The Great Fossil Enigma Page 6

  Rohon confirmed the truth of their new worm four years later when searching through hundreds of conodont fossils collected from the same rocks in which Pander had found his specimens. Rohon was looking for evidence of fish teeth and found ten examples. These specimens were confusingly similar to conodont fossils but were nevertheless different. It made him even more certain that conodonts were worms, not fish. This discovery was picked up by Britain's leading geologist, Sir Archibald Geikie, who wrote in his popular textbook, “According to Dr. Rohon, however, all ‘Conodonts’ are not annelidian, but include undoubted teeth of fishes with recognizable dentine, enamel, and pulpcavity.”34 Something had been lost in translation, but fortunately for Rohon, no conodont worker ever noticed Geikie's interpretation.

  In truth, in the nineteenth century, few people looked at the conodont and puzzled over its meaning. The question that troubled science was whether the fossil signaled the early arrival of vertebrates into the history of life. Progress became a matter of assertion and counter-assertion based on evidence that was evocative yet ambiguous, contradictory, or simply misleading. Owen, the encyclopedist, felt he could delimit and weigh the possibilities using the concepts of “analogue” and “homologue.” In zoology, an analogue refers to a part of an animal that has the same function in different animals. The classic example is the dorsal fin of the shark, dolphin, and ichthyosaur – a broadly similar structure existing in unrelated fish, mammals, and reptiles. In contrast, a homologue is a structurally similar part that bears the same relations to other organs. The human forearm is homologous with the front leg of a cat by position, detailed structure, and embryological development. To our eyes there is an evolutionary relationship, but Owen was no overt evolutionist. Nevertheless, he understood that the detection of homologues was key to making sense of the animal world and the different categories of life that compose it. He knew that homologues provided reliable data about the zoological relationships between animals in a way that analogues did not.

  Owen's overview of the natural world permitted him to see both analogues and homologues, but it also convinced him that he understood the structure of the natural world well and thus, like Zittel, was predisposed to believe that such an early fish was unlikely. In contrast, specialist workers like Agassiz had a more focused outlook; they were more inclined to think within their own specialist boxes. Faced with an ambiguous fossil whose morphology said nothing particularly certain but spoke evocatively with its shape and color, these specialists were inclined to see the object as homologous with other objects in their understanding. They were more inclined to admit them into their territories because they did not fully comprehend the full range of possibilities. Specialization permitted the ambiguous to mislead; the analogue to be perceived as homologue.

  One other cornerstone of paleontology was illustration, and in Hinde's hands this was turned into a powerful pictorial argument. The technique was, however, turned against him by Zittel and Rohon. All these latter two men had to do was find the right image to convince the reader (and the non-German speaker). It was a more contrived argument than Hinde had produced, but readers are easily seduced by such things. Rarely do they consider the constructed and political nature of “logical” arguments.

  The resulting seesawing of opinion, some of it carefully judged but much of it ill founded, half-baked, or simply speculative, gave the object a growing mythology. Progress had been made, not least in Hinde's complex Polygnathus, and it seemed likely that it would continue into the next century. But the future was not so certain. American paleontology was about to undergo a revolution that would make it central to the nation's economic future. The conodont would be torn from this arcane debate over its biological affinity and made into something useful. The science of the animal was about to get a whole lot messier.

  In a few days the Eldorado Expedition went into the patient wilderness, that closed upon it as the sea closes over a diver…. I looked around, and I don't know why, but I assure you that never, never before, did this land, this river, this jungle, the very arch of this blazing sky, appear to me so hopeless and so dark, so impenetrable to human thought, so pitiless to human weakness.

