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Summer for the Gods

Harvard University Press

Chapter One

DIGGING UP
CONTROVERSY

                              As the scientific world prepared to celebrate the fiftieth anniversary of Charles Darwin's Origin of Species in 1909, an amateur English geologist named Charles Dawson made a momentous find thirty miles from Darwin's country home in southern England. From a laborer digging in a gravel piton a farm near Piltdown Common, Sussex, Dawson received a small fragment of a human cranium's parietal bone. "It was not until some years later, in the autumn of 1911, on a visit to the spot, that I picked up, among the rainwashed spoilheaps of the gravel-pit, another and larger piece belonging to the frontal region of the same skull," Dawson later reported in an article that shook the scientific world. "As I had examined a cast of the Heidelberg jaw, it occurred to me that the proportions of this skull were similar to those of that specimen." This caught his attention. At the time, the Heidelberg jaw represented one of the only two known fossil remains that scientists then attributed to hominid species ancestral to modern humans. Each of these known remains--the jawbone from near Heidelberg, Germany, and a skullcap, three teeth, and a thighbone discovered in Java--had been found during the preceding two decades and remained the subject of intense scientific controversy. The better-known Neanderthal (or Mousterian) "cave men" contributed little to the story of human evolution because they came from a later era, were fully human, and died out. The Piltdown skull, however, could provide the notorious "missing link" in human evolution?

    Dawson now began rummaging through the gravel pit in earnest. After uncovering flint tools and the fossil remains of various prehistoric animals, he took the lot to the paleontologist Arthur Smith Woodward of the British Museum in London. Soon Woodward was in Piltdown with Dawson conducting a systematic excavation of the site. During the summer of 1912, they found more fragments of the Piltdown skull, additional prehistoric animal fossils mixed with human tools, and part of a jawbone with two intact molars. These pieces carried tremendous potential significance. Owing to its size and shape, the cranium clearly came from a hominid. The flint tools reinforced this conclusion. The animal remains and the geology of the site suggested that the skull dated from the Pleistocene epoch, at some point midway between the supposed date of the so-called ape-man of Java and the emergence of modern humans. The jaw, however, appeared to come from a type of ape never known to have lived in Europe, and the teeth were worn down in a human fashion. Pieced together by Woodward, the picture emerged of a new species of extinct hominid that he called Eoanthropus dawsoni, or the "dawn man" of Piltdown.

    Dawson and Woodward unveiled their discovery on December 18, 1912, before a packed house of Britain's scientific elite at the Geological Society of London. "While the skull, indeed, is essentially human, and approaching the lower grade in certain characters of the brain," they explained at the time, "the mandebile appears to be almost precisely that of an ape, with nothing human except the molar teeth." After describing their find in great detail and fitting it into the sequence of other known fossil remains, Dawson and Woodward concluded, "It tends to support the theory that Mousterian man was a degenerate offshoot of early man, and probably became extinct; while surviving man may have arisen directly from the primitive source of which the Piltdown skull provides the first discovered evidence." Sir Arthur Keith, one of the world's leading experts on human antiquity and anatomy, attended the presentation by Dawson and Woodward, and generally concurred in their conclusions, as did the renowned neurologist Grafton Elliot Smith and the famed biologist Boyd Dawkins. Perhaps Dawkins best expressed the collective response of the learned audience when he declared during the discussion period, "The evidence was clear that this discovery revealed a missing link between man and the higher apes."

    Word of the discovery became front-page news throughout the United States, where prominent creationists still publicly denounced the Darwinian theory of human evolution. Relying on a special same-day cable transcript, the New York Times published a summary of Dawson and Woodward's initial presentation within hours of the event. "Paleolithic Skull Is a Missing Link," the Times headline proclaimed, "Bones Probably Those of a Direct Ancestor of Modern Man." A day later, the Times followed up with a telegraphic interview of Woodward. "Hitherto the nearest approach to a species from which we might have been said to descend that had been discovered was the cave-man," Woodward observed in this interview, "but the authorities constantly asserted that we did not spring direct from the cave-man. Where, then, was the missing link in the chain of our evolution? To me, at any rate, the answer lies in the Piltdown skull, for we came directly from a species almost entirely ape." Other American newspapers carried similar reports.

    The New York Times concluded its coverage of the Piltdown discovery with an extended, page-one summary of the episode, appearing in its next Sunday edition. "Darwin Theory Is Proved True," proclaimed the banner headline. "English Scientists Say the Skull Found in Sussex Establishes Human Descent from Apes." This article reprinted Keith's observation that the discovery "gives us a stage in the evolution of man which we have only imagined since Darwin propounded the theory." Yet an editorial entitled "Simian Man" appearing in that same Sunday edition cautioned readers, "Those who have read the cable dispatches to The Times describing the oldest human skull ... must not confuse this ancient man with the 'missing link' or with the ancestry of the present human race. Darwin thought that man was descended from apes, but he searched in vain for the half-man, half-ape." Although the British scientists quoted in those dispatches clearly saw the new fossil as filling a missing link in the record of human evolution, the Times editorial cites their classification of the Piltdown hominid as a distinct species to support the conclusion that "he was no forebear of our Adam."

