The First Americans Read online

  Louis Agassiz (left) and Benjamin Pierce.

  The origin of glacial theory has its own historical “stratigraphy,” and Agassiz lies near its earliest stratum, but there were others below him. He was the first to publish a major explication of the role glaciers might have played in creating the European landscape, but that is because he was a quick study rather than the first to put it all together. When he began tolook into glacial features in 1836, he was bent on proving the then-prevalent notion that at some time in the past, icebergs had been bred in the far north, floated southward, and dropped the big boulders called “erratics” here and there (because they were thought to have been laid down by melting icebergs that drifted south, some glacial deposits are still called “drift”). A few field trips with other naturalists changed Agassiz's mind, and he began talking up the idea of glacial expansion and contraction.

  But others had gotten to that point earlier than he. One was a less well known mining engineer named Johann von Charpentier of Saxony. Char-pentier simply couldn't buy the idea that floods or icebergs had been the moving force behind the big boulders in the Rhône Valley and elsewhere in Europe. He began looking into the subject in 1834, two years ahead of Agassiz, but published his account, Essai sur les glaciers, only in 1841. In it he graciously gave credit to yet an earlier thinker on such matters, a peasant he had met while out on a mountain one day studying a large granite boulder. The peasant allowed as how there were plenty of boulders like that on the mountain but said they had come from elsewhere. When Charpentierasked how the boulder could have gotten there, the man replied that the glacier had brought them when long ago it had extended much farther. He went on to explain why water could not have been the vehicle. Charpentier wrote:

  This good man would never have dreamed that I was carrying in my pocket a manuscript in favor of his hypothesis. He was greatly astonished when he saw how pleased I was by his geological explanation, and when I gave him money to drink to the memory of the ancient glacier and to the preservation of the boulder.

  Glacial erratic left by the retreat of the Ross Ice Shelf at Cape Crozier, Antarctica.

  In any event, Charpentier, who was bitter at being scooped by Agassiz, went on to slip below the radar of most histories of science, while Agassiz promoted glacial theory with exuberance and great accumulation of data against the still widely held diluvian theory of Noah's Flood. There were plenty of reasons, Agassiz thought, including the advance of glaciers across the landscape, to render species of plants and animals extinct, though he would nevertheless continue till death to believe in divine intervention in the creation of new species, as opposed to Darwinian natural selection.

  But credit for the understanding that much of the world was once covered by ice goes back yet further than Charpentier or his rural sage! The great German poet, dramatist, and natural philosopher Johann von Goethe had earlier concluded that there must have been an “epoch of great cold,” and peasants in the Alps had long figured that the glaciers above them had once been more extensive. One of these, J. P. Perraudin, communicated this notion to a Swiss civil engineer as early as 1815, and by 1824 a Norwegian scientist had reached the same conclusion. But all this concerned only local glaciers. It fell in 1832 to a German professor, A. Bernhardi, to infer that glacial ice from the far north had once extended as far south across Europe as Germany. (He also postulated a polar ice cap in the north that we now know doesn't exist, though the phrase continues in use.) Agassiz had the advantage of being a remarkably clear and forceful expositor of science, which is why he got the credit in his day and, in many accounts, still does.

  FOSSILS, FLOODS, ICE

  Glaciers were soon under suspicion as murderers. Until the glaciers were discovered, it had been the Flood that was taken as the force that had wiped out all the big fossil animals that had been turning up for more than a century, many of which naturalists recognized as creatures that no longer dwelled upon the earth. It had taken a bit of time for people to recognize that species of animals could indeed go extinct; such a thought was taken as something of a slur on the Deity's planning. Nevertheless, the bones of huge mammals did turn up in places where living versions were no longer seen—in either Europe or America—and they needed to be accounted for.

