Across Atlantic Ice
Page 3
The late Paleolithic technologies found in Asia are predominately microblades made from prepared wedge-shaped cores (for more information, see chapter 1). In this technology, segments of microblades are inset into grooves in long, narrow, pointed rods of bone, antler, or ivory to form weapon tips and knives (figure Intro.3). This is in sharp contrast to Clovis technology, whose weapon tips are thin, flat bifaces—stones flaked to have one continuous edge and two faces—with concave bases. The few cases of biface technology in Asia are thicker relative to their width and usually pointed at both ends or stemmed (bilaterally indented above the base). Put simply, the Paleolithic northern Asians had a totally different concept of weaponry than Clovis peoples—making them seem unlikely Clovis ancestors.
The refinement of radiocarbon studies of the late Paleolithic sites in far northeastern Asia produced another surprise: all dated sites were either the same age as or younger than Clovis sites. One must travel 1,500 miles or more away from the Bering Strait into Asia to find radiocarbon-dated sites that are much older than approximately 13,000 years old. Again, there seemed to be no evidence of Clovis ancestors in Asia.
To further complicate the deceptively simple Siberia-to-Clovis model, recent research has seriously challenged the presence of an ice-free corridor ecologically capable of supporting human life in time to account for ancestral Clovis migrants.14 If a model allows the first New World immigrants only their feet for transportation, they could have come through the corridor only after that environment was able to sustain plant and animal life, yet people were well established in southern latitudes before the corridor was biologically viable. For the Siberian model to work, Clovis ancestors must have trekked southward from eastern Beringia during a previous warm interglacial period, or at least 28,000 years ago. If that was the case, these Paleolithic people lived in the Americas for nearly 17,000 years without leaving a credible record of their existence here, or in northeastern Asia for that matter. The lack of evidence to support an early entry hypothesis compels us to reject the idea of a much earlier trek.
We are left with a major conundrum. Since there are no archaeological sites in far northeastern Siberia that are older than Clovis, there is no ancestral base there from which Clovis could have developed. The only artifacts found in Beringia that appear to be related to Clovis are clearly younger, so if they are indeed related they were made by Clovis descendants, not Clovis ancestors. Because Clovis technology appears in North America before the Canadian ice-free corridor could support human life, it would have to date to an earlier interglacial period. But there is no clear evidence of such an early occupation of the Americas. A logical conclusion is that Clovis ancestors must have bypassed the great continental glaciers on their way to the New World. Could they have accomplished this by ocean voyages, either skirting along coastlines and marine glaciers or crossing by boat? Were the Clovis mammoth hunters descendants of mariners?
INTRO.3.
Replica of a Siberian compound knife from the Kokorevo Site, with Dyuktai microblade core and microblade: (a) obverse side of microblade core and blade; (b) reverse side of microblade core and microblade; (c) microblade broken into sections, with arrows showing where the uncurved middle section is inset into the slotted bone knife; (d) edge view of knife; (e) side view of knife.
More than thirty years ago Knut Fladmark hypothesized that maritime peoples exploring along the north Pacific Rim had colonized the Americas.15 But the idea proved difficult to support, for lack of artifactual evidence. Boats, unlike stone points, are fragile and unlikely to survive thousands of years; even if they did, most places one is likely to find them are now hundreds of feet below sea level. Most archaeologists of Fladmark’s time summarily dismissed the thought that Paleolithic peoples might have used oceangoing watercraft. Only recently have scholars taken his idea seriously, in part because of the apparent impossibility of entry into the Americas through the ice-free corridor and in part because of increasing inferential evidence of oceangoing Paleolithic peoples in the southwestern Pacific.16
A CONVERGENCE OF POSSIBILITIES
Even though mainstream scholars have accepted the logic of Clovis people being the first inhabitants of the New World, others have long held that the peopling of the Americas was a more complicated issue, pointing to many discoveries of seemingly more ancient human occupations.17
During the summer of 1996, Dennis and the Clovis scholar Vance Haynes were touring the eastern United States, visiting various Clovis localities and collections. High on their list was Cactus Hill, southeast of Richmond, Virginia. This stratified site, excavated by Joe and Lynn McAvoy, was the latest contender as a pre-Clovis occupation. The site boasts a sequence of cultures, including late Paleoindian, Clovis, and for the first time undisputed cultural artifacts in an occupation level below Clovis. These artifacts were highly reminiscent of Clovis, with relatively large blades, tools produced from blades and flakes, polyhedral flake cores, and two projectile points (figure Intro.4b). In general, the tools would fit easily into a Clovis assemblage, except for the two weapon tips. These points, although similar to Clovis points in form, were much thinner and had bases that were thinned instead of fluted. Haynes suggested that there were multiple Clovis occupations and that the weapon tips were simply early Clovis points that were broken during use and given a new base, accounting for their thinness and lack of flutes. A radiocarbon date from a probable hearth feature indicated this “early Clovis” assemblage was nearly 16,000 radiocarbon years old.