    This peculiar editorial disavowing a scientific news report reflected the divided mind of the American public, during the years leading up to the Scopes trial, regarding the controversial topic of human evolution. Of course, no single fossil discovery could prove the Darwinian theory of human evolution. As the New York Times editorial suggested, evidence that a "simian man" walked the earth in the Pleistocene epoch does not conclusively establish a simian ancestry for modern humans. Yet it fit into a larger pattern. During the first quarter of the twentieth century, scientists in western Europe and the United States accumulated an increasingly persuasive body of evidence supporting a Darwinian view of human origins, and the American people began to take notice. These scientific developments helped set the stage in the early 1920s for a massive crusade by fundamentalists against teaching evolution in public schools, which culminated in the 1925 trial of John Scopes.

The theory that current living species evolved from preexisting species had been around for a long time. More than a century earlier, a well-known French naturalist, the Chevalier de Lamarck, had proposed a theory of progressive evolutionary development based on vital forces within living things and the inheritance of acquired characteristics. Lamarck viewed the various biological species as arranged in an ascending hierarchy from the simplest to the most complex, reflecting a historical pattern of development. Vital forces within living entities prompted their development, allowing each generation to progress beyond the level of complexity of its ancestors. The use or disuse of organs in response to changed environmental conditions further propelled evolutionary progress, according to Lamarck, as living entities passed their acquired characteristics on to their offspring. The giraffe's neck remains the most famous example of this process. As vegetation became scarcer in their habitat, Lamarck hypothesized, the ancestors of the present-day giraffe stretched their necks to eat the remaining leaves high on trees. The next generation inherited the longer necks and stretched them still further, until a new species of long-neck giraffe evolved.

    Although early nineteenth-century scientists generally did not accept Lamarck's ideas on evolution and held to the creationist concept that each biological species remained fixed over time, many of them did embrace the bold theories of Lamarck's rival, Georges Cuvier. As curator of vertebrate fossils at the prestigious French Museum of Natural History, Cuvier was the first Enlightenment-era naturalist forced to come to terms with the increasingly complex fossil record then being unearthed by scientific expeditions. This research drove him to acknowledge that the earth had a very long geologic history, far longer than suggested by a literal interpretation of the account in Genesis, and that countless biological species had appeared and become extinct during that long history, despite the traditional scientific and religious view that all species continued over time. Sudden breaks that appeared in the fossil record in which one characteristic group abruptly replaced an earlier one with few transitional forms, coupled with a conviction that living species were too complex to evolve, led Cuvier to conclude that great catastrophes such as worldwide floods or ice ages punctuated geologic history into a series of distinct epochs. Each catastrophe wiped out most or all living things, leaving the earth to repopulate through migration by the few survivors, as Cuvier at first supposed, or new creations of biological species, as later naturalists concluded after wider exploration found no ancient source for modern animals.

    Cuvier's theories quickly came to dominate the geological thinking of the day. Some secular scientists in that era of romanticism and transcendentalism attributed the successive new creations of species to a vital force within nature. Christian geologists, in contrast, saw the hand of God directly at work in these creative acts. Both groups, however, accepted a long geologic history and the progressive appearance of new life forms. For Christians, this posed a conflict with the account in Genesis, which declared that God formed the heavens, the earth, and all kinds of living things in six days, culminating in the creation of Adam and Eve as the forebears of all human beings. In the fifteenth century, the scholarly archbishop James Ussher used internal evidence within Genesis to fix the year of creation at 4004 B.C. Even if they did not adopt this precise year, many later Christians accepted a similar time frame for the creation. In America during the middle part of the nineteenth century, such leading geologists as Amherst College president Edward Hitchcock and Yale's James D. Dana reconciled contemporary geological opinion with their traditional religious beliefs by interpreting the biblical days of creation as symbolizing geologic ages or, alternatively, by positing a gap in the Genesis account. Nineteenth-century Protestants, including many with decidedly conservative views of scriptural authority, readily accepted such accommodations of science and religion. Even the Scofield Reference Bible, which profoundly influenced the development of modern fundamentalism around the turn of the twentieth century, incorporated the "gap theory" into its explanation of Genesis and referred to the "day/age theory" in a footnote."