  JOSEPH CONRAD,

  Heart of Darkness (1902)

  TWO

  A Beacon in the Blackness

  JUST THREE YEARS AFTER THE PUBLICATION OF PANDER'S BOOK on the conodont fishes, oil was discovered in the United States. A new black liquid flowed out of the ground and into American minds, altering them forever. (The conodont played no part in this discovery, but it too was altered). Notorious wastefulness followed. Successive wells ran dry. But calls for conservation fell on deaf ears, as America developed its obsession with the automobile. In 1921 there were 10.5 million motor vehicles on the road. By the end of the decade there were 26.5 million. Demand for oil grew exponentially, but without the predicted oil shortage as discovery continued to outpace demand. A plague of oil derricks advanced across the American landscape, from Pennsylvania, New York, West Virginia, Ohio and Indiana into California, the mid-continent (Kansas and Oklahoma), the Texas and Louisiana Gulf Coast, and Illinois.1 In the unregulated American economy, oil was soon in overproduction and prices plummeted, falling below that of water in some states during the drought years of the early 1930s. By then the once buoyant economy was in freefall and oil had played no small part in that collapse.

  As each state had located its own easy resources, so it profited from an oil boom, but as those wells ran dry, oil producers were forced to drill deeper and at greater expense. Ignorance of geology had led some wells to be drilled a thousand feet below the deepest productive horizon, while others had been abandoned before the oil-bearing strata had been reached. Such imprecision had accompanied attempts for coal in England more than a century before, but there a remedy had been found. The surveyor and engineer William Smith showed that rocks had a consistent order and that each contained its own peculiar fossils. This information was then used to correlate one stratum with another across country and to assign to each a relative age. This branch of geology – English geology,” Sedgwick called it – became better known as stratigraphy, and it dominated the science in the nineteenth century. It permitted ores, particularly coal, to be located intelligently and consistently rather than through luck and brawn. Oil is a rather different kind of mineral resource, but this same knowledge could help find it. There really was no excuse for committing these old errors in the New World, except, of course, for that same race for riches that had once fueled an English coal prospecting fever.2

  The science of geology eventually began to slowly enter the thinking of American oil companies around the turn of the century when it was understood that oil often accumulated under anticlines (rocks folded into arches). However useful such knowledge, it often proved insufficient. By 1913, for example, all the known anticlines in Illinois had been drilled. Oil production in that state fell and continued to do so until 1936. It only rose again when new technologies were introduced into oilfield exploration.

  Perhaps surprisingly, no one was consistently examining the cuttings brought to the surface in drilling operations. Ordinary fossils – the things Smith had used to order his rocks – were often destroyed by the drill. After World War I, however, attention turned to microscopic fossils, and particularly to those simple single-celled animals known as foraminifera. By 1925, the seven largest oil companies on the West Coast possessed laboratories that employed some twenty-three people in geological investigations. Soon nearly every wildcat was sampled and studied, and hundreds of geologists were engaged in this work. And as the paleontological community grew and diversified, so it professionalized itself. Fossil-focused organizations burgeoned. The Paleontological Society was established in Baltimore, Maryland, in 1908, when “the immensely rich oil fields of the Mid-Continent were being discovered.” The American Association of Petroleum Geologists (AAPG) was founded in Tulsa in 1917. Its Bulletin grew from 159 to 1,319 pages per annum in just eight years. By
then it was issued monthly and was under the control of editor extraordinaire Raymond Moore of the University of Kansas. Its physical weight spoke of how geology in America had changed: The science was now dominated by a deeply utilitarian outlook that sought only to serve the needs of business. The Society of Economic Paleontologists and Mineralogists (SEPM) was established about a decade later, at a meeting of the AAPG, again in Tulsa. SEPM’s focus was to be devoted almost entirely to the utilitarian science of microscopic fossils, or microfossils. Its Journal of Paleontology first appeared in July 1927.3

  With this changing professional demographic, paleontology more generally underwent a shift of emphasis: Universities began to introduce courses in “micropaleontology.” At the University of Chicago, Carey Croneis set up a masters program in the subject, converting the top floor of the Walker Museum into a laboratory. Paleontological doctorates and masters dissertations were soon dominated by this new specialism. Increasingly, paleontology took on a business aspect and began sweeping up every possible tiny fossil, turning fossil curiosities into objects of great utilitarian potential. Laurence Sloss, a student at Chicago in the 1930s, later recalled how the Chicago department's “graduate body of mature men and women” swelled at this time “because their jobs in oil and mining had evaporated with the Depression.”4 University departments were reinvigorated by this influx and there was an explosion of interest in these newly fashionable microfossils.

