The Great Fossil Enigma Read Online Free PDF Page A

dollars was for fieldwork: two to three assistants for two months, one from Montana, one or two from Michigan; two rock saws; money for the “bulldozer” and “bulldozer” money for paying off the quarryman; truck rental; food and other necessities; and volunteers. Some money was also set aside for publication. The work would begin in June and run through July. Preparations now began, and Melton sent Scott photographs of the locality. When he saw them he was surprised and told Melton, “We may have to hire a man to use explosives.”

    In the spring of 1970, at the East Lansing meeting, Melton and Scott prepared to reveal all: “The sensational paper of the morning however was the one by W. Melton and Harold Scott on the progress they had made in studying the ‘conodont bearing animal’ found in the Early Pennsylvanian of central Montana. Harold Scott presented the paper, reconstructed the animal, named parts, and proposed physiological functions for the parts. He suggested the conodonts are ‘stomach teeth’ supporting a digestive organ. 3 specimens contain conodonts, but only one has the conodonts arranged like assemblages.” 17 By the repetition of structures, chemistry, knowledge of assemblages, and an awareness of “similar” creatures (like the famed near-vertebrate amphioxus), they had made sense of the flattened, seventy-millimeter-long, cigar-shaped animal. Their beast was “not comparable to…any living or fossil animal.” Its most standout feature was a distinctive black spot at its center. Above this was a triangular darkened patch within which the conodonts were found. This was the animal's gut, and in it the conodonts supported a filtering structure. From the animal's symmetry they imagined it “in almost perfect balance; very little energy would be required to move the animal in any given direction.” Melton and Scott supported their claims with a chart that gave percentage values to the accuracy of their interpretations. This revealed that they were certain of the orientation of the animal and that an organ holding the conodonts existed in the animal's gut. What they were uncertain about was the form of this structure. As they put it in the published account, “These facts, in addition to the generalized surviving shape of the animal, make it a distinct possibility that some ancestral conodont animal could have given rise to the vertebrates and possibly to the protochordates, though perhaps all protochordates had a common Cambrian ancestor.” The term protochordate was used to describe the non-vertebrate chordates such as amphioxus. In drawing these conclusions, Scott found British vertebrate paleontologist Bev Halstead's view that conodonts might belong to a filter-feeding, planktonic protovertebrate most useful. 18
    Some delegates expressed skepticism, believing this was an animal that ate the conodont animal. Others felt the fossils were inconclusive. One of the doubters, John Huddle, imagined Melton and Scott were disappointed by these interpretations, but the two men showed no sign of this after the event. Melton was thinking about the animal's biology on the flight back, clearly having enjoyed himself. He wrote to Scott to suggest that the tail of the animal must have contained stiffening rods to enable it to swim. Its midregion would flex a little perhaps and the head area not at all. Melton's arguments were precise and informed by what they could see in the specimens. Clearly the animal was still developing, and this required reasoned speculation. Having rented his house to the incoming departmental chairman, Melton now returned to the field with sufficient monies to continue the work.
    Scott could do little else but think about the meeting. Rhodes, who had written to him to congratulate him on his “excellent paper,” was now planning to produce a book to be published by the Geological Society of America and