A chronological framework for a long and persistent archaeological record: Melka Kunture, Ethiopia

New ⁴⁰Ar/³⁹Ar geochronological data for several volcanic ash horizons from Melka Kunture, Ethiopia, allow for significantly more precise age constraints to be placed upon the lithostratigraphy, archaeology and paleontology from this long record. Ashes from the Melka Kunture Formation at Gombore yielded the most reliable age constraints, from 1.393 ± 0.162 Ma² (millions of years ago) near the base of the section to 0.709 ± 0.013 Ma near the top. Dating the Garba section proved more problematic, but the base of the section, which contains numerous Oldowan obsidian artifacts, may be >1.719 ± 0.199 Ma, while the top is securely dated to 0.869 ± 0.020 Ma. The large ignimbrite from the Kella Formation at Kella and Melka Garba is dated to 1.262 ± 0.034 Ma and pre-dates Acheulean artifacts in the area. The Gombore II site, which has yielded two Homo skull fragments, ‘twisted bifaces,’ and a preserved butchery site, is now constrained between 0.875 ± 0.010 Ma and 0.709 ± 0.013 Ma. Additional ashes from these and other sites further constrain the timing of deposition throughout the section.Integration with previously published magnetostratigraphy has allowed for the first time a relatively complete, reliable timeline for the deposition of sediments, environmental changes, archaeology, and paleontology at Melka Kunture.     

The Unknown Oldowan: ~1.7-Million-Year-Old Standardized Obsidian Small Tools from Garba IV,Melka Kunture,Ethiopia

The Oldowan Industrial Complex has long been thought to have been static, with limited internal variability, embracing techno-complexes essentially focused on small-to-medium flake production. The flakes were rarely modified by retouch to produce small tools, which do not show any standardized pattern. Usually, the manufacture of small standardized tools has been interpreted as a more complex behavior emerging with the Acheulean technology. Here we report on the ~1.7 Ma Oldowan assemblages from Garba IVE-F at Melka Kunture in the Ethiopian highland. This industry is structured by technical criteria shared by the other East African Oldowan assemblages. However, there is also evidence of a specific technical process never recorded before, i.e. the systematic production of standardized small pointed tools strictly linked to the obsidian exploitation. Standardization and raw material selection in the manufacture of small tools disappear at Melka Kunture during the Lower Pleistocene Acheulean. This proves that 1) the emergence of a certain degree of standardization in tool-kits does not reflect in itself a major step in cultural evolution; and that 2) the Oldowan knappers, when driven by functional needs and supported by a highly suitable raw material, were occasionally able to develop specific technical solutions. The small tool production at ~1.7 Ma, at a time when the Acheulean was already emerging elsewhere in East Africa, adds to the growing amount of evidence of Oldowan techno-economic variability and flexibility, further challenging the view that early stone knapping was static over hundreds of thousands of years.     

Une vue d’ensemble sur Melka Kunture,grand complexe de sites pléistocènes dans la vallée supérieure de l’Awash (Éthiopie)

Melka Kunture is a cluster of Pleistocene sites, extending over ?100 km² between 2000 and 2200 m asl, in the upper Awash Valley of Ethiopia. Starting around 2 million-years ago, the archaeological sequence includes sites with lithic productions of the Oldowan, Early Acheulean, middle Acheulean, final Acheulean, Early Middle Stone Age, Middle Stone Age and Late Stone Age. All over the Pleistocene, the climate was rainy and cooler than at the lower elevations of the Rift Valley, allowing the development of Afromontane vegetation. Hippopotamuses are ubiquitous and dominant in terms of biomass, but Alcelaphini are well represented, notably with genus Connochaetes and genus Damaliscus. Hominin fossils have been discovered in association with the Oldowan, the Early Acheulean, the middle Acheulean and the Early Middle Stone Age. Animal tracks and hominin footprints have also been documented, the latter ones in layers dated between 1.2 and 0.7 million-years.     

