Fiedel Prehistory of the Americas Cap2 From Africa to Siberia

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<ul><li><p>2 From Africa to Siberia: early human migrations in the Old WorldThe journey of the ancestral Paleo-Indians across the land bridge between Siberia and Alaska, more than 12,000 years ago, was the final stage of a process of migration and colonization that had begun 1.5 million years earlier. Continual northward and eastward movements of hunter-gatherer bands had resulted in the extension of the range of human habitation from the tropical savannas of southern and eastern Africa to the cold, dry tundra- steppes of northern Asia. In adapting to the diverse environments of this vast region, humans had changed both physically and culturally. In this chapter we will briefly review the major evolutionary developments that occurred prior to the arrival of early humans at the threshold of the New World. Some familiarity with the prehistory of Eurasia is necessary, both to see the Paleo-Indian migration in a broader perspective, and in order intelligently to evaluate arguments concerning the date and nature of the initial colonization of the Americas.</p><p>EARLY HOMINIDS OF AFRICAOn the basis of recent fossil discoveries and comparative studies of proteins and DNA, a consensus has been reached among most anthropologists that the ancestral human line diverged from that of the chimpanzee in Africa, some time between 10 and 5 million years ago. The earliest hominid species that is well-represented by fossil remains is Australopithecus afarensis, which dates from about 3.5 million years ago. Fossils found in Ethiopia and Tanzania show that A. afarensis walked bipedally, like later humans. However, their brains were still ape-sized, and there is no evidence that they hunted or used tools. Between 3 and 2 million years ago, probable descendants of A. afarensis lived in eastern and southern Africa. At least two, and probably three species of Australopithecines are represented by fossils of this period: a smaller, gracile type, A. africanus, and two larger types, A. robustus in southern Africa and A. boisei in eastern Africa. The larger varieties are thought to have ultimately become extinct; but whetherA. africanus suffered the same fate, or was ancestral to later humans, is not yet clear. In any case, a larger-brained hominid, Homo habilis, appeared</p><p>22</p></li><li><p>1 Olduvai Gorge2 LakeTurkana3 Java (Trinil and Solo)4 Hsihoutu5 Lantien6 Choukoutien7 L'Escale8 Terra Amata9 Chesowanja</p><p>10 Karatau11 Mapa12 Tingtsun13 Shui-tung-kou14 Khotylevo15 Lebenstedt16 Molodova17 Border Cave18 Niah Cave19 Lake Mungo20 Kow Swamp21 Vogelherd22 Sungir23 Dolni Vstonice24 Amvrocievkaya25 Mal'ta26 Aldan sites</p><p>Fig. 4. Old World Paleolithic sites. Glaciated areas are indicated by stippling. Note the extended coastlines resulting from lower sea level.</p><p>t</p></li><li><p>Prehistory of the Americasin Africa about 2 million years ago. The growth of the brain, from the 450cc of A. africanus to the 600-800cc of Homo habilis, seems to have been causally related to the first use of stone tools and to the eating of hunted or scavenged meat. At 2 million-year-old sites in Olduvai Gorge and near Lake Turkana, close to the find-spots of Homo habilis specimens, broken bones of elephants, hippopotamus, antelopes, and other animals have been found, in association with stone tools. These Oldowan, or pebble tools, include both simple choppers (or cores) and sharp flakes, which were probably used as knives and scrapers. The hominids, with their small canines and clawless fingers, needed such tools to slice through the tough hides of animal carcasses. The habit of meat eating seems to have distinguished the early members of the genus Homo from their Australo- pithecine cousins, whose huge molars imply an almost exclusively vegetarian diet of fibrous fruits, roots, and seeds.A lower jaw found on the island of Java, in deposits that may be as old as 1.8 million years, resembles Homo habilis specimens from Olduvai Gorge. Recently, Chinese archaeologists have reported their discovery of Oldowan- like cores and flakes, along with animal bones, at the Hsihoutu site in Shangsi province; this site may also be about 1.8 million years old (Gowlett 1984). If further research confirms the early dating of these finds, we will have evidence that bands of Homo habilis had migrated into Asia, reaching its easternmost regions almost 2 million years ago. However, most anthropologists currently believe that hominids did not enter Asia before 1 million to 700,000 years ago.Back in eastern Africa, there is evidence of the appearance of a more advanced hominid about 1.5 million years ago. This hominid, Homo erectus, is generally assumed to have evolved from Homo habilis. A more highly developed stone tool industry, the Acheulian, seems to have been introduced by Homo erectus. Acheulian tools appeared at sites in eastern and southern Africa about 1.5 million years ago, and the industry later spread to Europe and western Asia. The most typical Acheulian artifact was the handaxe. These large, teardrop-shaped, bifacially chipped tools may have served a variety of functions, but a recent study of edge wear on some English specimens has shown that they were used to skin and butcher animals. This is not surprising, because archaeologists have excavated a number of sites where Homo erectus killed and butchered animals, such as giant baboons at Olorgesailie (Kenya), elephants at Torralba and Ambrona (Spain), and cattlelike Pelorovis at Olduvai.