to suit his purposes.

Here is some of what Arthur Gordon Pym says about the biche-de-mer:

This mollusca is oblong, and of different sizes, from three to eighteen inches in length; and I have seen a few that were not less than two feet long. They are nearly round, a little flattish on one side, which lies next the ground, or bottom of the sea; and they are from one inch to eight inches thick. They crawl up into shallow water at particular seasons of the year, probably for the purpose of gendering, as we often find them in pairs. It is when the sun has the most power upon the water, rendering it tepid, that they approach the shore; and often into places so shallow, that on the tide's receding they are left dry on the coral reef, exposed to the heat of the sun. But they do not bring forth their young in shallow water, as we never see any of their progeny; and the full-grown ones are always seen coming in from deep water.  They feed principally on that class of zoophytes which produce the coral. 

 The biche-de-mer is generally taken in three or four feet water; after which they are taken to the shore, where they are split at one end with a knife, the incision being one inch or more, according to the size of the mollusca. Through this opening the entrails are forced out by pressure, and they are much like those of any other small tenant of the deep. The article is then washed, and afterward boiled to a certain degree, which must not be too much nor too little. They are then buried in the ground for four hours; then boiled again for a short time, after which they are dried, either by the fire or the sun. Those cured by the sun are worth the most; but where one picul (133 1/3lb.) can be cured that way, I can cure thirty picul by the fire. When once properly cured, they can be kept, in a dry place, for two or three years, without any risk; but they should be examined once every few months, say four times a year, to see if any dampness is likely to affect them. A picul, according to the Chinese weight, is 133 1/3, lb. avoirdupois. 

 The Chinese, as before stated, consider biche-de-mer a very great luxury; believing that it wonderfully strengthens and nourishes the system, and renews the exhausted vigour of the immoderate voluptuary. The first quality commands a high price in Canton, being worth ninety dollars a picul….

The creature Pym is describing is of course the sea cucumber, which was often called the “sea slug” in the 18^th and early 19^th centuries.

As our friends at Wikipedia tell us:

Sea cucumbers are echinoderms from the class Holothuroidea. They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothurian species worldwide is about 1250 with the greatest number being in the Asia Pacific region. Many of these are gathered for human consumption and some species are cultivated in aquaculture systems. The harvested product is variously referred to as trepang, bêche-de-mer or balate. Sea cucumbers serve a useful purpose in the marine ecosystem as they help recycle nutrients, breaking down detritus and other organic matter after which bacteria can continue the degradation process….  

 In recent years, the sea cucumber industry in Alaska has increased due to increased export of the skins and muscles to China. 

 In China, sea cucumbers are farmed commercially in artificial ponds. These ponds can be as large as 1,000 acres (400 ha), and satisfy much of the local demand. Wild sea cucumbers are caught by divers and these wild Alaskan sea cucumbers have higher nutritional value and are larger than farmed Chinese sea cucumbers. Larger size and higher nutritional value has allowed the Alaskan fisheries to continue to compete for market share, despite the increase in local, Chinese sea cucumber farming.

Interestingly, a controversy has developed in Canada over a plan to begin sea cucumber farming in Baynes Sound, between Denman and Vancouver Islands on the Pacific coast. Baynes Sound is a popular recreation area, and local residents are worried that sea cucumber farming will lead to industrialization of the area.

Says one press account dated June 1:

A proposed underwater sea cucumber farm that will stretch for five kilometers along the shore of Baynes Sound has opponents raising the alarm and mobilizing to stop the application before it is approved, but they have only one month to do so…. 

 If tenure is granted, it means the applicants Dan Bowen and Eric Gant will be past the first and arguably biggest hurdle in gaining a license to seed and harvest the sea creatures, considered a delicacy in parts of Asia, for the next 10-30 years…. 

 Bowen said that the cultivation of sea cucumbers, which live in the permanently submerged subtidal zone, will not impact residents or recreational users. The animals grow below the surface, somewhere between two to 20 metres under water, and they are seeded and harvested by divers. During their first few months after seeding, divers, working from a 32-foot boat, will check on the sea cucumbers every couple of weeks. After that, they will return approximately once a month until the animals are harvested when they are two to three years old.

What do sea cucumbers taste like? One blogger reports:

Sea cucumber is like a ghost. It seems substantial but after a few bites it just disappears and gives very little in flavor and leaves even less in aftertaste. It’s as if you never ate anything, like el Bulli foam.

There you go.

When Giant Funguses Ruled the Earth

About 400 million years ago, during the Devonian period, the world was a very strange place.

Green plant life had begun to cover the land surfaces of the Earth, but these plants were small, most of them ferns, and they only grew a foot or two high at most. This was long before the age of the dinosaurs, and there were no animals with backbones anywhere on land.

In this placid setting, there arose a form of life that was stunning in its size and bizarre in its appearance. For more than a century, scientists have puzzled over its fossils, trying to figure out exactly what it was.

