The Dragon Seekers

by McGowan, Christopher

• ISBN13: 9780738202822
• ISBN10: 0738202827
• Format: Hardcover
• Copyright: 2001-04-01
• Publisher: Perseus Books Group

Summary

The dramatic story of how a group of nineteenth-century fossilists forever changed our view of history--and laid the groundwork for the Darwinian revolution

Author Biography

Christopher McGowan is a full professor in the Department of Zoology at the University of Toronto and Senior Curator of Paleobiology at the Royal Ontario Museum.

Table of Contents

Preface	p. ix
Acknowledgments	p. xiii
In the Beginning	p. 1
Dragons by the Sea	p. 11
The Scriptures and the Rocks	p. 29
Chalk Pits and Leeches	p. 41
The World of Darkness	p. 51
Revelation	p. 65
The Tooth of the Iguana	p. 81
Just Causes	p. 93
More Giants	p. 105
Improving on Nature	p. 117
Mr. Konig Regrets	p. 133
The Professor and the Naturalist	p. 149
Landslides, Glaciers, and Riots	p. 165
Of Dinosaurs and Species	p. 175
Decline and Fall	p. 193
Beside the Sea	p. 203
Notes	p. 219
Further Reading	p. 235
Sources of Illustrations and Credtis	p. 239
Index	p. 241
Table of Contents provided by Syndetics. All Rights Reserved.

Excerpts

Chapter One

In the Beginning

It is a remarkable fact that the human mind, which has had a presence on Earth for over 2 million years, only began rational thought on how species came into existence during the last three centuries. Prior to this age of enlightenment people were content with mythological explanations. These were later supplanted by formal religious beliefs, as in the Genesis account of the Creation.

    Fossils, which are central to the issue of origins, have been known since the classical time of the Greeks. But it was not until the second half of the eighteenth century that the stony objects, dug from the ground, were correctly interpreted as the remains of former inhabitants of the Earth. Even then, the intellectuals who studied fossils were often unable to identify them correctly, far less to place them in their proper context. For example, the bilobed bony fossil that Robert Plot of Oxford ascribed to a giant human in 1676, and which R. Brooks labeled as Scrotum humanum in 1763, was actually the lower end of the femur of a dinosaur. Dinosaurs, and their reptilian kin, therefore passed unrealized, if not unnoticed, until the early part of the nineteenth century.

    Why did it take so long for paleontology--and even longer for evolutionary studies--to come of age in this age of discovery? This question is made all the more perplexing when account is taken of the progress that had been made in many other branches of science by the nineteenth century. John Dalton (1766-1844), for example, derived his atomic theory of matter in 1803, Isaac Newton's (1642-1727) laws of motion were formulated over a century before, in 1687, and Edward Jenner (1749-1823) introduced immunization against smallpox in 1798. The reason for the differential development of the various branches of science probably has much to do with the graded response of the established church, specifically the Anglican Church in England. English theologians and clerics had no argument with those who tinkered with chemistry or physics, but intellectuals who questioned the biblical account of the Creation could expect the full and considerable weight of the church to bear down upon them.

    The church's role in slowing intellectual progress in unraveling the remote past was much greater in Britain than in France. The French Revolution of 1789 broke the powerful grip the Roman Catholic Church had on the state, creating an intellectual milieu unfettered by religious dogma. It was in this secular environment that some of the most radical ideas of the age were spawned, such as Jean-Baptiste Lamarck's (1744-1829) ideas on the transmutation of species. But in Britain the Anglican Church was still an integral part of the establishment. Intellectuals in pre-Darwinian Britain therefore lacked the freedom of expression of ideas that ran contrary to the Bible--in the same way that today's science teachers are constrained in North American school districts where fundamentalists hold political power. The Genesis account of the Creation therefore remained the predominant view in Britain for most of the nineteenth century.

