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Since 1952, Comoran fishermen, fishing for oilfish, have caught approximately 200 coelacanths (from an estimated population of 500). Several coelacanths have been caught alive, but none have survived for long. Observations of the living fish (both from submarine and from the live fish that have been caught) as well as analyses of the tissue have taught us a great deal about these "living fossils." The fish are large—up to 2 meters and as much as 64 pounds—and usually blue with a white mottled pattern. They store low-density fats that help them maintain their buoyancy (and also render them inedible). They are not very active, and frequently "walk" on their fins from side-to-side. They eat other fish, as evidenced by their stomach contents. One female was caught alive, and she was carrying 26 near-term young. From her and other females coelacanth's reproductive habits are better understood. For about 13 months the female carries about 20 fertilized eggs the size of grapefruits (the largest eggs of any animal) (MacKenzie, 1995) (Milius, 1998). She then bears about 5 live young—the survivors who have eaten their siblings. Because the females bear live young and have such a long gestation period, the population is endangered if many pregnant females are caught and killed. Coelacanths are protected under an international treaty, but accidental catching and the demand in the black market likely results in the death of many. Many scientists were fearful of the extinction of the coelacanths—until July 30, 1998, when a live coelacanth was caught off a volcanic mountain of Indonesia 6,200 miles away from the Comoros Islands. The local fishermen are familiar with the fish, and even have a name for it—raja laut or "king of the sea" (Erdmann, et al., 1998). Erdmann and his wife had spotted a dead coelacanth in 1997 in an Indonesian market, but at the time they did not realize it was uncommon. The Indonesian coelacanth is apparently also Latimeria and was found in a habitat similar to the Comoran coelacanths. It is unlikely that the Indonesian coelacanth is a stray from the Comoran population because such a distance separates them and they have never been observed to migrate. Since coelacanths are well known to the local Indonesian fishermen this discovery is most likely not a stray, but a second population, independent of the Comoran population. Discovery of this second population is significant because it implies that coelacanth may be far more widespread than was thought. Erdmann, M.; Caldwell, R.L., and Moosa, M.K. 1998. "Indonesian 'King of the Sea' Discovered" Nature 395:335. Forey, P. 1998. Á Home from Home for Coelacanth" Nature 395:319-320. MacKenzie, D. 1995. "End of the Line for Living Fossil" New Scientist v.1978:14-15. Milius, S. 1998. "Second Group of Living Fossils Reported" Science News 154:196. Schliewen, U.; Fricke, H.; Schartl, M.; Epplen, J.T.; and Paabo, S. 1993. "Which Home for Coelacanth" Nature 363:405. Thomson, K.S. 1999. "The Coelacanth: Act Three" American Scientist 87:213-215. |
The term "Coelacanth" includes an infraorder of fish with unusual bony, fleshy fins. Coelacanths were first found in the fossil record in 1839, and, after Darwin's theory was introduced, they were thought to be the transitional forms between fish and amphibians. Fossils of the fish were found in rock strata that spanned from Upper Devonian to the Upper Cretaceous (supposed 360 m.y.a. to 80 m.y.a.). Since the fish had bony structures in their fins it was proposed that their fins were in the process of developing into feet so that they could walk on land. In the fossil record, there are approximately 70 species in 28 genera, almost all of which seem to have been deep-sea animals. Some of the fossils (six species—one from Permian and five from Triassic) were found in fresh water and four species may have been euryhalic (living in either) (Eldredge and Stanley, 1984). There was no indication that coelacanth existed after the Cretaceous "Age," and until 1938, evolutionists believed that they had died out as more highly evolved creatures replaced them. 
In 1938, however, a live coelacanth was discovered off the coast of South Africa. It was named Latimeria chalumnae. A second specimen was found by line fishermen off the Comoros Islands in 1952. The Comoros Islands are volcanic mountains that rise steeply from the ocean bottom. Since 1952 a population of Latimeria has been identified living in the volcanic caves below the Comoros Islands. Most of the fish which have been caught have been between a depth of 150 - 300 meters (with extremes of 70 - 600 meters). Before 1989, only three specimens had been found outside the Comoran population, and all three were down current of the islands. Observations of the fish's behavior and genetic studies indicate that all three seem to have been from the Comoran population and were carried away by the current (Schliewen, et al., 1993) (Thomson, 1999).