Evidence of amelogenesis imperfecta in an early African Homo erectus

The teeth of the Homo erectus child (Garba IV) recovered from Melka Kunture Ethiopia and dated to 1.5 Ma are characterized by generalized enamel dysplasia, reduced enamel radio-opacity, and severe attrition. This combination of features is found in a large group of hereditary, generalized enamel dysplasias known as amelogenesis imperfecta (AI). SEM studies carried out on epoxy replicas of teeth from the Garba IV child, confirmed that the defects noted were developmental and not due to diagenesis. The enamel prism arrangement is abnormal and there are deep vertical furrows lacking enamel on both buccal and lingual surfaces of all molars. The lesions differ from those characteristic of linear enamel hypoplasia that form discrete horizontal lesions or pits within otherwise normal enamel. We propose that the Garba IV child is the earliest example of AI and provides a link between palaeoanthropology and molecular biology in investigations of the evolutionary history of genetic disorders.     

The Early Stone Age lithic assemblages of Gadeb (Ethiopia) and the Developed Oldowan/early Acheulean in East Africa

The Early Stone Age sites of Gadeb (Ethiopian South-East Plateau) were excavated under the direction of Desmond Clark in the 1970s. Dated to between 1.45 and 0.7 Ma, Gadeb proved that humans had already occupied high altitude areas in the Lower Pleistocene. Despite the importance of the Gadeb sites, their lithic assemblages were never published in detail, and no review of the stone tools has ever been reported since the original 1970s study. This paper updates the information available on Gadeb by presenting a systematic review of the lithic technology of several assemblages. The objectives are to evaluate the technological skills of Gadeb knappers and to contextualize them into the current discussion of the origins of the Acheulean and its possible coexistence with the so-called Developed Oldowan in East Africa.     

Le Paléolithique ancien de l’Europe orientale et du Caucase

Currently, only Tréhougol’naya Cave has reliably dated evidence for human settlement in Eastern Europe and Caucasus, from the beginning through the middle of the Middle Pleistocene. In Eastern Europe, assemblages from Khriatchi and Mikhailovskoé, and possibly Darvagchai I, appear to be the only stratified locations that tentatively can be compared (despite problems with these materials) with Tréhougol’naya. In the eastern limits of Central Europe, layer VI in Korolevo I is the only stratified assemblage that may be compared with Tréhougol’naya. All these Lower Paleolithic occupations yielded the Pre-Mousterian small tool industries with some pebble tools, but without Acheulean bifaces and Levallois technique. These data suggest that Eastern Europe lies outside the distribution range of the Acheulean techno-complex demarcated with the “Movius Line”. In the Southern Caucasus, the Dmanissi hominine and lithic records document the fact that the earliest small-brained humans – probably later H. habilis-rudolfensis or earlier H. ergaster-erectus hominids bearing Pre-Oldowan technology – initially left Africa and appeared in Western Asia as early as 1.8 Ma ago. However, in the Southern Caucasus, the available chronological data indicate that the Acheulean complex has a later temporal appearance here compared to the Upper Acheulean or Acheulo-Yabrudian in Western Asia. Two main Upper Acheulean industrial variants currently can be recognized in the Southern Caucasus. The first, called the Kudarian by the author (from the caves of Kudaro I, Kudaro III, and Azyk), is characterized by lithics made from mostly siliceous rocks, rare Acheulean bifaces, and non-Levallois flaking technique. The second variant is characterized by lithics made from volcanic rocks, numerous Acheulean bifaces, and often more laminar or Levallois debitage. It can be suggested that there are independent origins for these Southern Caucasus Upper Acheulean industrial variants. Possible roots of the Acheulean assemblages of Kudarian variant might be in the local earlier Lower Paleolithic small tool assemblages with some pebble tools but without Acheulean bifaces. The other Caucasus variant of the Upper Acheulean appears to be related to the Levantine Upper Acheulean.     

