Late Acheulean

(Elandsfontein Cutting 10)

Figure 4.5

An early Acheulean cleaver from Sterkfontein Cave and a late Acheulean cleaver from Elandsfontein Cutting 10 (top redrawn after K. Kuman 1994, Journal of Human Evolution 27, fig. 6; bottom drawn by T. P. Volman from the original).

and belonged "to a very ancient period indeed, even beyond the present world." Frere's archeological colleagues largely ignored his opinion, and it was the French customs official Boucher de Perthes who first forced the issue. Between about 1836 and 1846, de Perthes collected hand axes and bones of extinct mammals from ancient gravels of the Somme River near the town of Abbeville in northern France. He concluded that "In spite of their imperfection, these rude stones prove the [ancient] existence of man as surely as a whole Louvre would have done." His claims were initially spurned, but they gained credibility in 1854 when Dr. Rigollot, a distinguished and previously vocal skeptic, began finding similar flint axes in gravels near St. Acheul, a suburb of Amiens. In 1858, the eminent British geologist Joseph Prestwich visited Abbeville and St. Acheul to check the claims for himself. He came away convinced, and the case was made. Archeologists subsequently assigned ancient tool assemblages with hand axes to the Acheulean Culture or Industry, named for the prolific locality at St. Acheul. Later, when similar artifacts were recognized in Africa, they were also assigned to the Acheulean, and we now know that the Acheulean was present in Africa long before it reached Europe.

The oldest known Acheulean tools are dated to 1.65 million years ago, and they come from the same west Turkana region of northern Kenya that provided the Turkana Boy, though not from the same site. Acheulean artifacts are also well documented at 1.5 to 1.4 million years ago at Konso in southern Ethiopia, on the Karari Escarpment east of Lake Turkana in northern Kenya, and at Peninj near Olduvai Gorge in northern Tanzania. In each case, potassium/argon dating has verified their antiquity just as securely as it demonstrates the presence of ergaster by 1.8 to 1.7 million years ago, and the close correspondence between the oldest ergaster and the oldest Acheulean is probably not coincidental. Peninj has provided a lower jaw of the robust australopith, Paranthropus boisei, but this shows only that boisei persisted after ergaster emerged, not that boisei made Acheulean tools. Konso has provided an upper third molar and the left half of a lower jaw with four teeth from ergaster, and ergaster is the more likely tool maker. This is not only because it had a larger brain than boisei, but because Acheulean tools continue on largely unchanged after one million years ago, when boisei had become extinct.

The Acheulean surely originated from the Oldowan, and the oldest Acheulean assemblages often contain numerous Oldowan-style core forms and flakes alongside Acheulean hand axes. In a broad sense, the Oldowan core forms anticipate Acheulean bifaces, but no Oldowan or Acheulean assemblage contains tools that are truly intermediate between the two, and the biface concept seems to have appeared very suddenly in a kind of punctuational event like the one that may have produced ergaster. The earliest biface makers made one other noteworthy discovery that was often tied to biface manufacture—they learned how to strike large flakes, sometimes a foot or more in length, from large boulders, and it was from these that they often made hand axes and cleavers. Ancient stone tool assemblages that contain large flakes can be assigned to the Acheulean even on those occasions when, perhaps by chance, the assemblages lack hand axes.

The term hand axe implies that each piece was hand-held and used for chopping. Nonetheless, many hand axes are far too large and unwieldy for this, and their precise use remains conjectural. The puzzle is height ened at sites like Melka Kunture in Ethiopia, Olorgesailie in Kenya, Isimila in Tanzania, and Kalambo Falls in Zambia, where hand axes occur by the hundreds, often crowded close together and with no obvious signs of use. Such sites have prompted archeologists Marek Kohn and Steven Mithen to propose that the hand axe may have been the Acheulean equivalent of a male peacock's plumage—an impressive emblem for attracting mates. When a female saw a large, well-made biface in the hands of its maker, she might have concluded that he possessed just the determination, coordination, and strength needed to father successful offspring. Having obtained a mate, a male might simply discard the badge of his success, alongside others that had already served their purpose.

