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The Oldowan, often spelled Olduwan or Oldawan, is the archaeological term used to refer to the stone tool industry that was used by Hominines during the Lower Paleolithic period. The Oldowan is significant for being the earliest stone tool industry in prehistory, being used from 2.6 million years ago up until 1.7 million years ago, when it was followed by the more sophisticated Acheulean industry. Oldowan tools were therefore the earliest tools in human history, and mark the beginning of the archaeological record. The term "Oldowan" is taken from the site of Olduvai Gorge in Tanzania, where the first Oldowan tools were discovered by the archaeologist Louis Leakey in the 1930s. However, some contemporary archaeologists and palaeoanthropologists prefer to use the term "Mode One" tools to designate Oldowan tools, with "Mode Two" designated Acheulean ones and so forth.
It is not known for sure which hominin species actually created and used Oldowan tools. Its emergence is often associated with the species Australopithecus garhi, and its flourishing with early species of Homo such as H. habilis and H. ergaster. Early Homo erectus appears to inherit Oldowan technology and refines it into the Acheulean industry beginning 1.7 million years ago. Oldowan tools are sometimes called "pebble tools," so named because the blanks chosen for their production already resemble, in pebble form, the final product. Oldowan tools are sometimes subdivided into types, such as chopper, scrapers and pounders, as these appear to have been their main uses.
- 1 Dates and ranges
- 2 Sites and archaeologists
- 2.1 East Africa
- 2.2 South Africa
- 2.3 Asia
- 2.4 Europe
- 3 The tools
- 4 The tool users
- 5 Notes
- 6 Sources
- 7 External links
Dates and ranges
These tools should not be regarded as evidence of the first use of tools. The use of tools in apes, like chimpanzees and orangutans can be used to argue in favour of tool-use as an ancestral feature of the hominin family. Tools were therefore in all probability used before the Oldowan. Oldowan stone tools are simply the oldest recognisable tools which have been preserved in the archaeological record, presumably manufactured by species in the hominin family.
There is a flourishing of Oldowan tools in East Africa, spreading to South Africa, between 2.4 and 1.7 mya. At 1.7 mya., the first Acheulean appears. However, Oldowan assemblages continue to be produced. The two techniques were also used in the same areas. This realisation required a rethinking of old cultural sequences in which the more "advanced" Acheulean was supposed to succeed the Oldowan. A number of different interpretations of this fact have been proposed. It is thought that the different traditions may have been used by different species of hominins. On the other hand, it could be that both techniques were used by the same species in response to different circumstances.
Sometime before 1.7 mya. Homo erectus had spread outside of Africa. It has been found as far east as Java by 1.8 mya. and in Northern China by 1.66 mya. In these newly colonised areas, no Acheulean assemblages have been found. In China, only 'Mode 1" assemblages were produced, while in Indonesia stone tools from this age are unknown.
Some time before 1 mya Homo erectus, or its descendants entered Europe. Remains of their activities have been excavated mainly in Spain at sites in the Guadix-Baza basin and near Atapuerca. The earliest European sites all yield "mode 1" or Oldowan assemblages. The earliest Acheulean sites in Europe only appear around 0.5 mya. In addition, the Acheulean tradition does not seem to spread to Eastern Asia. When the technology stopped being used is unclear. Discounting modern reproductions it is probably safe to say it was mostly replaced by other toolmaking traditions by 0.25 mya.
Sites and archaeologists
A complete catalog of Oldowan tool sites would be too extensive for listing here. Hominid populations were sparse at any given time, but the span of time over which these species lived is immense.
The tools are found in many habitable sites: terraces or banks of rivers and lakes or pools, caves, or just lying around in large quantities on open ground.
Some of the better-known sites are as follows.
The type site
The Oldowan industry is named after discoveries made in the Olduvai Gorge of Tanzania in east Africa by the Leakey family, primarily Mary Leakey, but also her husband Louis and their son, Richard. Similar tools had already been found in various locations in Europe and Asia for some time, where they were called Chellean and Abbevillian.
The oldest tool sites are in the East African Rift system, on the sediments of ancient streams and lakes. This is consistent with what we surmise of the evolution of man. Genetic studies tell us that the human line possibly diverged from the chimpanzee line, and the native territory of the latter is the forests of Central Africa nearby. Fossil chimpanzees have been found in Kenya.