    The advent of Darwinism presented a far greater threat to Christians than simply a long geological history and the progressive appearance of species. When Darwin's Origin of Species first appeared in 1859, few scientists accepted the concept of organic evolution. Within two decades, however, even a hostile church journal could identify only two working American naturalists who still opposed it. Darwin's eloquent presentation of evidence for evolutionary development drawn from careful observation of nature certainly contributed to this turnabout, but he proposed also that a "survival of the fittest" process of natural selection drove evolutionary change rather than the benign process of individual adaptation envisioned by Lamarck. Although Darwin always maintained a place for Lamarckian-type mechanisms within his theory of evolution, his concept of natural selection became widely identified as the central feature of Darwinism.

The high school textbook at issue in the Scopes trial, George William Hunter's A Civic Biology, summarized Darwin's alternative evolutionary mechanism in a section entitled "Charles Darwin and Natural Selection." Darwin observed that individual plants and animals tended to vary slightly from their ancestors, Hunter noted. "In nature, the variations which best fitted a plant or animal for life in its environment were the ones which were handed down because those having variations which were not fitted for life in that particular environment would die," Hunter wrote. "Thus nature seized upon favorable variations and after a time, as the descendants of each of these individuals also tended to vary, a new species of plant or animal, fitted for the place it had to live in, would be gradually evolved." In short, as Hunter explained, Darwin postulated new species "arising from very slight variations, continuing during long periods of years." This mechanism attributed these all-important variations to random individual differences inborn in the offspring rather than to Lamarckian vital forces or acquired characteristics. "Species have been modified, during a long course of descent," Darwin concluded in the Origin of Species, "chiefly through the natural selection of numerous successive, slight, favorable variations."

    Darwin's account of random variations, coupled with his survival-of-the-fittest selection process, posed a critical problem for many Christians who retained a teleological view of nature. In 1860, Darwin anticipated this problem in an exchange with the Harvard botanist Asa Gray, a devout Protestant. Christians long maintained that the harmonious structure of the physical universe and each living thing reflected intelligent design by a creator, and thereby contributed evidence of the existence and loving character of God. Gray, who had arranged the initial publication of the Origin of Species in the United States, asked Darwin about the book's theological implications. "I had no intention to write atheistically," Darwin replied. "But I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice." For some conservative theologians and pious scientists, this represented the ultimate challenge of Darwinism to a Christian world view: Beneficial variation was random and natural selection was cruel. If nature reflected the character of its creator, then the God of a Darwinian world acted randomly and cruelly. Darwin could not accept such a God, and became an agnostic. Others recognized the magnitude of the issue.

    Battle lines formed quickly. The self-proclaimed "gladiator-general" of Darwinism, English naturalist T. H. Huxley, claimed to take up the banner for science. Anticipating religious opposition to Darwin's ideas, the agnostic Huxley--who embraced the theory of evolution as a naturalistic rebuttal to the claims of Christianity--wrote to Darwin shortly before publication of Origin of Species, "I am sharpening up my claws and beak in readiness." Following publication, Huxley aggressively championed the cause in countless public debates and popular articles, clashing with such religiously motivated critics of Darwinism as Oxford bishop Samuel Wilberforce and British prime minister William Gladstone. "Whether astronomy and geology can or cannot be made to agree with ... Genesis," Huxley wrote in a typical passage, "are matters of comparatively small moment in the face of the impassable gulf between the anthropomorphism (however refined) of theology and the passionless impersonality ... which science shows everywhere underlying the thin veil of phenomena. Here seems to me to be the great gulf fixed between science and theology." Counterattacking in the name of religion, Princeton theologian Charles Hodge took the lead in challenging Darwinism. His provocatively titled 1874 book What is Darwinism? presented a tightly reasoned argument that led to the inevitable answer: "It is atheism [and] utterly inconsistent with the Scriptures." For Hodge, Darwin's "denial of design in nature is virtually the denial of God."

    Hodge and some other church leaders raised an alarm against teaching evolution, particularly within seminaries and denominational colleges, but scientific developments temporarily quieted the conflict. In the 1870s and 1880s, Darwinism faced a host of technical challenges. The best evidence from the physical sciences suggested that the solar system was not old enough for slight, random variations in one or more organisms to produce the current array of biological species, much less to generate life from nonlife. Further, without a means to preserve inherited differences, such variations did not lead anywhere. Like most naturalists working before the acceptance of Mendelian genetics, Darwin believed that the inherited traits of an offspring consisted of a blending of those possessed by its parents. Slight, random variation in an individual--no matter how much it helped that animal or plant survive--quickly would be swamped as that individual bred with others of its species, so that gradually each succeeding generation would lose its distinctiveness. Even if individuals with a particularly beneficial trait mated solely with those possessing the same trait--such as happens in the breeding of domesticated animals--their offspring then simply would tend to preserve that trait, not exceed it. If organic evolution occurred (and by 1880 most naturalists believed that it did), then some mechanism must accelerate and direct variation; for some devout Christians, this left a role for God.

