The Coelacanth

In 1938, thirty two-year-old Marjorie Courtenay Latimer was the curator of a tiny museum in the port town of East London, northeast of Cape Town, South Africa. She had befriended a local seaman, Captain Hendrick Goosen, of the trawler Nerine, which fished the nearby coastal waters of the Indian Ocean. When he put into port the captain made a frequent practice of having the dockman call Miss Latimer to come look over the Nerine's catch. She was welcome to take any unusual specimens she might want for her museum.
On December 23rd, 1938, the Nerine entered port after a stint trawling off the mouth of the nearby Chalumna River. The dockman called Marjorie, who was busy mounting a reptile collection, but felt she ought at least go down to the docks to wish the crew of the Nerine a merry Christmas. She took a taxi, delivered her greetings, and was about to leave when, according to her account, she noticed a blue fin protruding beneath a pile of rays and sharks on the deck. Pushing the overlaying fish aside revealed, as she would later write, "the most beautiful fish I had ever seen, five feet long, and a pale mauve blue with iridescent silver markings." Marjorie had no idea what the fish was, but knew it must go back to the museum at once. At first the taxi driver refused to have the reeking, five-foot fish in his cab, but after a heated discussion, he drove Marjorie and her specimen back to the museum.
Raking through the few reference books on hand, Marjorie found a picture that, she has said, led her to a seemingly impossible conclusion. Her specimen bore similarities to a prehistoric fish, particularly in the structure of the head and the tri-lobed shape of the tail. She made a rather crude sketch of the creature, which she mailed, along with a description, to Professor J.L.B. Smith, a forty one- year-old persnickety chemistry teacher with a locally well known passion for fish, at Rhodes University, Grahamstown, some fifty miles south of East London. Smith, however, was away for Christmas holidays, correcting exams at his seaside getaway. Meanwhile, Courtenay's museum director in East London was not impressed with the find. He dismissed the fish as a common rock cod - a grouper!

But on January 3, 1939, Miss Latimer heard back from Smith in a now famous cable: "MOST IMPORTANT PRESERVE SKELETON AND GILLS = FISH DESCRIBED." However, in an attempt to preserve the fish by mounting it, the innards had been discarded. A search for them in the museum and town trash bins proved fruitless. Even photographs taken of the preparation had somehow been spoiled.
Smith, anxiously biding his time, wondering how he could incorporate the possibility of such a discovery into an already overloaded dual career, did not arrive at the East London museum until February 16. The professor, a thin wiry man of about 5'7", sporting, as was his custom, a close-cropped crew cut, khaki bush shorts and sandals, viewed the mounted specimen, exclaiming, according to one account, "I always knew somewhere or somehow, a primitive fish of this nature would appear." Smith identified the fish immediately as a coelacanth, that is as a member of what must be a still living coelacanth species. The fish would soon be called the "most important zoological find of the century" (an accolade that might now go to the Martian microfossils if they check out.) A living dinosaur, it was said, would be no more amazing than this incredible discovery.
After a local newspaper reporter was allowed to take a single photograph of the mounted coelacanth, the picture soon appeared around the world. Smith, Courtenay-Latimer, and the coelacanth became overnight celebrities. When a public viewing for one day only was arranged, 20,000 visitors are said to have shown up.
But the story of the coelacanth's "discovery" does not end there. With no internal organs left from the East London specimen, many questions remained unanswered. Smith was soon obsessed with finding a second intact specimen. Speculating that the fish had drifted down from the north on the Mozambique current, he had a reward notice with a picture of the first specimen posted among the East African coast up as far as Kenya. A decade went by with no response. Smith continued a long-term project of cataloging the fishes of the Indian Ocean, always proselytizing about the coelacanth wherever he went. It was during this period that the myth of the coelacanth as a deep ocean fish took hold in the popular and scientific imagination. Expeditions from Europe scoured the ocean depths in search of coelacanths. But Smith remained convinced that the fish's physiognomy and blue color made it a lower reef predator and not a true deep-water fish.
Captain Eric Hunt, a dapper thirty eight-year-old Briton who owned and helmed a vessel, the Nduwaro, trading among Zanzibar, Madagascar, and the Comoros, a group of small islands in the Mozambique Channel belonging to France at the time, attended one of Smith's lectures in Zanzibar. An intelligent, curious fellow, with a penchant for marine aquaria, he quickly became fascinated with the whereabouts of the coelacanth. Hunt offered to post Smith's reward notices among the Comoro islands, which are midway between Tanzania and Madagascar. Smith obliged and with the help of local authorities, the Comoros were soon plastered with coelacanth reward notices.
On December 21, 1952, fourteen years after the discovery of the first living coelacanth, Captain Hunt, returning to the port of Mutsamudu on the Comorian island of Anjouan, was approached by two Comorans carrying a hefty bundle. One, Ahamadi Abdallah, had caught by hand-line what the locals called a "mame" or "Gombessa", a heavy grouper-like fish that turned up on their lines from time to time. The fisherman was accompanied by an astute schoolteacher, Affane Mohamed, who had noticed that this was the same fish pictured on the reward notices Hunt had posted. Hunt was ecstatic and arranged for Smith's award of one hundred British pounds to be paid to them. As there was no better preservative available at Mutsamudu, Hunt and his crew salted the fish, then sailed with it to the harbor at Dzaoudzi, an islet off the Comoran island of Mayotte, where he bought formalin from the director of medical services. Already aware of the scientific importance of the internal organs, Hunt injected the preservative into the specimen, then cabled Smith in South Africa. He awaited Smith's response.
The French authorities at nearby Pamanzi were not sure that this creature was indeed the fabled coelacanth. Nevertheless, concerned that they might be missing out on something important, cables were dispatched to French scientific authorities in Madagascar. But no message came back. Hearing nothing, the Pamanzi authorities decided to take possession of the fish anyway if Smith did not come for it personally. Hunt sent a frantic second cable to Smith, urging him to fly to the Comoros immediately.For J.L.B. Smith this find, if indeed it were a coelacanth, would consummate a fourteen-year obsession. Worried all the time that Hunt's specimen might not be what he claimed, Smith negotiated with Prime Minister Malan of South Africa, for a plane to fly him to the Comoros. Malan, out of the capital on yet another Christmas holiday, consented. By now Smith was a nervous wreck, hardly amused when the flight crew of a DC3 "Dakota" put at his disposal for the trip, faked a radio message that French fighters had scrambled to intercept them. Having landed in the Comoros, it was a quick trip from the airstrip down to the harbor at Pamanzi where the Nduwaro was moored. When Smith saw the dead fish he wept. It was indeed a coelacanth. He now had his second specimen, organs intact, and the familiarity of the natives with this creature meant that at least one location of the coelacanth's habitat had been discovered. The Dakota soon left the Comoros with Smith and "his" fish, returning to another round of worldwide publicity.
In the aftermath, the French felt cheated and closed the coelacanth to non-French researchers until the islands became independent in the 1970's. Four years after the "discovery" of the second coelacanth, Eric Hunt disappeared at sea after his schooner ran aground on the reefs of the Geyser Bank between the Comoros and Madagascar. He was never found. J.L.B. Smith wrote his account of the coelacanth story in the book "Old Fourlegs," first published in 1956. His book, Sea Fishes of the Indian Ocean, meticulously illustrated and co-authored by his wife Margaret, remains the standard ichthyological reference for the region. In spite of the controversies that followed, he was content with his role in the fabulous coelacanth episodes. Smith died in 1968. Captain Hendrick Goosen passed away just after the fiftieth anniversary of the "discovery" of the coelacanth in 1988. And Marjorie Courtenay-Latimer was alive and well and still living in East London as of January 2001, the lone survivor of the greatest fish story ever told!

