Kathy Schick

The evolution and cultural transmission of percussive technology: integrating evidence from palaeoanthropology and primatology☆

We bring together the quite different kinds of evidence available from palaeoanthropology and primatology to better understand the origins of Plio-Pleistocene percussive technology. Accumulated palaeoanthropological discoveries now document the Oldowan Complex as the dominant stone tool making culture between 2.6-1.4 Ma, the earlier part of this contemporaneous with pre-Homo hominins. The principal types of artefacts and other remains from 20 Early Stone Age (Oldowan and earliest Acheulean) localities in Africa and elsewhere are reviewed and described. To better understand the ancestral behavioural foundations of this early lithic culture, we examine a range of recent findings from primatology. In particular, we attempt to identify key shared characteristics of Homo and Pan that support inferences about the preparedness of our common ancestor for the innovation of stone tool culture. Findings of particular relevance include: (i) the discovery of an expanding repertoire of percussive and other tool use based on directed use of force among wild chimpanzees, implicating capacities that include significant innovatory potential and appreciation of relevant causal factors; (ii) evidence of material cultural diversity among wild chimpanzees, indicating a readiness to acquire and transmit tool use innovations; and (iii) experimental studies of social learning in chimpanzees and bonobos that now encompass the acquisition of nut cracking through observation of skilled use of hammers and anvils by conspecifics, the diffusion within and between groups of alternative styles of tool use, and the adoption of free-hand stone-to-stone percussion to create useful flakes for cutting to gain access to food resources. We use the distributions of the inferred cultural traits in the wild to assess how diffusion relates to geographic distances, and find that shared traits drop by 50% from the approximately eight characteristic of close neighbours over a distance of approximately 700 km. This pattern is used to explore the implications of analogous processes operating in relation to Early Stone Age sites.

Archaeological perspectives in the Nihewan Basin, China

Abstract Paleolithic archaeological sites in the Nihewan Basin (previously Nihowan) in northern China were visited and their excavated materials examined in order to assess their potential for future research. Paleomagnetic studies have indicated that the older sites here may extend back to the late Early Pleistocene (ca. 1 m.y.a.); radiocarbon dates for the later sites indicate later Late Pleistocene age (ca. 11,000 B.P.). Previous work has found the earlier sites in the sedimentary seqeunce to be contained within magnetically reversed sediments believed to lie below the Jaramillo Subchron (ca. 0·97 m.y.a.), and thus they may represent some of the earliest occupations ofHomo erectus in eastern Asia. The stratigraphic contexts of these sites were examined in the field, excavated artefacts were studied in the laboratory, and preliminary artefact replication experiments were carried out. Artefact assemblages at the earlier sites are made primarily in local cherts and are technologically simple industries predominated by unmodified flakes and fragments, with some flaked cobbles and chunks but relatively few modified or retouched pieces. Most of the sites are in fine-grained sediments indicating low-energy conditions of deposition in fluvial/lacustrine environments, and their artefacts are in very good, fresh condition; thus they may preservein situ evidence of activity patterns. An in-depth analysis is being conducted of Donggutuo, one of the earlier sites. Preliminary results of this study indicate good potential for conjoining of flaked artefacts, microwear analysis, analysis of cut-marked and carnivore-gnawed bone, and intrasite spatial studies of possible activity patterns ofHomo erectus in eastern Asia in the Early Pleistocene.

PALEOECOLOGIC SIGNIFICANCE OF MALACOFAUNA, OLDUVAI GORGE, TANZANIA

Abstract The rich record of vertebrate, hominin and archaeological remains recovered from Olduvai Gorge in northern Tanzania stands in stark contrast to the largely unexplored macroinvertebrate record from the region. Here we examine fossil malacofauna from Olduvai Gorge, inclusive of new discoveries and previous reports, and survey their potential as paleoecologic indicators. Recorded for the first time from Olduvai, an assemblage of fossil bivalve shells is attributed by character comparison to modern Chambardia wahlbergi, a freshwater unionid species widespread across Africa. The fossilized shells were localized in Bed III conglomerate channel deposits, with channel geometry exhibiting scour bases and superimposed fill structures with fining upward sequences. The ecology of recent C. wahlbergi combined with sedimentological data indicate the aquatic environment in this region during Olduvai Bed III times can be reconstructed as a periodically desiccated floodplain bordering a river channel or channels with permanent running water and marked seasonal fluctuations. This paleo-environmental setting presents drastic change compared with that of the lower Bed I and Bed II deposits, when an alkaline/saline lake extended over the site and fresh water was restricted to standing groundwater-fed pools with snail species known today to be intermediate hosts for the trematode genera Schistosoma (schistosomiasis) and Fasciola (fascioliasis). This research enhances details of landscape evolution at Olduvai basin and furthers paleoenvironmental interpretations during the time of Bed III deposition.