DOI 10.1007/s10437-015-9205-8 Post Print Version of article published as Chazan, Michael (2015) Technological Trends in the Acheulean of Wonderwerk Cave, South Africa, African Archaeological Review 32(4): 701-728 Technological Trends in the Acheulean of Wonderwerk Cave, South Africa Michael Chazan1,2 Abstract The assemblage of stone tools from P. Beaumont’s Excavation 1 at Wonderwerk Cave, Northern Cape Province, South Africa, provides a unique stratified sequence covering a large part of the Earlier Stone Age. A combination of cosmogenic burial age and paleomagnetic age dating provides limited chronometric constraint on this sequence. The Wonderwerk sequence provides evidence for the development of Earlier Stone Age technology in southern Africa that parallels the sequence known from East Africa. This paper presents a technological discussion of biface technology at Wonderwerk Cave as well as an overview of the associated lithic assemblage. Résumé L’assemblage lithique provenant des fouilles de P. Beaumont à la Grotte de Wonderwerk, Province du Cap du Nord, Afrique du Sud, présente une séquence stratifiée unique couvrant la plupart du Earlier Stone Age. Un programme de datation par isotopes cosmogenique et paleomagnetisme nous donnes un dégrée du contraint chronométrique sur cette séquence. La séquence de Wonderwerk donne des indices d’un développement de la technologie au cours d’Earlier Stone Age en Afrique du Sud parallèle à la séquence connue en Afrique d’Est. Cette article présent une étude technologique des bifaces a Wonderwerk aussi bien qu’un vue d’ensemble 1 de l’assemblage lithique. Keywords Acheulean . Lithic technology. Earlier Stone Age . Wonderwerk Cave . Handaxe . Biface 1 Department of Anthropology, University of Toronto, 19 Russell St., Toronto, ONT M5S 2S2, Canada 2 Evolutionary Studies Institute, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, Johannesburg 2000, South Africa Introduction In 1969, Ray Inskeep raised a series of questions about the dynamics underlying culture change in the Earlier Stone Age of South Africa and came to the conclusion that: BThe answers to questions such as these depend almost entirely on progress in the field of chronology—and little progress has been made^ (Inskeep 1969, p. 175). Writing over 30 years later, Richard Klein reached a similarly pessimistic conclusion stating that Bthe bottom line is that the culture-stratigraphy and dating of the ESA in southern Africa depend heavily on extrapolation from eastern Africa^ (Klein 2000, p. 107). However, in recent years, research projects have begun to yield an independent chronostratigraphy for the Earlier Stone Age of southern Africa. At Rietputs on the Vaal River, a gravel unit associated with Acheulean artifacts produced a cosmogenic burial age of 1.57±0.22 mya, providing an age range of 1.8–1.4 mya for this industry (range of individual ages of samples 1.89±0.19 to 1.34±0.22 Ma (Gibbon et al. 2009)). At Cornelia-Uitzoek, an Acheulean industry along with associated fauna and a hominin tooth have been placed within the Jaramillo subchron (1.07–0.99 mya) on the basis of a well-developed paleomagnetic sequence (Brink et al. 2012). At Kathu Pan 1, a combination of ESR and OSL dating places an industry attributed to the Fauresmith and characterized by prepared core production of flakes and blades, including points apparently hafted on spears, at ca. 500 kyr (minimum OSL age of 464±47 kyr and a combined U- series–ESR age of 542+104–107 kyr: Porat et al. 2010; Wilkins and Chazan 2012; Wilkins et al. 2012). At Swartkrans, cosmogenic burial age dating of Member 1 produces ages ranging from 2.19±0.08 to 1.80±0.09 myr, indicating the likelihood that initial tool production falls within this time range (Gibbon et al. 2014). At Sterkfontein, there has been considerable debate and new data concerning the age of Members 2 and 4 with 3 implications for the age of the artifact-bearing components of overlying Member 5 (see Berger et al. 2002; Herries and Shaw 2011; Kuman and Clarke 2000; Pickering and Kramers 2010). The recent stratigraphic analysis of the Sterkfontein StW 573 Australopithecus fossil makes the complexity of the depositional environment apparent and provides reasons to treat the existing chronostratigraphic information with caution (Bruxelles et al. 2014). A cosmogenic burial age date on a single quartz manuport from Member 5 produced an age of 2.18±0.21 Myr (Granger et al. 2015). The chronostratigraphy of the Wonderwerk assemblage discussed in the following paragraphs, along with other recent results listed previously, raise questions about the likelihood that the artifact horizons at Sterkfontein are younger than 1.5 mya as has recently been proposed (Berger et al. 2002; Herries and Shaw 2011). Wonderwerk Cave Excavation 1 offers an opportunity to explore change over the entire extent of the Earlier Stone Age within a single