Evolutionary Puzzle

The living coelacanths, Latimeria chalumnae,and Latimeria menadoensis are possibly the sole remaining representatives of a once widespread family of Sarcopterygian (fleshy-finned) coelacanth fishes all but one of which disappeared at the end of the Cretaceous, 65 million years ago. The classification of coelacanths is a murky business with more than one variation in the class category, which will go to far ror here.
The coelacanth appears to be a cousin of Eusthenopteron, the fish credited with growing legs and coming ashore - 360 million years ago - as the ancestor of all tetrapods including ourselves.
But this view is controversial. Debate still rages as to whether the coelacanths, presumed to be close relatives of the Rhipidistia fishes from which tetrapod amphibians supposedly arose, are our closest tetrapod ancestors, or if lung fishes, another very ancient line, are more closely related to tetrapods than the Rhipidistia and thus claim the oldest closest relative title. (There are three living genera of lung fishes.) Good genetic and morphological evidence points in both directions. Another line of thinking, based on physiological and anatomical analysis, identifies coelacanths with sharks and other cartilaginous fishes, but this view seems to have fallen from favor. Today's coelacanths can reach almost six feet (2 meters) in length and weigh up to 150 or more lbs, but they are usually somewhat smaller, particularly the males. They are oportunistic feeders, scarfing up cuttle fishes, squids, and other fishes found in their deep reef and volcanic slope habitats. Coloration is dark blue with distinctive white flecks that can even be used by researchers to designate individuals. (Indonesian coelacanths may be more brown than blue). Scientists believe individual coelacanths may live as long as 60 years. They are ovoviparous, giving birth to as many as 26 live pups which develop from eggs in the oviduct. The coelacanths date back 410 million years to the beginning of the Devonian epoch. One of the incredible aspects of the living coelacanth, Latimeria, is that it offers a genetic and anatomical snapshot of life in those times. The backbone of this fish is composed of a fluid-filled cartilaginous tube, which provides a firm yet flexible support for muscles. Hollow fin spines, identified in fossils, are what got the fish its name- "coelacanth" which literally means 'hollow spine'. The sucking maws of jawless predecessors have transformed, through a modification of one of the gill arches, into hinged, rigid structures with teeth on the bottom ridge and upper palate- true jaws. The tiny brain, is encased in a hardened skull, which hinges in the middle to increase the gape of the mouth while feeding. The eyes are well developed, with reflecting cells called tapita to enhance night vision. A chambered heart pumps blood in prototype to our own. Three indentations on either side of the snout lead to a peculiar cavity, a jelly-filled rostral organ, which very likely functions as an electro-receptor to help in the location of prey. Along the sides a pressure sensitive lateral line is well developed to sense the proximity of other fishes and surrounding structures- no doubt useful in the submarine caves where coelacanths pass their days. Two back, or dorsal, fins and one protruding beneath the nape of the tail are complimented by paired lobed pectoral and pelvic fins. These contain in their trunks bones mimicking those of Eusthenopteron which later developed into arms and legs. While coelacanths have not been observed to "walk" on the bottom, their pectoral and pelvic fins can be seen as "pre-adaptations" to land locomotion. Used under water their action maintains stability and balance. But in their cousin Eusthenopteron, the same action became four-legged land walking. Coelacanth scales are thick, and lined with serrated rows of hardened toothpick-pointed denticles. Perhaps most distinctive of all is the trilobated tail with its extra trunk and fin protruding from the middle. It was this feature that made fossil coelacanths so easily recognizable and helped clinch the case for the identification of the first living specimen.

