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Article

Alexander F. Blackwood and Jayne Wilkins

The Middle Stone Age (MSA) is a period of African prehistory characterized by the production of flake-based assemblages, often with a focus on stone points and blades using prepared core reduction techniques. The MSA follows the Earlier Stone Age and precedes the Later Stone Age, although the boundaries between these periods are not as sharp as originally defined. The MSA is generally regarded as having started by at least three hundred thousand years ago (ka) and lasted until roughly forty to twenty thousand years ago. Identifying the chronological limits for the MSA is challenging because some aspects of MSA technology are found in assemblages outside this time range that also have Earlier or Later Stone Age-type tools. The earlier part of the MSA is associated with fossils belonging to the Homo sapiens clade (alternatively referred to as Homo heidelbergensis, Homo rhodesiensis, or archaic Homo sapiens). The later part of the MSA post 200 ka is associated with Homo sapiens. Determining the processes underlying the anatomical evolution of Homo sapiens during the MSA is a major aim of ongoing research, however fossil remains are rare. Across the African continent and through time, the MSA exhibits a high degree of variability in the types of stone tools that were manufactured and used. Archaeologists have used this variability to define several technocomplexes and industries within the MSA that include, but are not limited to, the “Aterian,” “Howiesons Poort,” “Still Bay,” and “Lupemban.” Variation in point styles, presumably hafted to wooden handles or in some cases projectiles, is considered a hallmark of the regional diversification that originates in the MSA. This variability, which is temporally and spatially restricted, differs in both degree and kind from the preceding Earlier Stone Age. The MSA is significant from an evolutionary perspective because, in addition to being associated with the anatomical origins of Homo sapiens, this period in time documents several significant changes in human behavior. Populations in the MSA practiced a foraging economy, were proficient hunters, and began efficiently and systematically utilizing aquatic resources such as shellfish and freshwater fish for the first time. Other significant changes include the elaboration of and increased reliance on symbolic resources and complex technologies. For example, the first known externally stored symbols in the form of crosshatched incised pigments date to ~100 ka. In contexts of similar age, shell beads for making jewelry have been recovered from Morocco and South Africa. The earliest evidence for complex projectiles dates to at least 74 ka. The meaning, utility, and persistence of symbols and complex technologies depend on social conventions and confer advantages in contexts that involve long-distance, complex social networks. While many of these earliest finds linked to behavioral modernity have so far been geographically restricted, the combined suite of genetic, fossil, and archaeological evidence may better support a polycentric African origin for Homo sapiens over the course of the MSA.

Article

Yonatan Sahle

The Stone Age record is longer and better documented in eastern Africa. Archaeological and fossil evidence derives particularly from sites within the Rift Valley of the region, often with secure radiometric age estimates. Despite a relatively late start and disproportionate focus on earlier periods and open-air sites within the rift, scientific research into the region’s Stone Age record continues to play a central role in our understanding of human evolution. Putative stone tools and cutmarked bones from two Late Pliocene (3.6–2.58 million years ago or Ma) contexts are exclusive to eastern Africa, as is conclusive evidence for these by 2.5 Ma. The earliest indisputable technological traces appear in the form of simple flakes and core tools as well as surface-modified bones. It is not clear what triggered this invention, or whether there was a more rudimentary precursor to it. Neither is it certain which hominin lineage started this technology, or if it hunted or only scavenged carcasses. Well-provenienced archaeological occurrences predating 2.0 Ma are limited to sites in Ethiopia and Kenya, becoming more common across eastern Africa and beyond only later. By 1.75 Ma, lithic technologies that included heavy-duty and large cutting tools appeared in Ethiopian and Kenyan localities. Several details about this technological tradition are still inadequately understood, although its appearance in eastern Africa roughly coincides with that of Homo erectus/ergaster. By far the longest-lived Stone Age tradition, hominins with such technologies successfully inhabited high-altitude environments as early as 1.5 Ma, and expanded within and beyond Africaeven earlier. Hunting and use of fire probably started in the earlier part of this technological tradition. Small-sized and highly diverse tool forms gradually and variably started to replace heavy-duty and large cutting tools beginning c. 300 thousand years ago (ka). Conventional wisdom associates this technological and behavioral shift with the rise of Homo sapiens, although the oldest undisputed representatives of our species continued to use large cutting tools in eastern Africa after 200 ka. In addition to small retouched tools, often on products from prepared cores, significant innovations such as hafting and ranged weaponry emerged during the length of this technological tradition. Increasingly complex sociocultural behaviors, including mortuary practices, mark the later part of this period in eastern Africa. The consolidation of such skills and behaviors, besides ecological/demographic dynamics, may have enabled the ultimately decisive Out-of-Africa dispersal of our species, from eastern Africa, 50–80 ka. Even smaller and more diverse stone tool forms and other sociocultural innovations evolved in many areas of eastern Africa by 50 ka. Miniaturization and diversification allowed for the adoption of more complex technologies, including intentional blunting and microlithization. Some of these were used as parts of sophisticated composite implements, such as the bow and arrow. Complex behaviors involving personal ornamentation, symbolism, and rituals that resembled the lifeways of ethnographically known hunter-gatherer populations were similarly adopted. These dynamics eventually led to the development of new technological and socioeconomic systems marked by the inception of agriculture and attendant lifeways.