    It is difficult for us in our modern world to appreciate the powerful influence the church had over philosophical and scientific issues during Darwin's (1809-1882) time. Except to many present-day Christian fundamentalists, the Book of Genesis has no relevance to the way we interpret the natural world and its long geological history. But it was not so when early fossilists attempted to interpret the remarkable creatures they discovered. Back then, the biblical account of how living things came into being was the accepted and seldom questioned truth. Charles Darwin himself records how orthodox he was in his religious beliefs when he was cruising aboard the Beagle (1831-1836), at least on moral issues, and there is no reason to suppose this did not extend to the Genesis account of creation too:

... I remember being heartily laughed at by several officers (though themselves orthodox) for quoting the Bible as an unanswerable authority on some point of morality.

    The early fossilists, like most other intellectuals of their time, recognized that the fossilized creatures they studied were no longer in existence. But others denied the concept of extinction on religious grounds. The idea that any of God's creatures had failed to survive cast aspersions on his wisdom and was thereby untenable. They argued, instead, that the supposedly extinct creatures simply lived on, undiscovered, in unexplored parts of the world. This may have been a plausible argument for small organisms, like ammonites (shelled marine animals), which could conceivably have survived in unexplored ocean depths, but, as the French anatomist Georges Cuvier (1769-1832) pointed out, this was highly unlikely for large land animals. Cuvier made a compelling case for extinction through his work on the large fossil mammals excavated near his Paris home.

    Georges Cuvier was probably the greatest intellect of his age. Men like William Buckland (1784-1856), the first professor of geology at Oxford University, avidly read his published works, deferentially referring to his views on fossils, anatomy, and geology as the final authority on the subject. Cuvier's opinions were widely sought, often by sending problematic fossils to him at the Muséum National d'Histoire Naturelle in Paris, or by visiting him in person.

    Cuvier pioneered the use of comparative anatomy to distinguish between species. For example, by making detailed comparisons of their skeletons, he demonstrated that the two living species of elephant (Asian and African) were separate species. Among their many distinguishing features, the Asian elephant ( Elephas indicus ) has a domed skull, compared with the African elephant's ( Loxodonta africana ) lower-crowned cranium; its tusks are more slender; it has twenty pairs of ribs instead of nineteen, and consequently twenty thoracic vertebrae (those between the neck and the pelvis to which the ribs attach) rather than nineteen; and their spines decrease in height gently toward the pelvis, rather than abruptly. These skeletal differences give the two living elephants markedly different profiles. The Asian elephant seems to have a prominent bump on its head, and its back is gently arched between shoulders and hips. The African elephant, in contrast, has a much flatter head, and the mid-back region is dished. Both species have flattened grinding teeth, and these are transversely ridged with raised enamel plates, like a coarse file. However, as Cuvier noted, there are relatively more ridges in the Asian elephant, and their edges lie parallel to one another, whereas in the African species the edges follow a zigzag pattern.

    Using the same comparative methodology, Cuvier showed that the mammoths, and their relatives the mastodons, which do not have ridged teeth, were separate species from the living elephant species. Having established that mastodons and mammoths were distinct species, he argued how unlikely it was that such colossal animals could remain undetected in the world. This was especially so given that other large beasts, such as the elephant, giraffe, rhinoceros, and hippopotamus, had been known since the time of the ancients. His forceful arguments for the disappearance of mammoths, mastodons, and several other large terrestrial mammals convinced most people of the reality of extinction.

    Cuvier's fellow countryman Lamarck, however, disagreed. He considered that all species found in the fossil record had become transmutated into modern forms, making extinction an impossibility. According to Lamarck's transmutational theory, species were continually changing into other species. The species was therefore an artificial concept, not a natural entity. Lamarck thought the transformation came about by the acquisition of acquired characteristics from previous generations. In the often-cited example of the mechanism, the giraffe had acquired its long neck over countless generations of stretching up into trees to reach higher branches. The slight increase in neck length of each generation was passed on to the next one, thereby transforming the short-necked ancestor into its long-necked descendent. Lamarck's conjecture was the first serious attempt at a theory of evolution, though it was referred to as "transmutation" rather than "evolution"--the latter term did not come into common usage until well after the publication of Darwin's Origin of Species .