  One of the first speculations about the nature of the oversized fauna of America was made by Thomas Jefferson, who, upon laying eyes on a huge claw of an unknown animal found in western Virginia, assumed it was that of an enormous catlike carnivore. He called it Megalonix (“giant claw”) in a 1799 paper in the Transactions of the American Philosophical Society— the first and the last scientific paper ever delivered by a sitting American vice president. (It later turned out to be the claw of a giant ground sloth, named Megalonyx in Jefferson's honor in 1822.)

  Earlier finds of the fossil bones of giant animals were treated more fancifully. In 1706, the governor of Massachusetts wrote to that fire-breathing preacher and scourge of the sinful, Cotton Mather, about a number of bones and a large tooth he had been given by a man who had discovered them near the Hudson River. The tooth, half a foot long and weighing two pounds, looked for all the world like a human eyetooth, and the governor opined in his letter that it was the remains of one or the other race of giants mentioned in the Bible. It could not, he said, be an elephant tooth. As the decades went by, the Russian czar Peter the Great took an interest in such remains, receiving a mammoth tusk from Siberia and encouraging others to find a whole skeleton of the animal. In fact, Peter the Great had an almost ghoulish interest in remains of all sorts: his storeroom contained stuffed humans (especially hairy ones), the remains of Siamese twins, and all sorts of specimens of which the mammoth tusk was hardly the mostbizarre. In 1766, Benjamin Franklin received a collection of mastodon bones and guessed that the teeth belonged to a meat eater, but he later changed his mind: the teeth could just as easily have been useful for chewing branches. While this was a good guess, more insightful was Franklin's opinion that the bones (found in Ohio) came from a region too cold for modern elephants. This led him to suggest that the climate of North America must have been altered at some time, perhaps by a shift in the earth's axis.

  By this time in Europe, many students of natural history had begun to realize that the earth had to be a much older place than a literal reading of the Bible permitted. The great French naturalist and writer Georges Buffon popularized the idea that the 6,000-odd years of history referred only to human history. Prior to the arrival of people and the modern form of the earth, much of a dynamic nature had taken place: theologians could see good sense in the notion that the hand of divine providence might well have spent a good deal of time preparing the earth for God's children. Still, however, the devout could not bring themselves to entertain the idea that God could have created animals that subsequently had not worked out and had gone extinct. They believed that the spaces for life had been filled once and remained filled, and this was Jefferson's belief too. He fully expected that somewhere live mastodons would be found, along with Megalonyx.

  In this belief, Jefferson was simply remaining in tune with a basic idea about the nature of creation that was much in vogue at the time—the Great Chain of Being, which accounted in a thoroughly hierarchical manner for all creatures, with angels on top, then mankind, below which were, according to Alexander Pope's version in his Essay on Man of 1734, “Beast, bird, insect what no eye can see.” It was a fragile chain, as Pope reported: “From Nature's chain whatever link you strike, Ten or ten thousandth, breaks the chain alike.” In other words, the extinction of any type of creature would have led to the disintegration of the entire chain.

  By 1812, however, another French natural historian, Georges Cuvier, showed that extinctions had indeed occurred, and quite frequently. He could assert that by this time, for example, there were no more woolly mammoths in the Old World and no more giant ground sloths in the New. The remains of these beasts were often, if not typically, found in gravels and clays of a distinct kind, and Cuvier r
easoned that whatever had depositedthe gravel and clay had also caused the extinctions—no doubt the great floods that had occurred six thousand years earlier. He went on to point out that no one had thus far found any human remains below the deposits that bore mammoth and sloth remains, so humans had therefore probably not coexisted with those animals. Thus it could not be, as some would soon suggest, that the big mammals had been wiped out by humans. Cuvier was what came to be called a “catastrophist,” believing that catastrophic events—in this case, the Flood—from time to time brought about huge and rapid geological change. While the mammoths might have been killed off by a sudden refrigeration, all the others had perished in the Flood, their remains being found in such places as gravel beds that looked like the detritus of floods.