    Two alternative theories of evolution were discussed widely among American and European scientists during the final third of the nineteenth century. Ever the traditional Christian, Asa Gray proposed a theory of theistic evolution in which God channeled variations into a pattern of progressive development. The renowned British scientists Charles Lyell, Richard Owen, and St. George Mivart toyed with similar ideas. For some, this offered a way to reconcile religious faith with evolutionary theory and science. Other naturalists, led in the United States by the likes of Joseph LeConte, Clarence King, and Edward Drinker Cope, revived Lamarckian-type explanations to account for the speed and direction of evolution. According to these late-nineteenth-century naturalists--some of whom went so far as to call themselves "neo-Lamarckians"--indwelling vital forces pulled each species forward toward increasing complexity, while each individual pushed in the same direction through the use and disuse of organs in response to shared environmental conditions. Variations became purposeful and natural selection marginalized.

    These alternative theories of evolution might not fit neatly with traditional Christian doctrines, but they certainly could be spiritual. In a lecture to Yale seminarians, for example, Gray declared that with evolution, "the forms and species, in all their variety, are not mere ends in themselves, but the whole a series of means and ends, in the contemplation of which we may obtain higher and more comprehensive, and perhaps worthier, as well as more consistent, views of design in Nature than heretofore." Similarly, the neo-Lamarckians' principal journal, American Naturalist, professed a goal of "illustrating the wisdom and goodness of the Creator." LeConte defined the "laws of evolution" as "nought else than the mode of operation of the ... divine energy in originating and developing the cosmos." King denounced natural selection: "A mere Malthusian struggle was not the author and finisher of evolution; but that He who brought to bear that mysterious energy we call life upon primeval matter bestowed at the same time a power of development by change." A Quaker turned Unitarian, Cope concluded in his Theology of Evolution, "The Neo-Lamarckian philosophy is entirely subversive to atheism." Conservative Christians might disagree with these views on various points of doctrine, but few raised loud objections, and many liberal Christians wholly embraced an evolutionary creed.

    Neo-Lamarckianism and other non-Darwinian forms of evolutionary thought swept the scientific community, particularly in the United States. "From the high point of the 1870s and 1880s, when 'Darwinism' had become virtually synonymous with evolution itself, the selection theory had slipped in popularity to such an extent that by 1900 its opponents were convinced it would never recover," the historian Peter J. Bowler observed. "Evolution itself remained unquestioned, but an increasing number of biologists preferred mechanisms other than selection to explain how it occurred." Even Darwin granted an ever larger role to Lamarckian explanations for variation in later editions of the Origin of Species. "The fair truth is that Darwinian selection theories," Stanford zoologist Vernon L. Kellogg concluded in 1907, "stand to-day seriously discredited in the biological world."

    With the "eclipse of Darwinism," as T. H. Huxley's grandson Julian later referred to this period in the history of biology, many conservative Christians toned down their rhetoric. "I do not carry the doctrine of evolution as truth as some do," William Jennings Bryan assured audiences around the turn of the century. But he quickly added, "I do not mean to find fault with you if you want to accept the theory; all I mean to say is that while you may trace your ancestry back to the monkey if you find pleasure or pride in doing so, you shall not connect me with your family tree without more evidence than has yet been provided." Apparently the evidence satisfied such highly orthodox Protestant theologians as Princeton's James McCosh and Rochester seminary president A. H. Strong, who now took the position that Christians could accept evolution as, to use Strong's words, "the method of divine intelligence" in creation.

    A similarly conciliatory tone sounded in some early essays in The Fundamentals, a series of popular booklets published between 1905 and 1915 that helped define the tenets of Protestant fundamentalism. Princeton theologian B. B. Warfield contributed an article to the first volume of this series about the same time as he publicly endorsed theistic evolution as a tenable theory of the "divine procedure in creating man." The theologian James Orr allowed his favorable views on organic evolution to spill over into his four essays for The Fundamentals. Earlier he had written, "Assume God--as many devout evolutionists do--to be immanent in the evolutionary process, and His intelligence and purpose to be expressed in it; then evolution, so far from conflicting with theism, may become a new and heightened form of the theistic argument." In The Fundamentals, Orr added, "Much of the difficulty on this subject has arisen from the unwarrantable confusion or identification of evolution with Darwinism." Now that the "insufficiency of 'natural selection'" has been widely recognized by scientists, Orr asserted that evolution was "coming to be recognized as but a new name for 'creation.'" Based on this endorsement for theistic evolution, Orr could confidently proclaim, "Here, again, the Bible and science are felt in harmony."