    Cuvier, like most other intellectuals of the time, rejected Lamarck's supposition, considering that species were both real and unchanging. His opposition to Lamarckism was primarily an opposition to the idea of the transmutation of species, which denied the reality of extinction. Cuvier had little interest in the question of species transformation per se--as far as he was concerned geology had no evidence to offer on how species may have come into existence, so there was no justification in speculating on the matter.

    An opportunity for the two Frenchmen to test their conflicting views on the permanency of species arose when large numbers of mummified animals were collected from some ancient tombs during Napoleon's expedition to Egypt. The age of the animals--cats, dogs, ibises, raptors, monkeys, and crocodiles--was admittedly only a few thousand years, but, during Cuvier's time, this was thought a sufficiently long period to show some indications of change. Careful comparisons showed no differences between the ancient animals and their modern counterparts, vindicating Cuvier's conviction of the permanence of species. Permanence to Cuvier, of course, meant that species did not change (evolve) through time, not that they were immune from extinction.

    Cuvier also used comparative anatomy to elucidate an animal's lifestyle from its skeleton. Thus the lion's trenchant teeth, precision jaw joint, and piercing claws--the hallmarks of its carnivorous diet--could be used to identify the same traits in fossil skeletons.

    But a larger intellectual challenge than interpreting lifestyles of fossil species was accounting for their present-day distribution. Fossils of marine animals were commonly found on land, sometimes at great heights above sea level, showing that considerable upheavals must have occurred during the long history of the Earth. Cuvier noted that whole groups of organisms were replaced by others during these recurring catastrophes. His studies of the sequences of fossils in the sedimentary strata had shown him, for example, that the first reptiles preceded the first mammals, and that the fossil mammals he unearthed from strata in the vicinity of Paris were different from modern ones. He also found that the proportion of modern animals increased as the rocks became progressively younger. He referred to the recurring catastrophes as revolutions .

    Although far-reaching in their effects, he thought the revolutions were rare events, of relatively short duration, punctuating long periods of stability. These long episodes of tranquillity were evidenced by extensive formations of evenly deposited strata, such as the Chalk, a Cretaceous formation that in southern England reaches thicknesses of several hundred feet. The last of these revolutions saw the demise of mastodons, mammoths, cave bears, woolly rhinoceroses, and many other large mammals from North America and northern Europe. This last catastrophe bore all the signs of the inundation of land by water, incorporating heaps of debris and rounded pebbles into the strata. For Cuvier this revolution was no different from all the others that had wreaked havoc on the world. But for others, like Buckland, it was geological proof of the Noachian flood.

    Cuvier did not think the revolutions could be accounted for by processes still operating in the modern world. He avoided speculating on what these other causes might have been, but there is no reason to think he suspected the hand of God: Cuvier, unlike Buckland, kept science separate from religion. Cuvier presented his ideas in a four-volume work entitled Recherches sur les ossemens fossiles , first published in 1799. This influential work, which Cuvier revised many times, was translated into several languages and was widely read. Although his radical ideas of revolutions, or catastrophes, were rejected by some intellectuals, many others, like Buckland, readily accepted them, adding his own theological spin. Catastrophism enjoyed widespread popularity for many years, but was eventually replaced by a more gradualistic view of earth history, as championed by Charles Lyell (1797-1875). Lyell sought explanations for past geological changes in terms of processes occurring in the modern world. This mechanistic explanation of past geological events is often referred to as uniformitarianism .

    Buckland, like most other rational thinkers of his time, believed that God had directly created the world, and every living creature and plant individually. He also believed, like most, that Homo sapiens , made in God's own image, was the last and most special of all His acts of creation. Man occupied a special and favored place. He had dominion over the entire globe and all its inhabitants. These other creatures were placed on Earth specifically for his use and subjugation, as told in the Book of Genesis. Buckland also believed in a universal flood that had inundated the world, destroying everybody and everything that had lived on the land, save those taken aboard Noah's ark.