Article

Michael Chazan

Levallois refers to a way of making stone tools that is a significant component of the technological adaptations of both Neanderthals and early modern humans. Although distinctive Levallois artifacts were identified already in the 19th century, a consensus on the definition of the Levallois and clear criteria for distinguishing Levallois from non-Levallois artifacts remain elusive. At a general level, Levallois is one variant on prepared core technology. In a prepared core approach to stone tool manufacture, the worked material (the core) is configured and maintained to allow for the production of detached pieces (flakes) whose morphology is constrained by the production process. The difficulty for archaeologists is that Levallois refers to a particular process of manufacture rather than a discrete finality. The study of Levallois exposes limitations of typological approaches to artifact analysis and forces a consideration of the challenges in creating a solid empirical basis for characterizing technological processes.

Article

The Southern African Stone Age covers the longest period in human history, that is, the last three million years of human evolution and adaptation in a region south of the 18th parallel south. The region includes the countries of Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland, and Zimbabwe, with a northern border marked by the Kunene River between Angola and Namibia, the Cuando River on the borders of Angola, Namibia, and Botswana, and the Zambezi River. It is divided into three main phases, known as Early, Middle, and Later Stone Age. The Early Stone Age had its beginning about three million years ago with the development of Australopithecus, found in South Africa in the region called the Cradle of Humankind. The earliest stone tools in the region were discovered in the cave of Sterkfontein and are dated to around two million years ago. These first stone tools, which include choppers, polyhedrons, and subspheroids, among other artifacts, are part of an industrial complex known as the Oldowan, which lasted for a few hundred thousand of years. It was followed by the Acheulean, known by its unique large cutting tools, the handaxes, cleavers, and picks, starting about 1.8 million years ago. During this period, species such as Homo habilis and Homo erectus/ergaster walked over southern Africa. The Middle Stone Age, starting about three hundred thousand years ago, seems to be directly associated with the emergence of a new species, Homo sapiens. This phase shows a wide cultural diversity in the region, and in fact across the whole African continent, both in time and space. This is a phase drastically marked by technological and cultural innovations, such as the use of bow and arrow, hafting, bone tools, lithic heat treatment, use of pigments, production of body ornaments such as beads, art in the form of engravings, and, finally, the systematic inclusion of shellfish and plants in the human diet. These innovations, however, were not used all in the same location. This congregation of techniques and innovations took place only during the next phase, the Later Stone Age, which started around thirty-five thousand years ago. It is likely the result of an important demographic change that occurred as a response to climatic oscillations that took place at the world level. Like the Middle Stone Age, the Later Stone Age saw an incredible range of cultural diversity in the large region of southern Africa. Traditionally, it was believed that the main differences between the Middle and Later Stone Ages were based on a dichotomy where, on one side, points and flake industries resulting from prepared cores such as Levallois were present, and on the other, simple cores producing microlithic assemblages, sometimes geometric, together with art, and beads and organic tools were present. Today, however, that simplistic contrast is known to be wrong, and the differences in cultural complexity are more a matter of concentration than innovation. The Later Stone Age hunter-gatherers were finally slowly replaced by farmers and herders and later by Iron Age populations, between twenty-five hundred years ago and the recent historical present.