The mate selection hypothesis cannot be falsified, but sites with large concentrations of seemingly unused hand axes are less common than ones where hand axes are rarer and sometimes do show signs of use. Since the tools come in a wide variety of sizes and shapes, the probability is that they served multiple utilitarian functions. Some of the more carefully shaped, symmetric examples may have been hurled at game like a discus; other more casually made pieces may have served simply as portable sources of sharp-edged flakes; and yet others could have been used to chop or scrape wood. Experiments have also shown that hand axes make effective butchering tools, particularly for dismembering the carcasses of elephants or other large animals. The truth is that hand axes may have been used for every imaginable purpose, and the type probably had more in common with a Swiss Army knife than with a peacock's tail.

Once in place, the Acheulean Industry was remarkably conservative, and it is often said that it persisted largely unchanged from its inception at roughly 1.65 million years ago until its end at about 250,000 years ago. Harvard archeologist Glynn Isaac, who analyzed the Acheulean artifacts from a deeply stratified sequence at Olorgesailie, Kenya, remarked that the Acheulean displays a "variable sameness" and strikes "even enthusiasts as monotonous." By "variable sameness" he meant that changes in hand axe form from layer to layer or time to time seem to have been largely random and there is no obvious directional trend. Often, where hand axes in one assemblage appear more refined than they do in another, the reason may be that the people had different raw materials at their disposal. Flint or chert, for example, is usually much easier to flake than lava, and where people could get large enough pieces of flint, their hand axes will tend to appear more finely made for this reason alone.

Still, despite the apparent sameness over long periods, early and late Acheulean artifact assemblages do differ in some important respects. Early Acheulean hand axes tend to be much thicker, less extensively trimmed, and less symmetrical (Fig. 4.4). They were commonly shaped by fewer than 10 flake removals, and the flake scars were usually deep. Modern experiments indicate that such scars result from the use of "hard" (meaning stone) hammers. Later Acheulean hand axes are sometimes equally crude, but many are remarkably thin and extensively trimmed, and they are highly symmetric not just in plan form but also when viewed edge on. The final flake scars are shallow and flat, and replication efforts indicate that they were probably produced with "soft" (wooden or bone) hammers.

In addition, later Acheulean hand axes are often accompanied by more refined flake tools that anticipate those of the (Mousterian and Middle Stone Age) people who succeeded the Acheuleans. Like their

Figure 4.6

Stages in the manufacture of a classic Levallois flake whose size and shape have been predetermined on the core (redrawn after F. H. Bordes 1961, Science 134, fig. 4).

Figure 4.6

Stages in the manufacture of a classic Levallois flake whose size and shape have been predetermined on the core (redrawn after F. H. Bordes 1961, Science 134, fig. 4).

successors, later Acheuleans also knew how to prepare a core so that it would provide a flake of predetermined size and shape (Figure 4.6). Archeologists call such deliberate core preparation the Levallois technique, named for a western suburb of Paris where prepared cores were found and recognized in the latter part of the nineteenth century. The term Levallois refers strictly to a method of stone flaking, not a culture or tradition, and Levallois flaking was practiced by people of various cultures or traditions, including especially the late Acheuleans and their immediate successors. At any given time, people in some places employed the technique frequently, while people in others hardly used it at all. Most of the variation probably reflects differences in the availability of suitable stone raw material.

Most Acheulean assemblages are only weakly dated within the long Acheulean timespan, but future research may show that there were actually two periods of Acheulean stability, representing the early and late Acheulean respectively. They may have been separated by a short burst of relatively rapid artifactual change roughly 600,000 years ago that resulted in the more refined hand axes of the late Acheulean and that may have coincided with a relatively abrupt increase in human brain size.