</p><p>HOMO ERECTUS IN EASTERN ASIASkeletal remains of Homo erectus have been found at several sites in eastern Asia. Fossils recovered from the Trinil beds of Java are probably 700,000</p><p>24</p></li><li><p>From Africa to Siberiato 800,000 years old, and a skull from Lantien, China, is of comparable age. Another famous Chinese site, where remains of 40 individuals were discovered, is Choukoutien, southwest of Peking. Unfortunately, the original specimens, excavated in the 1930s, were lost in the chaos caused by the Japanese invasion of China, but well-made casts survived, permitting further scientific analysis of the finds. Studies of the skulls and casts revealed several intriguing similarities between the Choukoutien erectus skulls and those of modern Mongoloids and Native Americans. These features include the mid-line ridge or keel along the top of the skull; the mandibular torus, an overgrowth of the lower jaw that is particularly common among Eskimos; molars with large pulp cavities (taurodont), and shovel-shaped incisors (upper front teeth with concave inner surfaces) (Laughlin 1966). Although many of the dozen Mongoloid-like traits discerned in the Choukoutien fossils occur in some individuals in modern populations in other parts of the world, these traits nevertheless strongly suggest that Chinese Homo erectus contributed some genes to later Asian and Native American Homo sapiens.Besides fossil hominids, the Choukoutien caves also yielded evidence of early human lifeways about 400,000 to 350,000 years ago. The inhabitants of Choukoutien were efficient hunters, preying upon giant sheep, horses, pigs, buffalo, rhinoceros, and - most often - deer. Excavators of the cave sites found many charred bones of these animals, showing that Homo erectus used fire not only for warmth but also for cooking. Deep charcoal deposits marked the locations of the ancient hearths, which had apparently been kept burning continuously.Controlled use of fire was essential if hominids were to succeed in occupying regions with temperate (or colder) climates; without its artificial warmth, furless, tropics-adapted humans could not have survived the winter months. There is a good possibility that Homo erectus may already have known how to use fire when he arrived in northern areas. At the 1.5 million- year-old campsite of Chesowanja, in Kenya, burnt clay and stones seem to be the remnants of ancient hearths. Fire may have been used more than 1 million years ago at a few other sites in eastern Africa (Gowlett 1984). Later, indubitable traces of fire have been found at two French sites, LEscale, dated to about 700,000 years ago, and the 400,000-year-old campsite at Terra Amata, on the Riviera. We cannot tell whether Homo erectus knew how to start fires, or only preserved naturally occurring flames; the earliest known fire-starting tools come from Upper Paleolithic sites.The faunal remains from Choukoutien indicate that Homo erectus lived there during an interglacial episode in the Middle Pleistocene. The Pleistocene, or Ice Age, began about 1.7 million years ago (actually, there were previous glacial advances as early as 2.5 million years ago, but</p><p>25</p></li><li><p>Prehistory of the Americasthe Pliocene-Pleistocene boundary has been arbitrarily defined on the basis of marked changes in marine sediments). It used to be thought that there had been only four periods of glaciation during the Pleistocene, but geologists now realize that there have been 17 glacial-interglacial cycles, with maximum southward extension of ice sheets occurring every 100,000 years. The intervening warm periods (interglacials) have been quite brief, usually lasting only 10,000 years.Despite the fact that Choukoutien was inhabited during an interglacial, the winters must have posed some difficulty for Homo erectus; the site lies close to the apparent northern limit of human occupation of Middle Pleistocene (700,000-130,000 B.P.) Eurasia. There are probable sites of this age a little farther east, at about the same latitude (40N), in Korea and Japan (which was occasionally connected to the Asian mainland). A Middle Pleistocene site is also reported to have been found northwest of Choukoutien, in Mongolia. At the opposite end of Eurasia, Homo erectus populations seem to have ventured north into Germany and even into the British Isles (above 50N) during interglacials, only to retreat southward as the ice advanced again. There is evidence at the site of Karatau of similar north-south fluctuations of populations in central Asia, about 250,000 years