  It was one thing to know that microscopic fossils might be useful, but in the 1920s it was difficult to know which ones. Many early studies considered them all. U.S. Geological Survey (USGS) worker Paul Roundy, a recent convert to this microscopic world, now understood that some foraminifera were useful but that many were not. Sponge spicules and tiny snails were sometimes numerous but hardly studied. Worm jaws were too rare. Ostracodes, or “seed shrimps,” on the other hand, were abundant and most important. Plant seeds and spore cases held potential but again had attracted little attention. On the conodonts, however, Roundy was emphatic: “These I believe will prove to be of considerable importance in stratigraphic work when they have been more fully studied.”5

  Roundy was at the time investigating Mississippian (Lower Carboniferous) rocks in Texas. Rocks of this age and type had, since 1912, fueled a feud between government geologists. They were part of a sequence of black shales that occur throughout much of the interior of the United States and part of Canada and range “from a featheredge to several thousand feet in thickness.”6 At some point in this shale sequence the Devonian passes up into the Mississippian, but geologists could not agree precisely where. Knowing the position of this boundary was critically important and not something that could be ignored or worked around. But the fossil evidence, which in other parts of the world had decided the matter, remained elusive or contested in North America. The problem proved persistent and threatened to make a nonsense of the burgeoning science. Even in 1931, it was still possible to claim that rocks of this age “have almost as many names as there have been sections studied”: Chattanooga, Hardin, Berea, Bedford, Sunbury, Saverton, Grassy Creek, New Albany, Sweetland Creek, Arkansas, Woodford, Cleveland, and Ohio.7 Different names for essentially the same thing, and the same name for different things. What had started as the “Ohio Shale problem” soon became a more pervasive “black shale problem.”

  At the heart of this controversy was E. O. Ulrich, who by the beginning of the twentieth century had risen to become a USGS geologist of some distinction. Known for his outspoken views, one friend half-jokingly remarked, “The trouble with you, Ulrich, is that you think you are God.” Ulrich had been at his most godlike in 1911, when he published a huge and radical revision of the older fossiliferous rocks (the Paleozoic). Shaped by his own peculiar outlook and his dislike of the “paleontological autocrat” who privileged fossil evidence above all else, he refashioned the geology of America. So all-encompassing was the resulting publication that all who now studied these older rocks had to pay attention to his opinions, and this was particularly true of those wishing to resolve the problem of the black shales. For here, Ulrich had been at his most contentious. With a few taps of his typewriter keys, he had moved great swathes of black shale into the Mississippian. Providing little evidence to support his geological choreography, opinions became inflamed. His only follower was his protégé, Ray Bassler, who published a supportive paper the same year. A fellow Cincinnati geologist, Bassler as a boy had adopted Ulrich as “Uncle Happy” and followed him to Washington, where he would establish a career for himself as a paleontologist at Columbian University (now George Washington University) and the U.S. National Museum (the Smithsonian).8

