Picks from the Past: May 1939

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If the ancient fossil coelacanth (Undina) could come to life, the living coelacanth might well swim toward it with all the signs of recognition it would exhibit for its own species. It cannot be said, of course, that the two could interbreed, but the living coelacanth possesses in its germ plasm, hereditary factors supposed have long since vanished from the earth, controlling among many other things the flipper-like lobed fin which was the predecessor of the mammalian hand and foot.

Until this discovery in South Africa upset all our man-made definitions, the span of the coelacanths on earth was thought to have ended with the Mesozoic Era, the time during which dinosaurs ruled the land. Yet even at that far distant period in earth history they were already the long-persistent survivors of much earlier ancestors, for their crossopterygian relatives lived far back in Devonian times, some 300 million years ago—long before the dinosaurs began, before there were any such things as land-living vertebrates. And it was these Devonian crossopterygians with their lobed fins, so prophetic of the limbs of later vertebrates, that were the direct ancestors not only of their little-changed descendants, the coelacanths, but also of the first amphibians, which were the first vertebrates to venture out of the water for a new life on the land. They in turn were the ancestors of the reptiles, birds and finally the mammals, including man. So it is that by looking at this living coelacanth we can see approximately what the ancient crossopterygians of 300 million years ago might have looked like, and we are thus enabled by the discovery of this living "flash-back" to get some idea as to how our own fish ancestors appeared in flesh and blood.

Until the living coelacanth was discovered, all the coelacanth fish and all the ancient crossopterygians (in which the coelacanth group is included) were known only from fossil forms; hence any restorations of these fishes as they might have appeared in life were based on remains of their bodies preserved in the rocks for 60 million years or more. Now that a "living fossil" has swum into our ken, so to speak, it is possible to see how nearly right were the scientific studies on the fossil specimens. Surprisingly enough, we see that the living fish is just what we thought it should be—in other words, the restorations based on fossils are now corroborated. Two of the reconstructed fossil coelacanths in particular, forms know as Macropoma and Undina, are closely approximated by the living fish. In the accompanying illustrations you can note the truly remarkable similarity between Macropoma as restored and the modern fish as it appears without benefit of human fallibilities and opinions. "Shall these bones speak?" Perhaps not, but the men who studied the bones spoke and drew pictures too, and now that the fossil has come to life it shows that the words and pictures were essentially correct.

To get back to the main story of the discovery of this fish—when Doctor Smith saw what a magnificent thing he had he promptly sent word to London, where, of course, there were not a few lifted eyebrows, for the dyed-in-the-wool scientist is sometimes a skeptical individual, especially when confronted with anything so astonishing as a resurrected crossopterygian fish. But Doctor Smith wrote a brief description wherein he gave a name to the new form, Latimeria chalumnae (in honor of Miss Latimer, who first recognized that this was an unusual specimen) and sent this to London with pictures of the fish. Then things began to happen.

There were not a few lifted eyebrows, for the dyed-in-the-wool scientist is sometimes a skeptical individual, especially when confronted with anything so astonishing as a resurrected crossopterygian fish.

There was a meeting of the Linnaean Society at Burlington House, at which some of the foremost experts on recent and fossil fishes were present. An examination of the pictures and of the description convinced these men—Sir Arthur Smith Woodward, formerly the head of the Department of Geology at the British Museum and one of the great authorities on fossil fishes, Professor D.M.S. Watson of University College, London, an outstanding worker on primitive land vertebrates and their immediate ancestors, Dr. E.I. White, in charge of fossil fishes at the British Museum, and Mr. J.R. Norman, in charge of recent fishes at the same institution. Their blessing was given to the discovery, the description was published, and soon it became a zoölogical sensation throughout the world, to be discussed and studied in classrooms and laboratories from New York to New Zealand.

Now there comes this question: Why wasn't Latimeria, the new coelacanth crossopterygian, discovered long before this? Several answers are possible. In the first place, it is quite possible that this fish has been caught before by fishing trawlers but was thrown back by incurious or indifferent men as "another catfish." That it may have come to the attention of men before is made probable by the statement of one resident of East London, who claims he saw one of these animals cast up on the beach some five years ago, but before he could get help to pull it in, it was washed away by the tide. Perhaps this is a deep-sea form that only on rare occasions wanders into shallow water where it will fall prey to the sweeping net of the trawler. Or what is more probable, it may be that Latimeria lives among the rocks and crannies of the ocean floor, so that even in shallow water it is ordinarily below the range of the net.

Whatever may be the explanation, it is a safe guess that there is going to be some intensive fishing and some excited fishermen off the South African coast during the next few years.