    By the turn of the century, secular historians and essayists rather than theologians and scientists were largely responsible for keeping alive the public perception of hostility between Christians and evolutionists. During the last third of the nineteenth century, two academicians from New York, John William Draper and Andrew Dickson White, wrote enormously popular but highly biased histories of the relationship between science and religion. Draper described his History of the Conflict Between Religion and Science as "a narrative of the conflict of two contending powers, the expansive force of the human intellect on one side, and the compression arising from traditionary faith and human interests on the other." White opened his Warfare of Science with the sentence, "I propose to present an outline of the great, sacred struggle for the liberty of science--a struggle which has lasted for so many centuries, and which yet continues." He later fleshed out this brief book into a massive, two-volume A History of the Warfare of Science with Theology in Christendom. These books recounted Roman Catholic attacks on Copernican astronomy, including the seventeenth-century trial of Galileo and execution of Giordano Bruno, and fostered the impression that religious critics of Darwinism threatened to rekindle the Inquisition. They neither reported the growing harmony between theologians and evolutionists nor noted that most great physical scientists of the period, from John Dalton and Michael Faraday to Lord Kelvin and James Clerk Maxwell, were devout Christians. Instead, as James Orr complained in The Fundamentals about these books, "Science and Christianity are pitted against each other. Their interests are held to be antagonistic."

    This contentious view of science and religion gained a wide following among secular scholars during the early twentieth century and stiffened their resolve to defy Bryan's antievolution crusade during the 1920s. "Andrew D. White's Warfare of Science with Theology is responsible for much of their thinking about religious bigotry and intolerance, and they are ready to join in smiting the Infamous," famed Vanderbilt University humanist Edwin Mires observed of his fellow academics in an address to the Association of American Colleges in 1924. "In other words, college professors are like most human beings in not being able to react to one extreme without going to the other." During the years leading up to the Scopes trial, this reaction inspired an outpouring of academic books, articles, and essays discussing the conflict between science and religion, with an increasing focus on the seemingly pivotal issue of Darwinism. During the first decade of the century, for example, one commentator wrote that Darwin's theory "seemed to promise the greatest victory ever yet won by science over theology." To another, it "constituted the final and irresistible onslaught of science on the old view as to the nature of Biblical authority." In 1922, Piltdown fossil expert Arthur Keith wrote of Darwin and Huxley, "They made it possible for us men of to-day to pursue our studies without persecution--without being subject to the contumely of Church dignitaries."

    By 1925, the warfare model of science and religion had become ingrained into the received wisdom of many secular Americans. Clarence Darrow imbibed it as a child in Kinsman, Ohio, where his fiercely anticlerical father eagerly read Draper, Huxley, and Darwin, and made sure that his son did too? As a Chicago lawyer and politician in the 1890s, Darrow quoted Draper and White in his public addresses and denounced Christianity as a "slave religion" that "sought to strangle heresy by building fires around heretics." Similar views characterized Scopes's other defenders. For example, en route to Dayton, defense cocounsel Arthur Garfield Hays told reporters, "Of all the books I have read for this trial, the 'Warfare Between Science and Religion [sic],' by Prof. White, is, to my mind, one of the most interesting and readable." He quoted from this book in the course of his legal argument in Dayton and distributed it to at least some of the people that he met there. The zoologist Winterton C. Curtis, who served as an expert witness for Scopes, did not need a copy--he knew the story by heart. "I remembered how, as a college student in the mid-nineties, I had almost wished that I had been born twenty years earlier and had participated in the Thirty Year War [between Darwinists and Christians], when the fighting was really hot," Curtis later recalled. "When, in the second decade of the present century, some of my former students, who had become teachers, began to report the restrictions laid upon them in high schools and in some denominational colleges, I ... [assumed] an active part in the defense of evolution."

    As Curtis suggested, the warfare between fundamentalists and evolutionists revived by the 1920s, along with the fortunes of Darwinism. Darwin historian James R. Moore described this renewed controversy: "Fifty years it had taken for the teaching of evolution to filter into the high schools, for the high schools to reach the people, and for the people--those, at any rate, who became militant Fundamentalists--to belong to a generation who could not remember the evangelical evolutionists among its ancestors." Moore identified two different causes for the timing of the antievolution crusade here. First, Darwinism did not become a fighting matter for many fundamentalists until it began to influence their children's education in the twenties. Second, Christian biologists at that time could not so readily step in, as they had earlier, to soften evolution's impact on religious belief. Largely due to developments in experimental genetics, biologists increasingly accepted random, inborn variation as the driving force for evolutionary change and rejected the Lamarckian-type explanations that diminished the role of natural selection. Both were significant causes.