  In February 1912, Ulrich's colleague at the Survey, Edward Kindle, pressed Ulrich to publish his data. Kindle did so in print, demonstrating his superior knowledge of the black shale problem and implicitly suggesting that Ulrich and Bassler lived in a hypothetical world far removed from reality: “This opinion concerning the age of the Chattanooga shale is comparable to some which have followed it in the poverty of evidence on which it rests and the positive phrasing which might mislead one unfamiliar with the subject to suppose that it represents an established fact.” It was now that the conodont was introduced for the first time as a key actor in the debate. Kindle continued, “Although generally considered to be nearly barren of organic remains, the writer has found the carbonaceous beds of the Chattanooga shale to carry a conodont fauna which is quite as abundant in the lower or Huron shale of Ohio and Kentucky as it is in the upper or Cleveland shale. These minute but beautifully preserved fossils may be obtained at any locality and at any horizon in the black shales from Lake Erie to Alabama. These fossils have long been known in the Ohio Shale, but with the exception of a very few species have remained undetermined and undescribed. When they have been described and the species which are confined to the upper and lower horizons of the shale distinguished, they will prove to be an invaluable aid in correlating the different parts of the Ohio Shale with their equivalents in the Chattanooga Shale in Kentucky and further south. Until this has been done, however, any attempt to make use of these fossils in correlating subdivisions of the Ohio and Chattanooga shale must be considered premature and futile.” Bassler had also observed these fossils in the shales but had seen no particular use for them. Now, with Kindle's words, the conodont was thrust into the limelight.9

  Kindle believed the black shales were mainly Devonian. Indeed, this was the orthodox view until overturned by Ulrich. Kindle knew Roundy already agreed with him and he wrote to other authorities to get their opinion on the matter. Among these was E. B. or “Ted” Branson, a fossil fish specialist who had collected from the black shales. Branson, who was soon to switch his focus to conodonts, was only too happy to agree with Kindle. The Survey's specialist in Carboniferous fossils, George Girty, on seeing Kindle take his stand against Ulrich, asked him for his opinion on the Bedford Shale. Girty admitted that for years he had been “playing the pendulum” on the subject, repeatedly changing his mind. He now supplied Kindle with evidence to convince him of its Devonian age, telling him that on this matter they should stand together. Kindle was delighted to have such an experienced authority on his side. Now the USGS was split into opposing factions, and Ulrich led the minority.

  Ulrich acted quickly to rebuff Kindle's attack, publishing his data in the August issue of the American Journal of Science. Probably as a result of the editor's sleight of hand, Kindle's counterview appeared in that same issue, just a few pages later. The detail of their arguments need not concern us: Ulrich and Kindle were now head to head, the tenor of their papers scarcely concealing their personal animosity. Ulrich's arrogant and lofty pugnacity was met with Kindle's blows below belt. To the falsetto-voiced Kindle, Ulrich was a descendant of the German geological pioneer Abraham Werner, a man long stereotyped as the overly theoretical Antichrist of modern geology. Behind the scenes, Survey geologists discussed the assault on Ulrich's position as many of his key strata began to fall to t
he other side.10 And when the appointment of a new Devonian specialist came under discussion, there was a campaign for it not to be an Ulrichian.

  Matters came to a head when a paper that had been submitted for publication was rejected by a referee. Neither Kindle nor Ulrich had written the paper, but Kindle had supplied the fossil identifications and Ulrich had been the referee. Kindle became enraged when he heard the news and wrote to the USGS’s chief geologist, David White, telling him, “You will find it increasingly difficult to get any self-respecting palaeontologist to take a place in your organization, in which a man with Ulrich's peculiar views is invited to dominate everything relative to Paleozoic palaeontology…. You know as well as I do that Ulrich delights in scrapping on any pretext whatsoever.”11 He sent the letter to Girty, who checked into the matter. He found that Kindle was inventing demons. Ulrich had behaved impeccably. But by then Kindle had had enough and he left to join the Canadian Survey, there to rise to an elevated position (not least metaphorically so, for Mount Kindle was named in his honor).

  The excess heat in the black shales dispute dissipated with Kindle's departure. In what was still a tiny geological community, where everyone knew everyone else, individuals were inclined to takes sides, and the science and its personalities became inextricably entangled. All, however, agreed on one thing: The conodonts might provide a solution to the black shales problem. By 1914, Ulrich believed he possessed distinctive conodont faunas that supported his views.12 The fossil as a result moved closer to becoming a utilitarian object, valued only for what it could tell the field geologist. “The study of fossils apart from their stratigraphic relations is pure biology,” Ulrich wrote.13 And those who thought otherwise, in oil-obsessed America, were increasingly finding themselves in the minority.