Découverte des sites du Paléolithique inférieur au Nord de l’Arménie

For a long time, the scientific community assumed that the Acheulean culture was expressed on the territory of the Armenian Plateau as well as in the neighboring regions of the Caucasus only by its late phase; therefore, it appeared in the second half of the Middle Pleistocene. In recent years, the Armenian-Russian mission has discovered and studied much older Acheulean industries sites, located in northern Armenia (the Lori intermountain Depression). These industries, represented by archaic type tools (large hand axes, picks, choppers, chisel-like tools, scrapers, points, etc.), are discovered in three deposits of origin of proluvial genesis. In the Karakhach site, this type of industry is deposited in the lower levels of volcanic tuff and below; the U/Pb study of this level of tuff proposes a series of dates, assigned to the time interval between 1.944 + 0.046 and 1.75 + 0.02 Ma. The paleomagnetic study demonstrated the inverse polarity on the tuff and the normal polarity of the underlying deposits; in correlation with other dating, this fact allows to attribute the Acheulean layers of the site of Karakhatch to the Lower Pleistocene, in particular to the Oldoway episode and to the Upper Matuyama time period. The estimated age and the techno-morphological characteristics of the tools indicate the Lower Acheulean period. The dating of the Muradovo site does not seem possible, however its very old industries and the archaeological layers, where they were discovered, find equivalents in the layered layer, surmounted by tuffs, of the Karakhatch site. The Kutran I site presented a paleosol sequence with similar Acheulean tools (hand axes, picks, choppers, etc.). Its oldest layer is older than 1.5 Ma, the upper layer is attributed to the early Middle Pleistocene; this fact means that it is possible to speak of the Lower Acheulean and of its transition to the Middle Acheulean period. The specific character and the age of the Lower Acheulean of Armenia admit that it could have formed independently of the Lower Acheulean of Africa, whose estimated age does not rise before 1.76 Ma. It should also be noted that on the neighboring territory of Georgia about the same time when appeared the Acheulean culture in Armenia, the Oldowan Dmanisi site already existed.     

Les industries archaïques au Proche-Orient

The Middle East (from the Mediterranean coast to Iran and from the Red Sea to the Black Sea) is located at the crossroads of African, Asian and European continents. It is a compulsory route well-trodden during the dispersal of the first humans out of Africa. Recent discoveries, mainly in Syria, Jordan and Israel, show that the first settlements in this area date back to over 2 million years (Ma). The location of the deposits containing archaic industries of the Oldowan type in the broad sense, often called “Core and Flake Industries”, indicates that several roads have been repeatedly used to connect Egypt and the Arabian Peninsula with the Euphrates and the Tiger basins. From south to north, if the coastal road and the tectonic depression of the Dead Sea, the Jordan Valley and the Beqaa were privileged places of very old settlements, the desert roads through Jordan and Syria were also readily used even before 2 Ma. We can observe at least three successive stages of archaic industries. During the oldest one, from about 2.5 to 1.8 Ma, choppers, chopping-tools, cores and flakes are prevailing without traces of intentional retouching (Sites of Aïn Al Fil in Syria, of the Zarqa Valley in Jordan in particular). This period might be named Pre-Oldowan or Lower Oldowan. From approximately 1.8 to 1.3 Ma, a similar culture developed with the additional presence of regular polyhedrons and sometimes a rough bifacial shaping as well as the beginning of rare intentional retouching other than that of use-wear; we will call it Upper Oldowan (Lower G-Hummal in Syria, Bizat Ruhama and Lower Ubeidiya in Israel). Starting around 1.3 Ma, coarse bifaces begin to appear, always knapped with a stone hammer. This technology points to the transition towards Acheulean industries. The first bifaces appeared within a very Oldowan technological background (Hummal, Ubeidiya). However, in the Levant, sites often considered as “pre-Acheulean” because they lacked bifaces, though they belonged to more recent periods, younger than 1.3 Ma, have been termed “Tayacian” in order to underline their difference from Acheulean properly speaking. They seem contemporary with the first Acheulean phases and could correspond to a final Oldowan. The question remains, however, whether these are non-Acheulean cultures or “Acheuleans without bifaces”.     