    Although the biblical account of the Creation was broadly accepted, there was some latitude in the interpretation of the precise wording of the Scriptures. Some Christians accepted the Genesis account verbatim (as some do today), believing, for example, that God literally created the entire world in six days. But others, including Buckland, chose to take the six days as an allegory for a much longer time period. As geological knowledge progressed, greater latitudes were needed to accommodate science within the Scriptures, and a belief in the literal truth of Genesis became untenable for many. For example, it was once accepted that sedimentary (layered) rocks were formed over a period of months, as the sediments settled after the Noachian flood. However, when it was recognized that sedimentary rocks had a total thickness of many thousands of feet, such a short time frame became unacceptable. For Cuvier, Buckland, and many other thinkers, the Earth was obviously at least tens or hundreds of thousands of years old.

    Buckland began his career as an ordained minister, and spent much of his academic career at Oxford documenting the geological evidence for the Noachian flood. But as new discoveries were made, even this most hallowed of biblical truths could no longer be supported by the geological record. Buckland eventually abandoned flood geology in favor of glaciation, which attributed such phenomena as the carving of valleys to the action of glaciers moving over the land. But his belief in the biblical flood was unshaken; only his interpretation of the geological evidence for the event had changed.

    Buckland died in 1856, three years before publication of the Origin of Species . Had he lived long enough to read Darwin's account of how species had become transformed--transmutated--over long periods of geological time, he might just have been convinced. Darwin's arguments had, after all, persuaded many others to abandon the almost universal conviction of the permanence of species. But these minds may not have been changed if Origin of Species had been published many years earlier. Writing in 1876, seventeen years after its publication, Darwin recorded that "I gained much by my delay in publishing from about 1839, when the theory was clearly conceived, to 1859...." He noted that the advantage of the delay had sometimes been attributed to peoples' minds becoming more receptive to the idea that species were not permanent. He himself acknowledged, in the third edition of the Origin (1861), the important role of earlier work in "removing prejudice" and "preparing the ground" for reception of his ideas on the transmutation of species. But he did not think this was the primary benefit. Rather, he thought the delay gave time for the accumulation of "innumerable well-observed facts ... in the minds of naturalists, ready to take their proper places as soon as any theory which would receive them was sufficiently explained."

    Much of the change in the intellectual climate in Britain is attributable to the work of early-nineteenth-century fossilists. This is not because they actively prosecuted the change--most of them, on the contrary, were firmly committed to the biblical account of the Creation and to the permanence of species. But their discoveries, by giving exciting new glimpses into the incredible world of the past, raised new and challenging questions. Consider, for example, the ichthyosaurs ("fish lizards"), a group of fishlike reptiles that were contemporaneous with dinosaurs. Their discovery raised the possibility of a link between fishes and crocodiles. Similar questions of linkage were raised with the discovery of another kind of marine reptile, the plesiosaurs. The Reverend William Conybeare (1787-1837), who coined the name "plesiosaur," thought they formed a link between modern reptiles and the more highly specialized ichthyosaurs. However, he vehemently denied this was evidence for a Lamarckian transformation of species. Instead, he considered that the linkages among different kinds of animals bore further testimony of the richness of God's creative design. Although Conybeare rejected transmutation himself, the fact that the issue was being aired publicly contributed to the change in intellectual climate. So too did the fossilists' discussions of more mundane issues, like the Noachian flood. The final defeat of flood geology, after years of public debate, ensured that this particular issue would not have to be revisited. But perhaps the greatest significance of its rejection was that it signaled the loosening of religion's grip on science.

    Aside from their helping to pave the way for Darwin--even if unwittingly--the most exciting accomplishment of the early fossilists was the revelation that the Earth was once inhabited by incredible, often gigantic, reptiles. Even in our modern world of wonders, we still marvel at the latest dinosaur discoveries, so imagine what it must have been like back in Buckland's time. Those were the days when menageries stunned visitors with their first glimpses of elephants, giraffes, and other exotic creatures. When people learned that monstrous reptiles, many times larger than elephants, once roamed the land, they must have been overawed.