Soon after his visit to Cactus Hill, Dennis and the Paleoindian expert Pegi Jodry participated in an exhibit in Solutré, France, the site where the European Upper Paleolithic Solutrean culture was first identified and after which it was named. The Solutrean has been dated between circa 18,000 and 25,000 years old. The goal of the exhibit was to compare and showcase Solutrean and Clovis caches—collections of items ranging from special ceremonial offerings to stored equipment or food supplies. Dennis and Pegi became acquainted with the range of French Solutrean artifacts and Solutrean lithic technology and also visited an exhibit on the Solutrean of the Iberian Peninsula that included artifacts from northern Spain. They were impressed by the high degree of flaked-stone and bone technology shared between Solutrean and Clovis artifacts, and Dennis was especially struck by the astonishing similarity of the Spanish Solutrean indented-base projectile points (figure Intro.4a) to those he had seen just weeks earlier at Cactus Hill. Could the ancestors of Clovis have been the Solutrean people of Europe rather than the long-sought Asians?
Several scholars in the past had pointed out the similarities between Clovis and Solutrean technology, but seemingly significant obstacles prevented little more discussion than simply musing over their similarities.18 Chief among the obstacles were the time gap of 5,000 years between the two cultures and the belief that Paleolithic people did not have boats and could not, therefore, have navigated the stormy ice age Atlantic Ocean. In the face of these problems, most researchers simply dismissed the technological similarities as examples of independent invention of equipment used by unrelated people to exploit similar environments.
INTRO.4.
Indented base points: (a) Spanish Solutrean; (b) Cactus Hill. Outlines show sections.
The Solutrean people carved out a living in southwest Europe during the Last Glacial Maximum (LGM), when most of northwest Europe not covered by glaciers was likely a barren, cold, wind-swept region. It is no coincidence that the majority of Solutrean sites are found near coastal settings or in river valleys, which offered better resources and more amenable environments. It appears that these people lived in the coastal ecological zones for some 5,500 years, and it only makes sense that these fully modern humans learned to exploit the available resources and developed many technological innovations to improve their efficiency at doing so. Could they have had seagoing technologies? Could they have been the ancestors of the people who lived at Cactus Hill?
During Solutrean times the polar front arched abo
ut 1,600 miles across the North Atlantic, creating an ice bridge that connected the last ice age coastline of southwest Europe to an island chain off the coast of Canada now known as the Grand Banks. The front would have brought with it all the life-forms that evolved and adapted to living along the ice edge. Solutrean people would have witnessed the many moods of their ice edge environment, growing and blooming, waxing and waning in natural harmony with the weather shifts that punctuated the ice age Paleolithic world. Of course, being out on the ice, they would have learned to harvest the fruits of what the Inuit elders call the “garden” at their doorstep. And while hunting in this icy wonderland, they would have gained an ever-expanding familiarity with and knowledge of this environment that could have carried them to the Americas. Certainly Solutrean technology is similar to both Clovis and Cactus Hill technologies, and if sites like Cactus Hill represent a version of Clovis several centuries older but still in the Americas, the Solutrean connection seems a much more plausible explanation for Clovis origins than the currently accepted northeast Asian origin theory.
Dennis contacted Bruce to discuss ideas about the possible Iberian connection. Bruce had written his doctoral dissertation on Paleolithic technology and worked at length with the French archaeologist François Bordes, the father of modern European flintknapping—making artifacts from flint stones by applying controlled percussion or pressure to shape the stone into a useful tool. Bruce’s skill in flaking chipped stone artifacts and his mastery of most flaking techniques were known around the world, and he had conducted extensive analyses on stone artifact collections from Eurasia, including several Siberian sites.
Bruce had already been impressed with the similarity of Solutrean and Clovis technologies. While working in France in 1970, he had observed that when Solutrean flintknappers made bifaces, they executed flakes that passed from one edge of the artifact and across its face and ended at the opposite edge or sometimes even wrapped around the edge (figure Intro.5). Bordes called this outrepassé, or overshot, flaking. Most flintknappers, including Bordes, considered these flakes mistakes made during flintknapping, because such a flake produced by an inexpert knapper usually results in a manufacturing failure. Indeed, some Solutrean bifaces were discarded during manufacture because of an outrepassé flake gone bad. The deliberate use of this difficult technique seemed rather unlikely, but the possibility was fascinating.
Years later, when Bruce was working with the archaeologist George Frison at the Agate Basin Site in Wyoming, they tested a locality, known as Sheaman, where flakes were observed eroding from a dry stream bank.19 At first they found only flakes, many quite large, produced during biface manufacture. These flakes varied in size and form, but many were very flat and had more or less parallel sides, and many exhibited the distinctive terminations of outrerpassé flakes. Compared to the flakes Bruce and Frison had found elsewhere, their platforms (intentionally prepared surfaces where the blow was delivered to remove a flake) were unusually wide, straight, and heavily abraded. Bruce was struck by the distinctiveness of the flakes and recalled that even down to the details of how the platforms were prepared, they appeared to represent the same outrepassé technique he remembered seeing in the French Solutrean.