Radiometric dating of the Earlier Stone Age sequence in excavation I at Wonderwerk Cave, South Africa: preliminary results

We present here the results of 44 paleomagnetic measurements, and single cosmogenic burial and optically stimulated luminescence ages for the Earlier Stone Age deposits from Wonderwerk Cave, Northern Cape, South Africa. The resulting paleomagnetic sequence: N>R>N>R>N constrains the Earlier Stone Age strata in this part of the site to between approximately 0.78-1.96 Ma. A single cosmogenic date of approximately 2.0 Ma from the base of the section offers some corroboration for the paleomagnetic sequence. Preliminary results indicate that the small lithic assemblage from the basal stratum may contain an Oldowan facies. This is overlain by several strata containing Acheulean industries. The preliminary radiometric dates reported here place the onset of the Acheulean at this site to approximately 1.6 Ma, which is roughly contemporaneous with that of East Africa.     

Barogali et l’Oued Doure. Deux gisements représentatifs du Paléolithique ancien en République de Djibouti

In the Republic of Djibouti, surveys and excavations, carried out from 1985 to 1992, confirmed the presence of the pre-Acheulean (Oldowan) and Acheulean sites in the country. Three seasons of excavations (1985-1987 in the Gobaad Basin, have unearthed in a hardened compact clay strata of an ancient marshland dating to the Lower Pleistocene, the fossilized skeletal remains of an Elephas recki ileretensis. Numerous stone tools have been gathered with the bones. The E.S.R. dating the elephant’s lower third molar gave a date between 1,.6 and 1,.3 MY that would confirm its paleontological grouping and the membership of this butchery site to the Oldowan period. The animal appeared to have been lying on its left side. The cranial roof had been separated from the calvarium, perhaps to get at the brain; but the skull remains in anatomic connection with the tusks. The jaw (mandible) seems to have been broken to extract the tongue. Hominids, perhaps Homo ergaster, knapped tools from a nearly outcrop of poor quality lava. The tools were specifically adapted to their needs, such as scraping, chopping and scattering the bones. The site has yielded 569 artifacts: utilized material and hammerstones (121); pebble tools (32); cores (14); “debitage” products (366); retouched flakes (36). Artifacts are rarely retouched and often broken. Five different types of choppers have been classified. The polyedrons and one bola make up 22% of the pebble tools. The cores are divided into unipolar, centripetal and polyhedrical types. In another site, Haïdalo, an almost complete skeleton of an Elephas recki recki in anatomical connection and without any sign of predation, has been found at eight kilometers from Barogali. During surveys in the Ali Sabîh region (1990-1992) seven sectors have been discovered and prospected in the Oued Doure Basin. On the surface area and also in situ into some little pits, 345 rhiolitic Acheulean artifacts have been found, near rhyolitic outcrop. These artifacts are generally large. The choppers (18) can be dividended into 2 sets : side choppers (55%) and end choppers (27%), often with a bifacial cutting edge. There is only one polyedron, but we have found eight heavy scrapers. The Acheulean group is important (43 tools). The bifaces are varied and there are also a few cleavers and picks. Cores are numerous (92) and Levallois cores are preponderant (45%). We find also centripetal cores (27%) and so unipolar, bipolar and polyhedral cores. Tools made of flakes (118) are numerous: scrapers are typologically diversified. Some of them have a double utilization. Notch tools, denticulate tools are presents but also end scrapers, burin, borer, back knifes and scantily retouched flakes. The characters of this lithic material, large cores and big flakes, large bifaces of various types, cleavers and retouched flakes, indicates that they are Acheulean products. So, the Doure Site can be placed in the Middle / Upper Acheulean transition.     