    The early fossilists, our dragon seekers, had a rich pageant to unfold. The players were almost exclusively men, which is not surprising in those disenfranchised times. There are three principal characters besides Buckland in our narrative: Mantell, Owen, and Hawkins. Gideon Mantell (1790-1852) was a country physician who discovered some of the world's first dinosaurs. He also did much to popularize the new sciences of geology and paleontology, through his books and popular public lectures, delivered before capacity audiences. Richard Owen (1804-1892) also began his career as a physician, but left medicine to become one of the greatest anatomists and paleontologists of all time. His many achievements include the coining of the name dinosaur . The eccentric Thomas Hawkins (1810-1889), a man of independent but probably limited means, amassed a spectacular collection of ichthyosaurs and plesiosaurs, which he eventually sold to the British Museum. After the completion of the sale it was discovered that his specimens were not all they had appeared to be. The ensuing scandal reverberated all the way to the British House of Commons.

    Besides Darwin and Cuvier, minor roles were played by Conybeare, Lyell, and Agassiz. Conybeare, close friend and confidant of Buckland, was one of the brightest and most competent geologists of his time. He was the leading authority on ichthyosaurs and plesiosaurs, and could have had a distinguished academic career. Instead, he chose to devote his life to the church. Charles Lyell, a lawyer and former student of Buckland, revolutionized the young science of geology with his Principles of Geology , in which he advocated uniformitarianism. Darwin took Lyell's first volume of Principles on the voyage of the Beagle , and was much influenced by what he read. In later years he would use the principle of uniformitarianism to investigate the origin of new species by seeing how selective breeding had produced such change in domestic species. Louis Agassiz (1807-1873), a Swiss naturalist and specialist of fossil fishes, is best remembered for his recognition of the Ice Age (Pleistocene), and his advocacy of the role of glaciers in bringing about physical changes in the Earth's crust that had formerly been attributed to the Noachian flood.

    Among these eminent gentlemen was one leading lady: Mary Anning (1799-1847), though her lowly birth and humble station would not have earned her the appellation of lady in that rigidly stratified society. But in spite of, or perhaps because of, her lowly status, this remarkable woman became one of the most successful fossil collectors of all time. After discovering the world's first ichthyosaur when she was only twelve, she went on to discover the first plesiosaur and the first British pterosaur. As the supplier of many of the fossils the learned gentlemen studied and communicated to their geological circle, she played a central role in the story. However, she was often forced to share center stage with one of the gentlemen of science.

    The fossilists lived in different parts of the country, but they regularly met in London, primarily at the bimonthly meetings of the Geological Society. This learned society was founded in 1807 to acquaint geologists with each other, for "stimulating their zeal," and to communicate new facts. Buckland and Conybeare both joined in 1811; Lyell joined in 1819, Mantell in 1820, and Hawkins in 1832. Darwin became a member in 1836, on returning to England from his world voyage aboard the Beagle . Owen joined the following year. Anning, being a woman, would not have been allowed to join even if she had wanted to, but she was made an honorary member after her death. The geological circle exchanged their ideas through reading and discussing their scientific papers. They dined together, and occasionally visited each other's homes. Some went fossilizing and geologizing together, and some even accompanied one another on Continental excursions. But they did not all get on well together, and there were all the usual rivalries and jealousies that mark our modern human interactions.

    No less extraordinary than the fossilists themselves were the times in which they lived. Their story begins in England, during the late teens of the nineteenth century, and ends just before publication of the Origin of Species . These were times of great political unrest, when the turmoil in France, which did not end with the Revolution, seemed destined to sweep across the English Channel. This was also the time of the Industrial Revolution--the clanking behemoth that rumbled across Britain like a steam locomotive, changing lives and fortunes at a rate unprecedented until our modern age. It was a time, too, when the rich, who alone could afford the luxury of holidays, discovered the restorative benefits of the sea and sea air. Among the fashionable seaside resorts that sprang up along the coast to cater to their needs was Lyme Regis, where Mary Anning lived.

Copyright © 2001 Christopher McGowan. All rights reserved.