We have already noted that Homo ergaster was the first human species to expand from Africa, but the timing of its dispersal is controversial. To understand why, we must back up a little and address the discovery and dating of its east Asian descendant, Homo erectus. The story begins with the Dutch physician and visionary Eugène Dubois.

Dubois was born in 1858, a year before Darwin published his signal classic On the Origin of Species, in which he showed how natural selection could drive evolutionary change. Dubois developed a passion for human evolution, and he became the first professional paleoanthropologist when he decided to search full time for human fossils. He focused on Indonesia, which was then a Dutch colony and which he and others reasoned was a logical place to start, since it still contained apes that might broadly resemble protohumans. He obtained a medical appointment in the Dutch East India Army, and he arrived in

Hoxnef

Abbeville & St. Acheul _

Gran Dolina~

Buia

Melka Kunturé Konso^ lNariokotome the "Movius line" marking the approximate eastern limit of the Acheulean (hand axe) Dmanisi Industrial Tradition

Yiyuan Nihewan a \ Zhoukoudian • \ ( Lantian • . , Yunxian Hexian ove

Ubeidiya

KoobiFora 0 -Olorgesailie Olduvai & Peninj

Ubeidiya

Nanjing

Kalambo Falls -,

Kathu Pan% Elandsfontein

Isimila (

KoobiFora 0 -Olorgesailie Olduvai & Peninj

Sterkfontein & Swartkrans

Sangiran, Sambungmachan, Ngandong, Trinil & Mojokerto

Nanjing

Sangiran, Sambungmachan, Ngandong, Trinil & Mojokerto

Figure 4.7

Locations of the sites mentioned in this chapter.

Indonesia in December 1887. He started his quest immediately, and in October 1891, he hit pay dirt in river deposits near the village of Trinil on the Solo River in central Java (Figure 4.7). Here, together with bones of ancient animals, he found a low-domed, angular, thick-walled human skullcap with a large shelf-like browridge. In August 1892, in what he thought were the same deposits, he recovered a nearly complete human thigh bone that was fully modern in every anatomical respect. The thigh bone and the skullcap convinced him that he had discovered an erect, ape-like transitional form between apes and people, and in 1894, he decided to call it Pithecanthropus erectus ("erect ape man"). It was later transferred to Homo erectus by scientists who benefited from a much fuller fossil record and a more contemplative approach to the use of species names. The implication of the transfer was that erectus did not differ from living people (Homo sapiens) as much as Dubois believed. The change in naming is partly a matter of taste, however, and the truly important point is that erectus was far removed from its ape ancestors in both anatomy and time.

Dubois's claim for Pithecanthropus met broadly the same kind of resistance that Dart's claim for Australopithecus did thirty years later. Dubois was discouraged, and after his return to the Netherlands in 1895, he gave up the search for human fossils. He was fully vindicated beginning only in 1936, when G. H. R. von Koenigswald described a second skull of Pithecanthropus from Mojokerto in eastern Java. The Mojokerto specimen represented a child between the ages of 4 and 6, but it still exhibited incipient browridges, a flat, receding forehead, an angular (as opposed to rounded) rear profile, and other features that recalled Dubois's Trinil find. Then, between 1937 and 1941, von Koenigswald reported three additional partial adult skulls, some fragmentary lower jaws, and isolated teeth from Sangiran, about 50 kilometers (30 miles) up the Solo River from Trinil in central Java (Figure 4.8). Associated animal bones suggested that two of the Sangiran skulls were about the same age as the Trinil skull and that the third was somewhat older.

Between 1952 and 1977, the deposits at Sangiran produced three additional skulls, some skull fragments, and six partial lower jaws, and there have been sporadic discoveries since. The most recent is a skullcap that turned up in 1999 in a New York City shop that shelf-like browridge flat, fOÎÂ relatively long, foreheaa ioW braincas?

shelf-like browridge flat, fOÎÂ relatively long, foreheaa ioW braincas?

Skull And Bones 1952

rear of skull composed of two planes meeting at an angle 5 cm forwardly projecting jaws no chin

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