Research on late Pliocene Oldowan sites at Kanjera South, Kenya

The late Pliocene is notable for the appearance of two new hominid genera as well as the first archaeological sites, generally attributed to the Oldowan Industrial Complex. However, the behavioral ecology of Oldowan hominids has been little explored, particularly at sites older than 2.0 Ma. Moreover, debates on Oldowan hominid foraging ecology and behavior have centered on data from only two regions, and often from single site levels. Here we describe the preliminary results of our investigation of Oldowan occurrences at Kanjera South. These occurrences preserve the oldest known traces of hominid activity in southwestern Kenya, and unlike most of the Oldowan sites in the 2.0-2.5 Ma time interval, artefacts are found in spatial association with a well-preserved fauna. In 1996 and 1997, this project initiated the first excavation program for Kanjera South. Magneto- and biostratigraphy indicate that deposition began approximately 2.2 Ma, substantially earlier than previously thought. At Excavation 1, artefacts were found in spatial association with a taxonomically diverse faunal assemblage in Beds KS-1 and KS-2. Excavation 2 yielded a partial hippopotamus axial skeleton with artefacts in KS-3. Cores from both sites were incidentally flaked and represent a Mode I lithic technology indistinguishable from the Oldowan. Approximately 15% of the artefacts were manufactured from non-local raw materials, indicating a flow of resources into the area. Stable isotopic analysis of KS-1 and KS-2 pedogenic carbonates suggests that the Excavation 1 assemblages formed in a relatively open (>75% C4 grass) habitat. The Excavation 1 and 2 faunas contain a high proportion of equids relative to Oldowan accumulations from Bed I Olduvai Gorge, Tanzania. Beds KS-1 and KS-2 thus preserve traces of Oldowan hominid activities in a more open setting than has been previously documented.     

The dating and interpretation of a Mode 1 site in the Luangwa Valley, Zambia

Flake based assemblages (Mode 1) comprise the earliest stone technologies known, with well-dated Oldowan sites occurring in eastern Africa between ∼ 2.6-1.7 Ma, and in less securely dated contexts in central, southern and northern Africa. Our understanding of the spread and local development of this technology outside East Africa remains hampered by the lack of reliable numerical dating techniques applicable to non-volcanic deposits. This study applied the still relatively new technique of cosmogenic nuclide burial dating (¹⁰Be/²⁶Al) to calculate burial ages for fluvial gravels containing Mode 1 artefacts in the Luangwa Valley, Zambia. The Manzi River, a tributary of the Luangwa River, has exposed a 4.7 m deep section of fluvial sands with discontinuous but stratified gravel layers bearing Mode 1, possibly Oldowan, artefacts in the basal layers. An unconformity divides the Manzi section, separating Mode 1 deposits from overlying gravels containing Mode 3 (Middle Stone Age) artefacts. No diagnostic Mode 2 (Acheulean) artefacts were found.Cosmogenic nuclide burial dating was attempted for the basal gravels as well as exposure ages for the upper Mode 3 gravels, but was unsuccessful. The complex depositional history of the site prevented the calculation of reliable age models. A relative chronology for the full Manzi sequence was constructed, however, from the magnetostratigraphy of the deposit (N>R>N sequence). Isothermal thermoluminescence (ITL) dating of the upper Mode 3 layers also provided consistent results (∼78 ka). A coarse but chronologically coherent sequence now exists for the Manzi section with the unconformity separating probable mid- or early Pleistocene deposits below from late Pleistocene deposits above. The results suggest Mode 1 technology in the Luangwa Valley may post-date the Oldowan in eastern and southern Africa. The dating programme has contributed to a clearer understanding of the geomorphological processes that have shaped the valley and structured its archaeological record.     

Oldowayen archaïque et Oldowayen classique de l’Afrique à l’Europe méditerranéenne

Analyzing lithic industries of Lower Pleistocene and beginning of Middle Pleistocene times allows to define three groups not clearly chronological but which reflect the cognitive evolution of prehistoric Men who knapped them and the constraints of the environment: - “Archaic Oldowan” industries in which raw flakes are dominant and no small tools retouched on flakes or debris are present; - “Classical Oldowan” industries in which raw flakes are dominant and small tools retouched on flakes and debris – especially scrapers – are present; - “Acheulean industries”, in which bifaces are present – generally in small proportions – and small retouched tools are increasingly standardized.     

