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COELACANTH - GREATEST ZOOLOGICAL SENSATION OR
GREATEST MISTAKE OF XX CENTURY SCIENCE? The greatest zoological record of XХ centiry was catching of Latimeria chalumnae - living coelacanth. It was made by Captain Hendrik Goosen. Identification was made by young scientist, miss Marjorie Latimer. Unindefinite fish was catched 22 December near beach of South Africa. Ms Latimer examined fish catching. She wrote “I noticed a blue fin sticking up from beneath the pile. I uncovered the specimen, and, behold, there appeared the most beautiful fish I had ever seen. It was pale, mauvy blue, with faint flecks of whitish spot. It had an iridescent solver-blue-green sheen all over. Just on 5 feet long. I gazed the fish. What could it be?” She invited professor J.Smith who identified the fishes as coelacanth - a living relict fossil. This was zoological sensation suggesting a new look on problem of evolutionary stability and changeability.
Wide spread opinion of paleothologists is that coelacanth was first vertebrate losted water and occupied earth, borning amphibia. They transformed into reptiles, which burned mammals and at last, man. Alive coelacanth shows that biological form may stay unchangeble during many hundred millions year. Coelacanth became a symbol of oldness, ancient and stable biological form. Nobody contested meaning of this find of 1938. No question about sence of this fish. Coelacanth exists and not like wildman is presented in many museums as dead and fixed. About 100 coelacanth were catched. The fish is studied seriously. 3 volumes encyclopedia on anatomy and physiology of coelacanth was published in France. There is no other fish which study was so complicated and hard. 50 anniversary of catching was celebrated by many scientific journals and institutions. 60 anniversary did not have such an effect. Sensation is over. Everybody having interest for the fish may vizit Berlin paleoyhological museun and to see body of the coelacanth.
But some questions exist till now. Is this find real? Is is mith?
After cathing in 1938, first coelacanth was got into museum of East-London, where worked miss Latimer. Professor Smith analized fixed body without internal organs. Professor suggested, that the fish is coelacanth from paleozoic age safing as specieas till modern time but increased in size. That was the begin of greatest zoological sensation of XX century. Coelacanth was considered by professor Smith as generum Latimeria (for memory of miss - conservator of museum). But professor Smith did not miss any doubt. He was unable to explane the following facts. Why coelacanth adopted for marsh lives at the deeps of ocean? The first coelacanth was catched at deep of 75 m where it was goted occasonally. The internal organisation was accorded to adaptation for deep water, high pressure and absence of light. But Smith missed all doubts. The coelacanth was only example during many years. Smith annonced prize, but no fishmen told on finds. New information was at september 1952 from Komor islands. Fishmen goted 3 000 km from East-London from big deeps second coelacanth. Is was at waters controled by France. Professor Smith having assistance by South Africa Army took coelacanth and transported it by military bomber to South Africa Union. There was possibility of attack Smith plane by french fighters and South Africa army was ready to little war “for fish”. The 2nd coelacanth was named by Smith as Melania. The majority of specialists are not agreeted with such identification and considell all coelacanth at single species Latimeria chalumnae. During 2nd half of 20 century about 100 coelacanths were found. 90% of them were males. According to population genetics data it means that population is under extinction.
What means modern coelacanth. According to modern systematics, all fishes are distributed into 3 taxon - Chondroichtes (Galeus, Raja), Osteichthyes, and lowest fishes - Dipnoi and Grossopterygii, including coelacanth. 300 - 350 thousand years ago this group was wide spread. Then coelacanth adopted to marshes deep 1 - 2 meter having lenght 15 - 30 cm were able to march from one bog to another. Their swiming bubble and scean were adoptyed to atmosphere air respiration. Their flippers close to legs were appropriate for transporting fron one marsh to another. Majoruty of scientists consider them as ancestors of amphibia. There is no real bones of prehistoric coelacanth. There are only replics on ancient silt. One is connected with marsh. There is no silt in ocean.
This ecological and paleoecological facts suggest any doubts on Smith identification. May be identification by Smits is mistake. He was not ichtyologicst but chemist. The modern latimeria has two differents from ancient one. The first is size. It is bogger than old many times. The evolution changing size must change relation of size. Moderd elephants have another proportions the ancient mammalia. Modern coelacanth is bogger than old one 3 - 6 times. Hence, its mass is bogger 27 - 200 times. Fish having such a mass was unable go at the earth by its flippers. The second difference is ecological one. Environment (umwelt) of modern coelacanth is other than ancient one. March and deep ocean are other environments. Does modern frog is able for adaptation for salt water and high pressure, out of light, safing proportion of body. Every zoologist will answer - no!
What is moder coelacanth-Latimeria? May be, professor Smith missed? There is such evolution apearence as convergence. C.Darwin knew abot one, but he considered it as exception. 1922 soviet scientists Lev Berg published evolution theory “nomogenesis” suggesting that convergency is general way of evolution. He considered many cases of common morphology of different taxons in different times. The brilliant example - the close shells of Molluscs and Foramenifera. According to Berg, the base of convergency is not environment, but the same low of form organisation. May be, Smith and other scientists were opherns by mistake based of unundertsaining of convergency and knowledge of russian researches? May be, Coelacanth-Latimeria is rare ancient specis, having morphological analogy to old coelacanth, but absolutely other species? May be, Smith like Columb found something great, but other, that he was looking for?
All this article is only hypothesis. The question on coelacanth is not resoulved. May be, it will not be resolved for everywhere?
Valentin Sapunov, professor of Biology
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