    Evolutionary theory did not suddenly appear in American high school education at the time of the antievolution crusade; it had been incorporated into leading textbooks during the late nineteenth century, bur with a theistic or Lamarckian twist that reflected prevailing scientific opinion. Asa Gray's popular text, for example, explained how evolutionary relationships showed that biological species "are all part of one system, realizations in nature, as we may affirm, of the conception of One Mind." Joseph LeConte organized his 1884 high school textbook around the concept of evolution without ever mentioning natural selection. Purposeful non-Darwinian mechanisms dispensed with the need for chance variations and a naturalistic struggle for survival.

    Textbooks typically became more Darwinian in the new century, however, especially after the newly organized field of biology began to replace separate courses on botany and zoology in the high school curriculum, One representative biology text featured a picture of Darwin and a subchapter titled "The Struggle for Existence and Its Effects." Another hailed Darwin for discovering "the laws of life," including the concept of organic evolution through natural selection. Hunter's Civic Biology, the best-selling text in the field, credited Darwin for "the proofs of the theory on which we to-day base the progress of the world." This view of progress was decidedly anthropocentric and heavily laced with the scientific racism of the day. According to Hunter, "simple forms of life on the earth slowly and gradually gave rise to those more complex." Humans appeared as a progressive result of this evolutionary process, with the Caucasian race being "finally, the highest type of all." Overall, Darwinism did not feature prominently in Hunter's books or in other early twentieth century biology texts that stressed practical problems, but the concept of organic evolution pervaded the whole of them.

    Darwinian concepts in public secondary education touched more families, and more fundamentalists, as the new century unfolded. Relatively few American teenagers attended high school during the nineteenth century, and nearly none did so in the rural South, where such schools rarely existed and local authorities did not compel student attendance. The situation changed dramatically after the turn of the century. Census figures tell the story. The number of pupils enrolled in American high schools lept from about 200,000 in 1890, when the federal government began collecting these figures, to nearly two million in 1920. Tennessee followed this national trend, with its high school population rising from less than 10,000 in 1910 to more than 50,000 at the time of the Scopes trial in 1925. This increase resulted in part from tougher Progressive-era school attendance laws that forced more teenagers to go to school, and followed also from greater access to secondary education, as the number of public high schools increased dramatically during the early part of the century. Commenting on this trend with respect to Tennessee, Governor Austin Peay--who signed the state's antievolution bill into law--boasted in his 1925 inaugural address, "High schools have sprung up throughout the state which are the pride of their communities." This was certainly true for Dayton, site of that year's Scopes trial, which opened its first public high school in 1906. These new schools inevitably included Darwinian concepts in their biological classes, in line with modern developments in American scientific thought.

    Hunter's Civic Biology reflected some of these scientific developments by including sections on both natural selection and genetics. In designing the new biology curriculum for secondary schools, Hunter and his colleagues at New York's DeWitt Clinton High School worked closely with educators at nearby Columbia University. The Columbia faculty included many leading educators at the university's famed Teachers College and America's foremost geneticist, Thomas Hunt Morgan. While Hunter sought the advice of education experts in shaping the contents of biology instruction, one of his closest colleagues earned a doctorate under Morgan, then in the process of laying the foundations of modern genetics.

    Morgan began his groundbreaking research at the turn of the century as an opponent of both gradual Darwinian natural selection and static Mendelian genetics. He favored an alternative theory of rapid evolution by the occurrence and hereditary transmission of inborn mutations. Through experiments with generations of fruit flies, Morgan came to recognize that the inheritance of mutations followed a Mendelian pattern that could provide the basis for a Darwinian form of evolution. Under Mendelianism, he reasoned, even slight mutations in an individual plant or animal would survive in the population and could succeed by means of natural selection. "Evolution has taken place by the incorporation into the race of those mutations that are beneficial to the life and reproduction of the organism," Morgan wrote in 1916. "Natural selection as here defined means both the increase in the number of individuals that results after a beneficial mutation has occurred (owing to the ability of living matter to propagate) and also that this preponderance of certain kinds of individuals in the population makes some further results [in the same direction] more probable than others."

    Morgan never fully accepted the sufficiency of slight, random variations to account for the emergence of new species. He continued to rely on mutations to fuel evolution, with natural selection acting as a sieve, and rejected, as he later wrote, "Darwin's postulate that the individual variations, everywhere present, furnished the raw material for evolution." It took a generation of research by population geneticists, biometricians, traditional Mendelianists, and field naturalists to construct the modern neo-Darwinian synthesis that today dominates scientific thought. By the 1920s, however, the Darwinian mechanisms of random variation and natural selection were returning to center stage in biology. Most fundamentalists never recognized these subtle developments within evolutionary theory and simply rejected all forms of evolution as contrary to a literal reading of scripture, yet for conservative Christians troubled more by the implications of random variation and natural selection than by the general concept of organic evolution, and Bryan fell into this camp, the ground for accommodation was shrinking. And everyone engaged with the issue could understand such bold proclamations as those of the popular science writer A. E. Wiggam, who commented on the Scopes trial, "Mr. Bryan did not even know that evolution takes place ... in the hereditary units called 'genes.' ... Morgan and his students ... have adduced evidence that these genes are themselves the subject of change. And if these genes can be proved to change ... then, the case for evolution is absolutely won."