New Oldowan localities at high level within Kilombe Caldera,Kenya

New occurrences of early artefacts ascribed to the Oldowan tradition come from localities at high level within the caldera of the extinct Kilombe volcano, located in the central rift valley of Kenya. The trachyte cone and caldera of Kilombe volcano formed at ca. 2.5 Ma, and the record of >130 m of sediment-fill indicates that the caldera subsequently held a lake for long periods during the Early Pleistocene. The Oldowan artefact localities, dated by ⁴⁰Ar/³⁹Ar and palaeomagnetism to ～1.78 Ma, lie east of the centre of the caldera, on the west side of an ancient small lake, which later drained away as a gorge formed on the east side of the mountain. The artefacts are dominantly made of Kilombe trachyte, and are associated with a fauna of large animals including Hippopotamus gorgops. These are the first Oldowan localities to be discovered in a new area of the Kenyan rift valley in the last thirty years, and their presence at high level in rugged landscape indicates that the associated hominins were exploiting a full range of environments.     

Étude préliminaire des industries archaïques de faciès Oldowayen du site de Hummal (El Kowm, Syrie centrale)

The spring site of Hummal is located in Central Syria, near the village of El Kowm between the Euphrates basin and the desert steppe stretching from Palmyra to Deir-ez-Zor. In 1966 the well was noted in a survey as Bir Onusi and a short preliminary study was carried out at the beginning of the 1980s. Since 1997, the Institute for Prehistory and Archaeological Science of the University of Basel has undertaken a complete interdisciplinary research program of this major site under the direction of J.M Le Tensorer, supported by the Swiss National Science Foundation and associated with the Directorate General of Antiquities and Museums of Syria under the direction of S. Muhesen. The site of Hummal is a prominent mound at an artesian spring built out of the sediments, which piled up during the whole Quaternary. Tectonic faults in the bed rock enabled the underlying water in a karstic system to flow out into a dolina, which trapped lacustrine, limnic and aeolian sediments since the Oldest Pleistocene. The impressive stratigraphy – 20 m high – comprises 23 geological units preserving a great number of archaeological levels. It covers an extremely long period of time ranging from the Oldest Palaeolithic (Oldowan) to Upper Palaeolithic (Aurignacian) over more than a million years. This impressive Old and Middle Palaeolithic sequence comprises several layers of Oldowan-like assemblage (23-16), an Acheuleo-Tayacian complex (14-13), five layers of Yabrudian (12-8) at least four levels of Hummalian (7, 6c, 6b, 6a) and a thick sediment complex with 8 Mousterian layers, each of them liable to be subdivided into several sublayers. The lithic industry in the lowest levels of the Hummal sequence, associated with abundant remains of large mammals, can be characterized by non-modified, quite fresh flakes, with, once in a while, traces of use but never bearing intentional retouches. Theses flakes are found with pebble-tools: choppers, chopping-tools, polyhedrons, bolas and core-like artifacts. This assemblage is typical in a broad sense of archaic Palaeolithic whose debitage corresponds to mode 1. From a techno-typological point of view, this industry tallies quite well with the so-called Oldowan stage. It shows remarkable similarities with the oldest assemblages at Ubeidiya but, so far, with no occurrence of bifacial knapping. If the layers 17 and 18 of Hummal relate to this period dating back to 1.6 to 1.2 million years, these levels would be the oldest ones ever found in central Syria. However, as we have no absolute dating at our disposal so far, we will remain careful in assigning a chronological time span for these layers. For this area, from a stratigraphic point of view, the Oldowan levels of Hummal occur before the Acheulean and certainly before the Acheulean sequence of El Meirah (region of El Kowm) which is itself related to the period before Matuyama-Brunhes paleomagnetic reverse. Dating of the lowest sequence of Hummal is underway. If we take into account stratigraphic and techno-typological observations, we assume that the Oldowan-like levels of the site should be older than one million years at least. The sequence of Hummal is one of the largest in the Near-East. Therefore, it can be regarded as a key-site for world prehistory.     

