A Fish Caught in Time: The Search for the Coelacanth

  • Samantha Weinberg
Fourth Estate: 1999. 239 pp. £13.99
Resting in peace: Smith's hand lies on the head of the second coelacanth found off the Comoro Islands.

In December 1938, the first living coelacanth (Latimeria chalumnae) to become known to science was accidentally caught near East London in South Africa. Coelacanths were thought to have been extinct for 70 million years — since the late Cretaceous — hence the sensational impact of this discovery of a ‘living fossil‘. But, in addition to this astonishing survival, the coelacanth revealed the anatomy of the soft tissues of ‘crossopterygian’ fishes, thought to have been forerunners of the four-legged vertebrates, or tetrapods. Therefore, it raised considerable interest among evolutionary biologists and palaeontologists. Samantha Weinberg's book describes the history of the discovery of the living coelacanth, and the lives of the women and men involved in it.

Several books have been published previously on the story of the Comoran coelacanth, including Old Fourlegs by J. L. B. Smith (Longmans, 1956), who first described the fish and named it after its discoverer, Marjorie Courtenay-Latimer. But Weinberg's book also includes the account of the recent discovery of the Indonesian coelacanth. In her book, both discoveries sound like detective stories, with obscure political and ethical intrigues, often involving French scientists.

The first coelacanth was mounted in such a way that little of its anatomy was available to Smith, who was eagerly waiting for a second specimen. Thanks to Eric Hunt, the second coelacanth turned up in 1952, but in the Comoros. The way it was taken from the Comoros, then a French colony, by Smith himself, on board a plane chartered by South Africa's prime minister, Daniel Malan, raised frustration among French scientists and led the French government to ban foreign coelacanth investigators. Subsequently, most coelacanths caught in the Comoros were sent to Paris and then either used for anatomical study or donated to major scientific institutions, with the stipulation that they would not be dissected.

Smith accused the French of hindering the scientific study of this extraordinary fish, and appealed, in vain, to an international research programme. Weinberg clearly sympathizes with Smith on this matter. Alas, generosity is rare when a country possesses an invaluable research subject. In 1952, French science was recovering from the war and the sudden discovery of the coelacanth in French waters could not possibly be ignored. Whatever judgement one may pass on the appropriation of the coelacanth by the French, or, conversely, on the cavalier expedition of Hunt and Smith, the resulting monographs on the anatomy of Latimeria, by J. Millot and J. Anthony (and D. Robineau for the last volume), remain a masterpiece. Nevertheless, many French zoologists felt that Smith should have been closely involved in the anatomical study of the fish. After all, neither Millot nor Anthony were initially ichthyologists, whereas Smith was in 1952, at any rate.

The discoverer of the Indonesian coelacanth, Mark Erdmann, had a radically different attitude from Smith's, as he immediately donated the first specimens to an Indonesian institution and established an agreement for a US–Indonesian joint study of the specimen, in particular a molecular sequence study to check whether it is the same species as the Comoran coelacanth. All went smoothly, and the discovery of the Indonesian coelacanth appeared in Nature (395, 335; 1998) in September 1998. Mark and Arnaz Erdmann were heroes, as Courtenay-Latimer and Smith had been in 1939, but with, in addition, a fairy-tale atmosphere because this latest discovery was made during the young couple's honeymoon.

Then, in April 1999, came the shock: the French, “inevitably” (in Weinberg's words), published a paper aimed at giving a scientific name to the Indonesian coelacanth (L. menadoensis, after Menadotua Island, where it was caught) on the basis of a quick morphological and molecular sequence analysis that suggested some difference from L. chalumnae. In fact, the authors of this note are both French and Indonesian, with Laurent Pouyaud (not Pouyard) as the first and only French author. Apparently, the Indonesian authorities gave them free access to samples from the specimen donated by the Erdmanns. To play devil's advocate, one may say that the Indonesians did exactly what Smith wanted the French to do. Unfortunately, this new page of the eventful history of the coelacanth came too late to be dealt with in detail by Weinberg, and is only accounted for in a justifiably angry footnote.

The naming of the Indonesian coelacanth is at odds with the ethics of systematics: no reference to the discoverer of the specimen (notoriously studying it), no designation of the holotype (admittedly, a single specimen to date), no museum number and, above all, a wide spreading of the new name in the press before the scientific publication appeared. Immediately, heated debates occurred among systematicians as to whether the name was acceptable, or should have the authorship of the first journalist who published it in a daily newspaper, instead of that of Pouyaud and his co-authors. But, according to the requirements of the current edition of the International Code of Zoological Nomenclature, there seems to be no reason to reject it and its authorship, whatever its ethically questionable background. Further studies, however, may prove L. menadoensis to be a mere synonym of L. chalumnae. The close collaboration between the German Hans Fricke and the French Raphael Plante in the first successful observations of the Comoran coelacanth alive and well in its natural environment contrasts greatly with the history of the naming of the Indonesian one.

Weinberg explains why the coelacanth is interesting and at the same time disappointing, in the context of the question of the origin of tetrapods. She also gives an account of the discovery of the lungfishes, in the nineteenth century, which raised the same excitement as that of Latimeria. However, this section and the section about fossils contain a few minor mistakes (for example, the spiral valve is not in the stomach, but in the intestine). The coelacanth is currently classified among the sarcopterygians (vertebrates in which the paired fin/limbs skeleton articulates to the girdles by means of a single bone, the humerus and the femur in tetrapods). Along with lungfishes, the tetrapods and several fossil-fish groups, it shares very few advanced characters with the tetrapods, and this puts it somewhere near the base of the sarcopterygian tree. In a sense, the coelacanth tells us more about the primitive condition of all bony fishes than about the origin of tetrapods.

As a whole, the book reads well, like an adventure story, with amusing and charming anecdotes about the lives of the protagonists. To a scientist, it may be frustrating not to read more about how palaeontologists reacted to the discovery of Latimeria and how it could test their previous reconstructions. Although, admittedly, most palaeontologists who dealt with coelacanths and other fossil sarcopterygians before 1938 and experienced the pre- and post-Latimeria times are now dead, very few have written about this.

The conclusion of the book somewhat tails off. It mentions the possibility of finding more coelacanths elsewhere in the world, which is plausible, and the need to protect and “leave the coelacanth in peace”, which is wise. Nevertheless, the author should perhaps have questioned scientists about what more they expect from this fish. Its behaviour is barely known and, above all, its embryonic development is totally unknown. Knowing how the strangely articulated braincase or the fins of the coelacanth develop would be just as important as what we already know of its anatomy, in particular for understanding the early evolution of bony fishes and sarcopterygians. This is perhaps the next challenge for the forthcoming century.

Lay readers will certainly enjoy A Fish Caught in Time, but it can also be recommended to students and zoologists who are too young to have experienced this extraordinary zoological adventure.