  With the discovery of the glaciers, the catastrophists could make the same claim—a rapid dying out—but caused in this case by the ice. As Agassiz put it with characteristic drama, “To the movement of a powerful creation succeeded the silence of death. Springs dried up, streams ceased to flow, and the sun's rays, in rising over those frozen expanses (if they still reached there), were met only by the whistling of the northern winds and the thunder of the crevasses as they split the surface of this vast ocean of ice.”

  Meanwhile the geologist Lyell, a uniformitarian of the first order, pointed out that the remains of the large and now extinct animals were, in fact, found both below and above the so-called diluvium (such as gravel beds attributed to the Flood). Thus these extinctions too had occurred in a more gradual manner.

  The questions of pace and cause soon grew more complex. At this time, for example, hippopotamuses were known to live in Africa, but now-extinct antediluvian hippos had existed in Europe. This had to suggest a gradual extinction process. But the catastrophism-uniformitarianism dichotomy continued nonetheless. Catastrophists were hard put to specify a direct cause of the extinctions they saw occurring over long periods of time—they thought they probably had something to do with changes in “station” (or what we would call habitat) caused by one or another event here and there.

  But there was another answer that some preferred. It went back as far at least as the discovery in the eighteenth century in Big Bone Lick,Kentucky, of some fossil bones that for reasons obscure were taken to be the remains of a meal of a carnivorous mastodon. One commentator of the time wrote that this huge animal must have been “at once the terror of the forest and man,” and so it made sense to think that men had killed off the mastodons to render the world safer. This indictment of humans as the potential cause of extinctions depended on two separate questions: Could men indeed wipe out a whole species? And was there any evidence suggesting that humans and the big extinct mammals had coexisted? European scientists, such as the geologist Lyell, gradually concluded that humans were capable of such activity, but few went along with the contemporaneity issue, since no satisfactory proof had emerged—no association of human remains or tools with the remains of the great beasts. But the human angle continued to have its adherents.

  One of these was the Reverend John Fleming, a Scot who, in addition to his priestly duties, was a naturalist of some note, especially a zoologist. In an early version of a technique that would plague archaeology even until the present, Fleming took two wholly unsubstantiated claims (one of them some elephantine remains found near a bronze battle-ax, the other some human bones below now-extinct mammals) and proclaimed that humans and these now-extinct beasts had lived at the same time. Therefore humans had been the guilty party. And the “extirpation operations” Fleming postulated would have taken place over a long period of time.

  Though contemporaneity—the crucial issue—remained unproven until about 1860, the “human-as-extirpator” notion became more and more popular among scientists, with even Lyell admitting that in North America it might well have been Indian arrows that had finally exterminated the American giant fauna. What was the difference between North America and Europe? American geologists were quick to take up Agassiz's glacial theories and fanned out across various parts of the continent in search of glacial traces. By the 1850s, it had already been established that the presence of glaciers in North America had not extended all the way south across the continent but had stopped, for the most part, just south of the northern tier of the United States. Again, the notion of human agency in extinctions of old was based on little more than supposition; there still was no acceptable proof. But an objective measure of such things did by this time exist: stratigraphy.

  If one could find human remains indisputably among or below those of extinct animals, it would be unarguable that people had existed prior to the divine preparation of the earth for its human inhabitants. That would be the sort of thing that would cause, among other upheavals, major seizures in the biblical view of the world and its history. It would mean that humans had not been the reason for the creation of the planet. But while Europeans did go on to find what they thought were such proofs, no one accepted their findings, and for what at the time seemed perfectly valid scientific reasons. Most discoveries of human remains associated with those of extinct animals were made in caves, and it was believed at the time that stratigraphic information in caves was not just difficult to obtain but almost impossible to get right. After all, in one case, searchers had found the bones of extinct Pleistocene creatures intimately associated with artifacts unquestionably made by the Romans. Not only were caves unreliable in themselves, but virtually all such finds were made by what the scientific sophisticates of Paris and London took not just as amateurs, but provincial ones to boot. Such people could not in fact be expected to have the theoretical or technical expertise to fulfill the criteria set down for such work. The criteria were perfectly reasonable; they called for (1) indisputable human artifacts or, better yet, human bone; (2) the remains of extinct Pleistocene animals; and (3) an undeniable relationship of the two. So no findings from caves were accepted as valid by those of a scientific bent, and for several decades more, this major theological buttress of what was taken as the core of Western civilization—the idea of a providential earth created for mankind—held firm.