depositional sequence. This aspect of the site is remarkable, and Wonderwerk Cave is the only site in the region with in situ deposits covering such a timespan. While the East African Rift research areas such as Konso, Olduvai, Melka Kunture, Gadeb, and Peninj have produced similar se- quences, none of these has the entire sequence represented at a single site (Beyene et al. 2013; de la Torre 2011; de la Torre et al. 2008; Diez-Martín et al. 2014; Domínguez-Rodrigo et al. 2009; Gallotti et al. 2010; Gallotti 2013; Kimura 2002; Leakey 1971; Leakey and Roe 1994). Notably, at Konso, a general sequence within the Acheulean has been recognized with a trend from unifacial to bifacial shaping with increasing refinement over time (Beyene et al. 2013). The Wonderwerk Excavation 1sequence provides an opportunity to test the applicability of the technological trends recognizable on East African sites to those in Southern Africa. Context Wonderwerk Cave is a phreatic tube that penetrates 140 m into the eastern flank of the Kuruman Hills. Overviews of the site are published elsewhere (Chazan et al. 2008; Horwitz and Chazan 2014, 2015, this issue), and the focus of this article is the Earlier Stone Age levels excavated by Beaumont beginning in 1978, in the area that begins ca. 30 m from the front of the cave designated as Excavation 1 (Beaumont and Vogel 2006). Earlier excavations by Malan (Malan and Cooke 1940; Malan and Wells 1943) reached the upper part of the Earlier Stone Age sequence, but this assemblage is not presented here. Beaumont’s excavation reached a total depth of 4 m below the surface of the cave across a maximum area of 62 sq.yds. Archaeological Strata Beaumont divided the Earlier Stone Age sequence into seven strata, St. 12-6 (bottom to top). Stratum 5 still contains a significant component of handaxes but seems to mark the contact between the Earlier Stone Age and the overlying Later Stone Age (there is no Middle Stone Age in Excavation 1). Within the strata, material was recovered by Beaumont from 1-×-1-yd units (maintaining the original grid established by Malan) excavated by arbitrary 10 cm spits. All materials have been curated in the McGregor Museum with associated contextual information, in most cases marked directly on the tools. One significant limitation is that depth of spits is measured not from a site datum, but rather is measured down from the top of an archaeological stratum in each particular square. Because there is a dip to the strata (Fig. 1) and no absolute heights were recorded for the top of each stratum across the excavation area, there are limits to our ability to reconstruct vertical provenience for artifacts. The limits of strata up to the top of Stratum 9 were marked by tags secured by nails in the northern section (confirmed on-site by Beaumont) that have served as the basis for our program of cosmogenic burial age and paleomagnetic dating (Chazan et al. 5 2012a; Matmon et al. 2012). This program has resulted in a chronological framework for Excavation 1, although as discussed in the following, there are still some gaps in chronological control. It is very significant that, with one exception, the sequence of seven cosmogenic burial age dates from the Excavation 1 sequence are in stratigraphic order, and for the one anomaly, the correct age is within one standard deviation. These dates provide support for the extensive micromorphological record that indicates that Excavation 1 is a depositional context that is only disturbed by bioturbation, of a scale that was not likely to result in significant vertical displacement of artifacts (Goldberg et al. 2015, this issue). Micromorphological analysis also indicates that there was no high-energy transport within this sequence and that artifacts found in the cave had to be transported by hominins. Although the sequence developed over a very long duration, there is no reason to believe that deposition was continuous, and there is clear evidence of erosional events within the sequence. Chronostratigraphy The age of the depositional sequence at Wonderwerk Cave is constrained by a combination of paleomagnetic and cosmogenic burial age dating. From a technical perspective, the quality of the chronostratigraphic determinations is very high. It is important to emphasize that these are dating methods based on independent physical processes. Paleomagnetic dating is limited in that it only allows a determination of whether sediments were deposited during normal or reversed polarity events. In the Wonderwerk profile, there is a clear patterning shown in Table 1 (see complete presentation in Chazan et al. 2008; Matmon et al. 2012). Paleomagnetic dates give us a set of candidate time intervals for a depositional sequence. In the case of Wonderwerk Excavation 1, there is a sequence of N-R-N that potentially can be correlated with a number of paleomagnetic intervals in the Cenezoic.