    As the example of Morgan illustrates, Darwinism revived gradually. Biologists continued to defend a variety of evolutionary mechanisms, including Lamarckian ones, for a generation; the modern neo-Darwinian synthesis did not fully emerge until the 1940s, but the lack of consensus simply emboldened the antievolution crusaders. Bryan and some other crusader leaders mastered the technique of using scientific arguments against Darwinian mechanisms to attack the theory of organic evolution, infuriating evolutionary biologists. After Bryan asserted in a 1922 essay published by the New York Times that "natural selection is being increasingly discredited by scientists," American Museum of Natural History president Henry Fairfield Osborn, a renowned paleontologist and science popularizer, demanded equal time. "I am deeply impressed with the fact that he has familiarized himself with many of the debatable points in Darwin's opinions," Osborn offered. "Mr. Bryan, who is an experienced politician, and who has known politicians to disagree, should not be surprised or misled when naturalists disagree in matters of opinion. No living naturalist, however, so far as I know, differs as to the immutable truth of evolution ... of all the extinct and existing forms of life, including man, from an original and single cellular state."

    In a similar appeal to the public, Morgan observed, "It is the uncertainty concerning the factors of evolution that has given the opponents of the theory of evolution an opportunity to attack the theory itself." He characterized natural selection as "a theory within a theory" of evolution. "It is an easy task," Morgan warned, "for the anti-evolutionists, by pointing out the conflict of opinion concerning the causes of evolution, to confuse this issue with that involving only the interpretation of the factual evidence showing that evolution has taken place." Neither Osborn nor Morgan accepted natural selection of slight, random variations as the sole mechanism for evolution, but both took their stand against the antievolutionist crusade.

    A further "scientific" development spurred Bryan and some other antievolutionists. Many Americans associated Darwinian natural selection, as it applied to people, with a survival-of-the-fittest mentality that justified laissez-faire capitalism, imperialism, and militarism. Decades before the crusade, for example, Andrew Carnegie and John D. Rockefeller, Sr., claimed this as justification for their cutthroat business practices. Bryan, who built his political career on denouncing the excesses of capitalism and militarism, dismissed Darwinism in 1904 as "the merciless law by which the strong crowd out and kill off the weak." During the years immediately preceding the antievolution crusade, a scientific-sounding form of these social doctrines gained widespread public attention under the name eugenics. In one of his popular textbooks, Hunter defined this term as "the science of improving the human race by better heredity." This new "science" was first proposed by Darwin's cousin, the English scholar Francis Galton, in the 1860s as a means to accelerate beneficial human evolution. The idea attracted few supporters until the turn of the century, when developments in Mendelian genetics made it appear plausible. British eugenicists always associated their cause with Darwin, especially after Darwin's son Leonard assumed presidency of the national Eugenics Education Society. Hence in England, for example, a passion to prove eugenics inspired the evolutionary biologist Ronald A. Fisher to pursue research that, beginning in 1918, helped establish the modern neo-Darwinian synthesis.

    In America, many evolutionary biologists embraced eugenics early in the century, but the public campaign to impose eugenic restrictions on reproduction peaked in the twenties. As a result, the eugenics movement coincided with the antievolution crusade in many states. Typically justifying their actions on the basis of evolutionary biology and genetics, by 1935, thirty-five stares enacted laws to compel the sexual segregation and sterilization of certain persons viewed as eugenically unfit, particularly the mentally ill and retarded, habitual criminals, and epileptics. "If such people were lower animals, we would probably kill them off to prevent them from spreading," Hunter explained in his Civic Biology. "Humanity will not allow this, but we do have the remedy of separating the sexes in asylums or other places and in various ways preventing intermarriage and the possibility of perpetuating such a low and degenerate race."