  This would remain the case until the years just before and after the American Civil War. The year 1859 would be the watershed year when the short world of familiar biblical time would cease to exist. In the meantime, however, scientists were engaged in an increasingly vigorous, widespread, and sophisticated study of glacial geology that would eventually shed light not only on the ice itself and the timing of ice ages but on the mechanisms of glacial growth (and death), glaciers' geography, and the interplay among glaciers, climate, and weather. All of this growing body of information would have a profound effect on our understanding of the story of how humans populated the world, including the life and times of the first Americans.

  GLACIAL AMERICA

  Before the turn of the twentieth century, it was clear that the North American ice had advanced southward and then receded several times over some long period of time and that the last advance had brought the glacial edge as far south as northern New Jersey, Cincinnati, and Saint Louis (see map). Ice had stretched along a wildly erratic line from the Atlantic westwardalmost to the Rocky Mountains, north across Canada, and eastward to cover Greenland and even Iceland.

  North America and adjacent Siberia during the glacial maximum, ca. 20,000 B.P. (after Porter, 1988).

  Today we know that for at least the last 1.89 million years, the world has been subject to the repeated advances of ice (periods called “glacials”) and retreats (called “interglacials”) during what is called the Pleistocene Epoch, a term Charles Lyell coined from the Greek words for “most” and “recent.” The Pleistocene is said to have ended ten thousand years ago with the last glacial retreat (though that date's main claim is that it is a nice round number), and we currently live in the Holocene—a word later coined by a French scholar that also etymologically means “most recent,” but never mind. Another way to look at it is to put aside the self-satisfied notio
n that we thoroughly modern humans are so marvelous that we must have our very own epoch, the Holocene, and admit that we simply live in the latest Pleistocene interglacial. The beginning of the Holocene is in fact pegged to the beginning of the latest interglacial, and it can be expected to be succeeded by another glacial period—whatever the near-term effects of the current state of global warming. Anatomically modern human beings came into being only within the last 120,000 years, which is to say, only in the last fifteenth of the Pleistocene. Clovis culture, so long thought to be the first in the Americas, existed for only a nanoblink of geological time (about a half millennium) at the Pleistocene's very end, when the great ice sheets that covered about a quarter of the planet's landmass had begun to recede.

  This vast ice sheet, which at its height covered most of Canada and a good deal of the northern part of the United States, is called the Laurentide Glacier. Part of Alaska and the Yukon Territory, as well as the so-called bridge known as Beringia, had been spared, but ice had crept south from the rest of Alaska, turning the Aleutian Islands into an icebound thumb and covering the west coast of North America down to Seattle and east over the Rocky Mountains. This long, thin glacier is called the Cordilleran Glacier, and for much, if not most, of its career it was separated from the Laurentide.

  Though the two great glaciers are often shown as conjoined during the height of the last glacial maximum, there is very contradictory evidence on precisely when and for how long such a confluence may have occurred. Exactly when the corridor was open or closed has been debated endlessly,especially by Clovis Firsters. According to their argument, any migrants into the New World were bottled up in the unglaciated Bering Refugium until the ice sheets parted like the Red Sea for some Clovis Moses to lead his intrepid band of spear-toting, mammoth-slaying wayfarers to the south. Which is very dramatic and probably very wrong. The bottom line on the corridor is that for most of the time between 75,000 and 10,000 years ago it was open. While it may not have been particularly welcoming—cold and windy, with icy lakes and tundralike conditions—animals could and did live there, and people obviously moved through it sometime after passing over the land bridge.