Early Paleolithic industry characterized by handaxes and similar types of modified stone tools. Acheulean artifact assemblages are known from ca. 1.5 to 0.2Ma and span Africa, Europe, and Asia. Based originally on numerous handaxes discovered at the site of St. Acheul (France), the term Acheulean is applied to stone assemblages with large bifacially flaked, ovoid tools. In an artifact assemblage, such tools must be abundant and/or finely made for the term to apply. In Africa, where the oldest Acheulean occurrences are known, handaxes and similar tools, such as cleavers and picks, are grouped under the term bifaces. Acheulean bifaces are highly standardized compared with flaked pieces of earlier non-Acheulean industries. It has been suggested that Acheulean sites in Africa are those where 40 percent or more of the intentionally flaked stones (i.e., tools or cores) are bifaces. However, sites where bifaces are fewer but are flaked carefully and symmetrically are also called Acheulean. In the view of some archaeologists, these criteria distinguish the Acheulean from other industries containing rare and crudely flaked bifaces, such as the Developed Oldowan or Clactonian. Still other researchers claim that, since the Acheulean is a tradition of tool manufacture involving the production of bifaces, any assemblage with such tools represents the Acheulean.
Preceded by the Oldowan and related core-flake tool kits, the Acheulean may have originated by gradual transition in the degree to which oval-shaped cobbles were flaked (chopper to protohandaxe to handaxe). Particularly in Europe, the idea of gradual refinement in tool manufacture from pre-Acheulean to Acheulean and throughout the Early Paleolithic period has been thought to involve a shift from using hammerstones in tool manufacture to “soft” hammers, such as bone or antler, which permit greater control over the transmission of force needed to remove a flake. It was suggested by G.L.Isaac, however, that the ability to remove large flakes (greater than 10cm in length) was essential to the emergence of the Acheulean in Africa. This ability may have represented a threshold in tool manufacture, rapidly exploited as a starting point in the manufacture of
bifaces. The rough oval shape of early bifaces is a natural extension of the original form of large flakes regardless of whether they had been further shaped intentionally into preconceived tools or simply used as cores for efficient production of sharp flakes. In Early Acheulean assemblages, such as those at Olduvai Gorge (Tanzania), it is nonetheless true that bifaces were sometimes made on cobbles and also on flakes smaller than 10cm. Thus, it is still unclear whether the manufacture of Acheulean bifaces came about by gradual refinement in the flaking of cobbles or by a technical refinement in the ability to produce large flakes.
Acheulean bifaces represent the distinctive product of early human technology during a period exceeding 1Myr. Studies of sequences of sites from individual localities, such as Olorgesailie (Kenya), have shown that handaxe manufacture and the overall makeup of Acheulean assemblages are marked by conservative, nonprogressive variation over hundreds of thousands of years. Moreover, examples of bifaces from Africa, Europe, and Asia are remarkably similar to one another, despite the great distances between localities. Biface forms nevertheless did undergo refinement over the time span of the Acheulean. In the early Acheulean, handaxes and related tools were chunky in section, with one face flatter than the other. The striking platforms of large flakes and the cortex of large cobbles were not necessarily removed entirely, resulting in asymmetrical handaxes. By the end of the Acheulean, very sophisticated handaxes were often made; flat and symmetrical in shape, they required great skill to produce. Elaborate core-preparation (e.g., Levallois) techniques, characteristic of Middle Paleolithic industries, were employed in producing highly refined bifaces in the latest Acheulean. Although many Late Acheulean assemblages exhibit refined skills in toolmaking, others are characterized by crude bifaces and bold flaking, typical of the Early Acheulean. Indeed, many factors affected the degree of sophistication of bifaces, including the raw material used. Overall change in the Acheulean is reflected by the fact that no Early Acheulean assemblage is known to be as refined as some Late Acheulean tool kits.
Lithic assemblages referred to as chopper-chopping tool industries are also known from the same time period throughout the Old World. These tool kits are typified by basic core-and-flake technology and tend to lack handaxes. Examples include the Clactonian in northern Europe, the Buda industry represented at Vértesszöllös (Hungary), and the Zhoukoudian industry in China. It is unknown whether these assemblages represent a distinct tradition of tool manufacture, geographic variants of the Acheulean, or, in some cases, an integral part of this industry. For example, it has been claimed that Clactonian assemblages reflect stages in the production of Acheulean tools. Other evidence suggests that biface and nonbiface assemblages are found in different habitats in the same area, as at Olorgesailie, and perhaps reflect different activities carried out by the same people. On the other hand, it is clear that assemblages in certain geographic regions, expecially in eastern Asia, simply are not characterized by bifaces.
At many Acheulean sites, bifaces occur in extremely dense concentrations in fluvial contexts. The behavioral interpretation of these sites is problematic due to the long time typically represented by fluvial strata and the possibility of winnowing of small flakes, leaving the heavier bifaces behind. While some Acheulean sites thus represent long periods of lag accumulation (similar to cobble bars in a stream), others appear to reflect the systematic deposition by hominids of handaxes near channels and of scraper-flake assem blages in floodplains away from the channel axis. The behavioral reasons for this pattern are unknown.
It is widely assumed that most Acheulean assemblages were manufactured by populations of Homo erectus. Fossils of H. erectus, however, are only rarely associated with Acheulean tools (e.g., at Tighenif [Algeria], Olduvai, and perhaps Swartkrans [South Africa]). In Africa, the oldest occurrences of the Acheulean (e.g., Konso and Olduvai middle Bed II) are in the time range of H. erectus (e.g., Olduvai Hominid 9). But
after 700Ka, they also occur at sites (e.g., Saldanha [South Africa], Ndutu [Tanzania], Bodo [Ethiopia]) yielding fossils often assigned to archaic Homo sapiens. In Europe, Acheulean assemblages first occur soon after 0.5Ma. Acheulean tools persist alongside early H. sapiens populations in Europe (e.g., at Swanscombe) and Africa until they are succeeded by Middle Paleolithic tool kits ca. 250–150Ka.
It is further assumed that these Acheulean toolmakers were hunter-gatherers who ranged widely for food. In fact, little is really known about the specific behavior and ecology of these hominids—for instance, whether they hunted big game or how they used their environments. Despite the prevalence of handaxes over an enormous time span, little is known about how they were used. One study of microscopic edge wear has shown that European handaxes were sometimes employed in butchery activities, and associated flakes also showed signs of working wood, hide, and bone. At other sites (e.g., an elephant skeleton and associated lithics excavated at Olorgesailie), handaxes evidently served as the cores for sharp flakes used in butchery. Experimental studies have indicated that bifaces are excellent all-purpose tools; their widespread distribution over much of the Paleolithic appears to bear this out.
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