Technological variation in the earliest Oldowan from Gona,Afar, Ethiopia

Inter-site technological variation in the archaeological record is one of the richest potential sources of information about Plio-Pleistocene hominid behavior and evolution. However, appropriate methods for describing and comparing Oldowan assemblages have yet to be agreed upon, and interpretation of the early record remains highly controversial. Particularly salient is disagreement over whether the Oldowan is a single technological phenomenon or is more accurately divided into multiple regional and/or chronological traditions, perhaps including a less developed Pre-Oldowan phase in the late Pliocene. Some of this disagreement reflects theoretical and methodological differences between research traditions and some is more directly evidential. Here we present a framework for describing and interpreting Oldowan variation and apply it to three Pliocene assemblages (EG-10, EG-12, and OGS-7) from Gona, all dated to c. 2.6 million years (Ma). Results indicate proficient knapping and a full range of Oldowan reduction strategies in these earliest known occurrences, consistent with the idea of an Oldowan “technological stasis” from 2.6–1.6 Ma. Patterns of variation in raw material selection and predominant reduction strategy at each site clearly indicate the importance of cultural transmission in the Oldowan, but confounding ecological and economic variation continue to render interpretation in terms of multiple tool making traditions or species inappropriate. We propose that cultural transmission and ecological adaptation should be recognized as complementary, rather than mutually exclusive, mechanisms in future attempts to explain Oldowan technological variation.     

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.     

Stratigraphy, artefact industries and hominid associations for Sterkfontein, member 5

A revised stratigraphy for the early hominid site of Sterkfontein (Gauteng Province, South Africa) reveals a complex distribution of infills in the main excavation area between 2.8 and 1.4 m.y.a, as well as deposits dating to the mid to late Pleistocene. New research now shows that the Member 4 australopithecine breccia (2.8-2.6 Ma) extends further west than was previously thought, while a late phase of Member 4 is recognized in a southern area. The artefact-bearing breccias were defined sedimentologically as Member 5, but one supposed part of these younger breccias, the StW 53 infill, lacks in situ stone tools, although it does appear to post-date 2.6 Ma when artefacts first appear in the archaeological record. The StW 53 hominid, previously referred to Homo habilis, is here argued to be Australopithecus. The first artefact-bearing breccia of Member 5 is the Oldowan Infill, estimated at 2-1.7 Ma. It occupies a restricted distribution in Member 5 east and contains an expedient, flake-based tool industry associated with a few fossils of Paranthropos robustus. An enlarged cave opening subsequently admitted one or more Early Acheulean infills associated in Member 5 west with Homo ergaster. The artefacts attest to a larger site accumulation between ca. 1.7 and 1.4 Ma, with more intensive use of quartzite over quartz and a subtle but important shift to large flakes and heavier-duty tools. The available information on palaeoenvironments is summarized, showing an overall change from tropical to sub-tropical gallery forest, forest fringe and woodland conditions in Member 4 to more open woodland and grassland habitats in the later units, but with suggestions of a wet localized topography in the Paranthropus -bearing Oldowan Infill.     

Early Acheulean technology in the Rietputs Formation, South Africa, dated with cosmogenic nuclides

An absolute dating technique based on the build-up and decay of ²⁶Al and ¹⁰Be in the mineral quartz provides crucial evidence regarding early Acheulean hominid distribution in South Africa. Cosmogenic nuclide burial dating of an ancient alluvial deposit of the Vaal River (Rietputs Formation) in the western interior of South Africa shows that coarse gravel and sand aggradation there occurred ca 1.57 ± 0.22 Ma, with individual ages of samples ranging from 1.89 ± 0.19 to 1.34 ± 0.22 Ma. This was followed by aggradation of laminated and cross-bedded fine alluvium at ca 1.26 ± 0.10 Ma. The Rietputs Formation provides an ideal situation for the use of the cosmogenic nuclide burial dating method, as samples could be obtained from deep mining pits at depths ranging from 7 to 16 meters. Individual dates provide only a minimum age for the stone tool technology preserved within the deposits. Each assemblage represents a time averaged collection. Bifacial tools distributed throughout the coarse gravel and sand unit can be assigned to an early phase of the Acheulean. This is the first absolute radiometric dated evidence for early Acheulean artefacts in South Africa that have been found outside of the early hominid sites of the Gauteng Province. These absolute dates also indicate that handaxe-using hominids inhabited southern Africa as early as their counterparts in East Africa. The simultaneous appearance of the Acheulean in different parts of the continent implies relatively rapid technology development and the widespread use of large cutting tools in the African continent by ca 1.6 Ma.