The next season’s excavations revealed Sheaman to be a Clovis occupation. Bruce recognized that the flakes were probably diagnostic of Clovis and began to note their presence in other assemblages. He has now recorded them in sites across North America, and without exception, when they are present in significant numbers, they have been found to be Clovis. Because the technique is unique to Clovis and Solutrean biface manufacture, even down to the details of how the platforms were prepared, the idea of a historic connection between the two groups makes sense, especially since the many collections the authors have examined from Siberia show no indication that the overshot technique was systematically used there. And now there seemed to be additional technological characteristics shared by the Cactus Hill and the Spanish Solutrean projectile points, and the Cactus Hill radiocarbon dates were suggesting an overlap with Solutrean times. But was there enough evidence to overcome well-entrenched assumptions and postulate a historical relationship between the Paleolithic Europeans and Clovis people in North America?
INTRO.5.
Clovis overshot flaking: (a) early stage of manufacture; (b) middle stage of manufacture; (c) finished projectile point. Shading indicates overshot flake scars.
Several decades earlier E. F. Greenman had published a major paper hypothesizing that European Paleolithic peoples traveling by boat had lived on and explored the LGM “archipelago” of large ice floes in the North Atlantic until they discovered North America.20 Most archaeologists of the time rejected Greenman’s hypothesis because of his inconclusive and indiscriminate comparisons of North American and European technologies of multiple time periods over vast geographic areas, and no one since that time had taken the issue seriously enough to conduct in-depth comparisons of the Paleolithic technologies of Europe and North America. Moreover, presumptions about genetic relationships based on physical similarities of modern Native Americans and northeast Asians were still strong, and evidence of Paleolithic travelers across the Atlantic still weak.
But the discovery in the Columbia River Basin of the so-called Kennewick Man—with seemingly European features but dated to 9,500 years before the present (BP)—suggested that human physical traits were not nearly as simple and conclusive as had been assumed.21 More recently, genetic studies of living peoples around the world have mapped the history of human relationships, and among the results are indications of a distinct human genetic trait shared by some prehistoric and modern Native Americans and some Paleolithic and modern Europeans.22 At the same time, new tools and methodology have allowed the exploration of submerged maritime Paleolithic sites and the collection of data that is relevant to any hypothesis about early coastal migrations.23 (Sea-voyaging cultures probably existed worldwide as much as 30,000 years ago, and perhaps as much as 130,000 years ago in the Mediterranean.)24 Taken together, these new lines of evidence build a picture that makes at least as much sense as the traditional one of Siberians walking to New Mexico before 12,000 B.P. In this newer picture the first people to settle in the New World—or if not the first, then the earliest we have evidence of—exploited the North Atlantic from western Europe. This is the basis of the Solutrean hypothesis.
THE SOLUTREAN HYPOTHESIS
Who were the first Americans? The Solutrean hypothesis, in simple outline form, is that during the Last Glacial Maximum, sometime between 25,000 and 13,000 years ago, members of the Solutrean culture in the southwest coastal regions of Europe were led by subsistence behavior appropriate to their time and place to exploit the ice-edge environment of the polar front across the North Atlantic and colonize North America to become—after several millennia—what we know as the Clovis peoples, who eventually spread far and wide across the Americas. This does not necessarily mean that the Clovis people were the ancestors—or the only ancestors—of contemporary Native Americans, and it does not mean that Paleolithic northeast Asians did not also colonize the Americas. It does mean, in concert with other strands of evidence, that Clovis is part of the rich, complex, and wonderful story of the ebb and flow of people whose descendants are what we call Native Americans.
The past decade, in which we have been researching this theory, has produced increasing amounts of new information, and the pace is quickening. Barely a month goes by when there isn’t some new archaeological discovery, new dating of old sites, new evidence of the LGM environment, new DNA interpretation, or other new finding that has the potential to significantly add to and alter our understanding of how people colonized the Americas. For the most part this new evidence has lent support to the theories that Clovis wasn’t the first culture in the Americas and that people likely came to the Americas from different places at different times and in different manners. Indeed, it has been difficult to bring a conclusion to this book with all of the new and exciti
ng discoveries.
Humans seek new places to live for at least two reasons: it is hard to make a living where they come from, and somewhere else seems more attractive. This is known as the push-pull concept. Stress encourages people to look for new homes, and perceived plenty is attractive. The hypothesis that we will present is that a combination of limited territory and a seasonally impoverished terrestrial environment adjacent to a seasonally rich marine environment attracted Solutrean people to incorporate a maritime component into their subsistence patterns. As these people learned to exploit the sea, they followed the southern ice margin of the North Atlantic, eventually making landfall in North America, where at least some remained. During Solutrean times there may have been many accidental and purposeful trips back and forth between southwest Europe and North America. As the ice age waned, the sea ice edge and its associated resources retreated northward, the glaciers melted, and the sea level rose, flooding the continental shelf and increasing the distances across open water. At the same time, the environment of the European mainland improved and the need for a maritime focus lessened. It was no longer necessary, or attractive, to ply the North Atlantic. But by then humans had established a foothold in eastern North America—the earliest foothold on record.