    Some antievolutionists denounced eugenics as the damnable consequence of Darwinian thinking: First assume that humans evolved from beasts and then breed them like cattle. Bryan decried the entire program as "brutal" and at Dayton offered it as a reason for not teaching evolution. Everywhere the public debate over eugenics colored people's thinking about the theory of human evolution. Popular evangelist Billy Sunday, for example, repeatedly linked eugenics with teaching evolution during his 1925 Memphis crusade, which coincided with legislative consideration of the Tennessee antievolution bill. "Let your scientific consolation enter a room where the mother has lost her child. Try your doctrine of the survival of the fittest," Sunday proclaimed at one point. "And when you have gotten through with your scientific, philosophical, psychological, eugenic, social service, evolution, protoplasm and fortuitous concurrence of atoms, if she is not crazed by it, I will go to her and after one-half hour of prayer and the reading of the Scripture promises, the tears will be wiped away." Such prominent eugenicists as A. E. Wiggam recognized a tie between antievolutionism and opposition to eugenics. At the outset of the antievolution crusade, he criticized Sunday and Bryan for not supporting eugenics. Later on, he lamented that "until we can convince the common man of the fact of evolution ... I fear we cannot convince him of the profound ethical and religious significance of the thing we call eugenics."

    As much as fundamentalists deplored the social and religious consequences, however, the scientific evidence for human evolution kept accumulating. Late in the summer of 1924, a South African university student brought a fossilized skull to her anatomy professor, Raymond A. Dart. He identified the skull as coming from an ancient baboon and was fascinated by the round hole in its braincase. He promptly sought more specimens from the source of the find, a limestone quarry at Taungs. Two crates of fossils arrived later that fall. "As soon as I removed the lid a thrill of excitement shot through me. On the very top of the rock heap was what was undoubtedly an endocranial cast or mold of the interior of a skull," Dart later recalled. "I knew at a glance that what lay in my hand was no ordinary anthropoidal brain.

    Dart rushed into print with his discovery. "Unlike [Java man], it does not represent an ape-like man, a caricature of a precocious hominid failure, but a creature well advanced beyond modern anthropoids in just those characteristics, facial and cerebral, which are to be anticipated in an extinct link between man and his simian ancestor," Dart announced in a February 1925 scientific publication. "At the same time, it is equally evident that a creature with anthropoid brain capacity ... is no true man. It is therefore logically regarded as a manlike ape." The Scottish anthropologist Robert Broon noted, "If an attempt is made to reconstruct the adult skull it is surprising how near it appears to come to [Java man]--differing only in the somewhat smaller brain and less erect attitude. While nearer to the anthropoid ape than man, it seems to be the forerunner of such a type as [Piltdown man], which may be regarded as the earliest human variety." Arthur Keith was more cautious, to which Dart replied, "If any errors have been made they are all on the conservative (ape) side and it is certain that subsequent work will serve only to emphasise the human characteristics."

    Dart identified one particular human characteristic of the Taungs man-ape that would especially trouble Bryan and the antievolutionists: In trying to deduce how the creature could have survived on the dry plains of the Transvaal, Dart remembered the round hole in the baboon skull from the same site. "Was it possible that the opening had been made by another creature to extract its brain for food?" he asked himself. "Did this ape with the big brain catch and eat baboons? If so it must have been very clever." Such reasoning crept into Dart's initial publication. Paleontologists had mistakenly looked for the missing link in "the luxuriant forests of the tropical belts," he wrote. "For the production of man a different apprenticeship was needed to sharpen the wits and quicken the higher manifestations of intellect .... Southern Africa, by providing a vast open country with occasional wooded belts and a relative scarcity of water, together with a fierce and bitter mammalian competition, furnished a laboratory such as was essential to this penultimate phase of human evolution." In short, humans evolved through hunting. As Bryan had warned, Darwin's dreadful law of hate was replacing the Bible's divine law of love as the origin of humanity.

    The Johannesburg Star scooped the story four days before Dart's official announcement. The news spread fast. A front-page article in the next morning's edition of the New York Times proclaimed, "New-Found Fossilized Skull May Be That of Missing Link." Other newspapers followed suit. A popular magazine removed God from the picture altogether in its poetic rendition of events:

Here lies a man, who was an ape.
Nature, grown weary of his shape,
Conceived and carried out the plan
By which the ape is now the man.

    Many conservative Christians were openly hostile. A letter to the editor in the London Times appealed to Dart: "Man stop and think. You ... have become one of the Devil's best arguments in sending souls to grope in the darkness." Bryan dismissed all the fossil remains of early humanoids as inconclusive and inconsequential. Many other antievolutionists did the same. Less than two months after Dart's announcement, a New York newspaper reported, "Professor Dart's theory that the Taungs skull is a missing link has evidently not convinced the legislature of Tennessee, the governor of which state has signed an 'Anti-Evolution' Bill which forbids the teaching ... that man is descended from lower order of animals." Plaster models of the Taungs skull and Piltdown fossils soon appeared as evidence for the defense in Scopes's legal challenge to that new law.

Continues...

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Excerpted from Summer for the Gods by Edward J. Larson Copyright © 1998 by Edward J. Larson. Excerpted by permission.
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