The fossils are large mineralized columns, like tree trunks, sometimes reaching eight or more meters (24 feet plus) in length. They have been found scattered around the globe, in places like Canada, Australia and Saudi Arabia.

At first these life forms were thought to be trees – conifers. Their name, Prototaxites (pronounced “pro-toe-tax-eye-tease”) means “early yew tree.” But they had no branches. They were eventually determined not to be “vascular plants,” the term used for higher plants with conducting tissues that allow resources like water, minerals and photosynthesis products to circulate throughout the organism. Later theories characterized Prototaxites as a lichen, or perhaps algae, or fungus.

In 2007, scientists from the University of Chicago and the Smithsonian’s National Museum of Natural History in Washington, D.C., announced they had finally solved the mystery of “one of the weirdest organisms that ever lived”: Prototaxites was indeed a fungus – a giant, tree-trunk-like fungus.

The fungus theory had first been advanced in 1915 and was revived in 2001 by Francis Hueber of the Smithsonian. Hueber’s research has played a large part in the latest determination. The Chicago and Smithsonian researchers found independent evidence supporting Hueber’s contention that the life form was a fungus:

The team did so by analyzing two varieties—isotopes—of carbon contained in Prototaxites and the plants that lived in the same environment approximately 400 million years ago. The metabolism of plants is limited by photosynthesis. Deriving their energy from the sun and their carbon from carbon dioxide in the air, any given type of plant will typically contain a similar ratio of carbon-12 to carbon-13 as another plant of the same type. “But if you’re an animal, you will look like whatever you eat,” [Chicago’s C. Kevin] Boyce said. And Prototaxites displayed a much wider variation in its ratio of carbon-12 to carbon-13 content than would be expected in any plant. Geological processes can alter the isotopic composition of fossils, but Boyce and his colleagues conducted tests to verify that the carbon isotopic composition of the specimens they analyzed stemmed from organic rather than geologic factors. As for why these bizarre organisms grew so large, “I’ve wondered whether it enabled Prototaxites to distribute its spores widely, allowing it to occupy suitable marshy habitats that may have been patchily distributed on the landscape,” [the Smithsonian’s Carol] Hotton said. The relatively simple Devonian ecosystems certainly seemed to contain nothing to prevent them from growing slowly for a long time. Plant-eating animals had not yet evolved, Boyce said. But even if Prototaxites hadn’t been eaten by the dinosaurs and elephants that came much later, they probably grew too slowly to rebuild from regular disturbances of any kind, Boyce said. “It’s hard to imagine these things surviving in the modern world,” he said. 

So it’s official: The Devonian was the period when giant funguses ruled the Earth.

But wait a minute – someone has come up with another theory challenging the experts.

In 2010, Linda E. Graham of the University of Wisconsin and several colleagues published a paper presenting evidence that the tree-trunk-style fossils of Prototaxites were not towering columns of fungus after all, but rather rolled-up liverwort mats (similar to rolls of grass sod).

As a recent “Catalogue of Organisms” blog post describes the new theory:

In Graham et al.'s estimation, Prototaxites should not be classed with the fungi but with the liverworts. Liverworts are small, often mosslike plants of moist habitats. Members of one group of liverworts, the thallose liverworts, lack any distinction between leaves and stem but grow as a flattened thallus anchored to the ground by rhizoids (rootlets) on the lower surface…. But modern liverworts lack strong supporting tissue and would be pushing to reach an inch in height - how could they have produced the eight-metre columns recorded for Prototaxites? A transverse section of Prototaxites shows a ring structure like that found in a tree trunk. Hueber (2001), who interpreted Prototaxites as a perennial fungal fruiting body, felt that this ring structure also resembled tree rings in indicating discontinuous growth by the organism. Graham et al. (2010) interpret the ring structure differently. They suggest that large mats of thallose liverworts covered the Silurian landscape. These mats could become detached from their substrate by agents such as wind and rain, and start to roll up as they decayed. As they rolled, they would form the large columns that, after being compressed by burial and fossilised, would eventually be identified as Prototaxites.

The blog author, an entomologist, finds this new interpretation “intriguing, if a little difficult to accept outright.”

He adds:

Prototaxites is represented by a reasonable number of specimens (I don't know the actual number, but thirteen species have been named from numerous localities around the world) - were the conditions that would have lead to mat-rolling common enough to have produced that number of fossils? I wonder if it would be worth investigating how Prototaxites specimens compare in abundance to nematophyte specimens and what that might tell us about the likelihood of 'Prototaxites' formation from liverwort mats. Certainly, the only thing that could be more intriguing than the existence of these giant pillars from so early in the earth's history would be if it turned out that they never existed at all.

On a personal note, I’ve inspected large Prototaxites fossils recovered by Saudi Aramco geologists from an area in central Saudi Arabia. They do indeed resemble tree trunks, and one can easily imagine them standing tall, some 400 million years ago, in the region today called Najd, swaying slightly in the wind, dominating the ferny landscape for miles around.

It is much less easy to imagine them as the fossilized equivalent of fruit rollups….