Odd Behavior

When Hans Fricke and his submersible pilot first observed coelacanths at depth in 1987 they saw an odd bit of behavior. From time to time the fishes tilted forward, snouts down, and appeared to stand on their heads. Why? No explanation presented itself. Was this some ancient vestigial behavior? - or, as some speculate, a response to the submersible's electric field or searchlights? As of early 2000, the Fricke submersible visits offer the only direct observations of essentially unstressed coelacanth behavior, save for a brief view by divers off Sodwana, South Africa. Fin movements and swimming styles have been analyzed. Curiously, the coelacanth was never observed to use its paired pectoral and pelvic fins for bottom walking, a behavior that might have been expected of "Old Fourlegs." Coelacanths were found to congregate in submarine caves on the steep island drop off during the day, where they hovered without touching each other. Their white scale flecks, set against a cobalt blue body color offer excellent camouflage against the cave surfaces covered with white sponges and oyster shells. Fish which had been tagged with sonic devices were found to leave the caves at the same time late each afternoon to forage along the coastal incline during the night. The drift-feeding coelacanth is an opportunistic predator, scarfing up whatever it can with a suction action of the jaw and hinged cranium. Location of prey fish is possibly aided by a rostral organ (in the snout) which acts as an electric field receptor. The coelacanth's uncanny sense of timing and coastal navigation skills have yet to be explained. Another mystery is the whereabouts of the juvenile fish which are rarely seen in submersible dives and seldom caught by local fishermen.

Population / Location Debate

By doing a rough count of the number of possible coelacanth caves along the west coast of Grand Comoro island - and the number of fish per cave, plus the birth rate, Hans Fricke and associates came up with an estimate for the total coelacanth population in the low hundreds. However, there is some question if this estimate takes into account the known but unexplored coelacanth population at the nearby island of Anjouan, the unseen juvenile population, and the new number of potential embryos (26 as opposed to the previous 5) discovered in the 1991 Maputo, Mozambique trawled specimen. A total population count is also complicated by another until recently unresolved issue: Is the Comorian population the only one? Certainly the Comoro islands are the only place where regular annual catches of 6-8 coelacanths occur at Grand Comoro and 4-5 at Anjouan. But from time to time coelacanths turn up elsewhere: the one trawled off East London, in 1938; the one trawled off Maputo, Mozambique on August 11, 1991; the two netted off Madagascar in 1995/1997- along with other rumored Madagascar catches. Are these fish strays from the Comoros or are they representatives of satellite colonies? No one knows for sure. Fishing activities differ in the other locales and may not be such as to produce regular coelacanth catches. And finally, what about other islands in the Indian Ocean such as the Aldabras and Reunion - which have volcanic drop offs similar to the Comoros? Do they harbor as yet undiscovered coelacanth colonies? These speculations took a back seat to the 1998 confirmed identification by Dr. Mark Erdmann of at least two specimens from North Sulwesi, Indonesia at 10,000 kilometers from the Comoros with no apparent water current interactions, followed by submersible observation of two more in 1999, and the 2000 discovery of at least three coelacanths off Sodwana, South Africa. The Indonesian population appears to be distinct by DNA analysis, although the specimens at least superficially resemble the Comoran coelacanths. In any event, the coelacanth remains a very rare creature, probably deserving of its endangered Appendix I status in the C.I.T.E.S. listings.

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