ago. The apparent absence of Middle Pleistocene sites, except in western Europe, north of about 45N latitude, suggests that Homo erectus lacked the cultural equipment necessary to survive in the snow climates that prevail farther north, where, even today, winter temperatures often fall below freezing.The thousands of stone tools made by Homo erectus at Choukoutien were simple choppers and sharp-edged flakes of quartz, which resembled the much earlier Oldowan tools of eastern Africa. Handaxes have been recovered from a few Middle Pleistocene sites in Mongolia and Korea, but they are absent from the great majority of Far Eastern assemblages of this period. These contain instead simple chopper-chopping tools, similar to those found at Choukoutien. The near total absence of hand axes in eastern Asia, when they were so common in contemporary Europe, Africa, and western Asia, has yet to be satisfactorily explained.It should be clear from the foregoing discussion that the handaxelike artifacts occasionally found in surface collections in the Americas are most unlikely to have been made by Homo erectus. Any hypothetical Middle Pleistocene immigrants would probably have used only chopper-chopping tools. However, in view of the absence of early sites in far northern Eurasia, the possibility that Asian Homo erectus bands could have survived long treks through Siberia, even during an interglacial, is very remote.</p><p>26</p></li><li><p>From Africa to SiberiaTHE ORIGIN AND EXPANSION OFHOMO SAPIENS</p><p>By about 300,000 to 200,000 years ago, some Homo erectus populations had evolved into a larger-brained, higher-browed, smaller-faced species, Homo sapiens. After the last interglacial, about 130,000-120,000 B.P., Europe was occupied by a distinctive subspecies of archaic sapiens, Homo sapiens neanderthalensis. Neanderthals were stockier and more heavily muscled than modern humans, with long faces, heavy brow ridges, and chinless jaws. They were nevertheless intelligent, resourceful people who adapted successfully to the deteriorating climate and environments of the last glaciation (known as Wiirm or Weichsel in Europe, Wisconsin in America).Outside Europe and North Africa, contemporary populations of archaic sapiens represent a comparable evolutionary stage. In eastern Asia, Neanderthal-like fossils have been found at Mapa and Tingtsun in China, and at Solo in Java. These Asian specimens have brains in the size range of modern sapiens, yet also display primitive features that demonstrate their descent from earlier erectus populations.In Europe, North Africa, and western Asia, Neanderthals made and used some 60 types of stone tools - scrapers, cutting tools, and points - which are referred to collectively as the Mousterian industry (after the site of Le Moustier in France). Acheulian handaxes had tended to become smaller and to be replaced by retouched flake knives and scrapers as early as 200.000 to 150,000 years ago, and this trend continued in the Mousterian assemblages, which were produced from about 100,000-40,000 B.P. Some Mousterian toolmakers continued to turn out Acheulian-style handaxes, but most Mousterian tools were flakes, carefully detached from prepared cores and then retouched into the desired forms. A common core preparation technique, which produced large flakes and remnant cores shaped like tortoise shells, is called Levallois. Middle Paleolithic assemblages that contain numerous tools made in this way are called Levallois-Mousterian.Among the Mousterian flake tools were the first haftable spearheads; before this, Acheulian hunters had used wooden spears, with whittled and fire-hardened tips. Late Mousterian assemblages in central and eastern Europe, dated at about 40,000-35,000 B.P., include particularly well- chipped spearpoints. Some archaeologists have speculated that these bifacially thinned, leaf-shaped points might represent the ultimate source of the point-making tradition that was carried into the Americas by the first immigrants (Mller-Beck 1967).Flake tools resembling the Mousterian artifacts of the West have been found at several sites in China and Inner Mongolia. At the Mongolian site of Shui-tung-kou, Levallois-Mousterian scrapers and saw-toothed flakes27</p></li><li><p>Prehistory of the Americas(denticulates) were present, along with blade tools of Upper Paleolithic type. The presence of blades suggests that this might be a late Mousterian site, perhaps 30,000 years old, although an earlier date, closer to 70,000 B.P., has also been proposed. Makers of Mousterian tools probably entered Mongolia from Central Asia. They do not seem to have stayed in the region very long, perhaps because the climate worsened. Following their departure, Mongolia was occupied by makers of chopper-chopping tools, who probably came from China. As we shall soon see, Levallois-Mousterian tools are reported to have been found at several sites in Siberia, which may have been colonized briefly during a relatively warm interstadial episode, around 45,000-35,000 B.P.It was somewhat cooler and wetter...</p></li></ul>