The forests of central and west Africa are a stable environment containing food in abundance for animals such as chimpanzees, and any species living in such an environment would have been under little pressure to evolve further. East Africa is a land of often harsh and unstable environments, and resources are correspondingly scarcer and more difficult to get. Species living in the latter environment would be under greater pressure to evolve and change as needed to survive. A facility for tool-using would contribute to the species chances of survival.
Sites in the Gona river system in the Hadar region of the Afar triangle, excavated by Helene Roche, J. W. Harris and Sileshi Semaw, yielded the oldest known Oldowan assemblages, dating to about 2.6 million years ago. Recent excavations have yielded tools in association with cut-marked bones, indicating that Oldowan were used in meat-processing or -acquiring activities.
Omo River basin
The second oldest known Oldowan tool site comes from the Shungura formation of the Omo River basin. This formation documents the sediments of the Plio-Pleistocene and provides a record of the hominins that lived there. Oldowan begins in levels E and F at 2.4–2.3 million years ago.
The tools are never found in direct association with the hominins, but archaeologists believe that they would be the strongest candidates for tool manufacture. There are no hominins in those layers, but the same layers elsewhere in the Omo valley contain Paranthropus and early Homo fossils. Paranthropus occurs in the preceding layers. In the last layer at 1.4 million years ago is only Homo erectus.
The numerous Koobi Fora sites on the east side of Lake Turkana are now part of Sibiloi National Park. Many scientists of various disciplines have participated in research there, but the initial sites were excavated by Richard Leakey and his wife, Meave, Jack Harris, Glynn Isaac and a few others. Currently the artifacts are classified as Oldowan or KBS Oldowan, dated from 1.9–1.7 mya, Karari (or advanced Oldowan), dated to 1.6–1.4 mya, and some early Acheulean at the end of the Karari. Over 200 hominins have been found, including Australopithecus and Homo.
Even though Olduvai Gorge is the type site, Oldowan tools from here are not the oldest known examples. They occur in Beds I–IV. Bed I, dated 1.85 mya to 1.7 mya, contains Oldowan and fossils of Paranthropus boisei as well as Homo habilis, as does Bed II, 1.7–1.2 mya. H. habilis gives way to Homo erectus at about 1.6 mya but P. boisei goes on. Oldowan continues to Bed IV at 800,000 to 600,000 before present (BP).
The Swartkrans site is a cave filled with layered fossil-bearing limestone deposits. Oldowan is found in Members (layers) I–III, 1.8–.5 mya, in association with Paranthropus robustus and Homo habilis. The Member I assemblage also includes a shaft of pointed bone polished at the pointed end.
Member I contained a high percentage of primate remains compared to other animal remains, which did not fit the hypothesis that H. habilis or P. robustus lived in the cave. C. K. Brain conducted a more detailed study and discovered the cave had been the abode of leopards, who preyed on the hominins.
Another site of limestone caves is Sterkfontein, not far from Swartkrans. Member (layer) 5 there, dating from 2 mya to 1.5 mya, contains fossils of Homo habilis as well as Oldowan tools.
Tools have been found dating from 1.9 mya.
Tools have been found dating from the Late Pliocene or Early Pleistocene.
el 'Ubeidiya, Israel
Tools have been found dating from 1.4 mya.
At the Swanscombe, Clacton on Sea open air site on the Thames discovered by Wymer and Wymer, Clactonian tools have been found.
Oldowan tools have been found at the Monte Poggiolo open air site discovered by Antoniazzi.
Tools have been found in ancient lake deposits at Przeletice and a cave site at Stranska Skala, dated no later than .5 mya.
Tools have been found at a spring site at Vértesszőlős dating from .5 mya.
Tools have been found in river gravels at Kärlich dating from .3 mya.
Oldowan tools have been found at:
Oldowan tools have been found at the following sites:
- Fuente Nueva 3
- Barranco del Leon
- Sima del Elefante
- Atapuerca TD 6
Manufacture of the tools
To obtain an Oldowan tool, a roughly spherical hammerstone is struck on the edge, or striking platform, of a suitable core rock to produce a conchoidal fracture with sharp edges useful for various purposes. The process is often called lithic reduction. The chip removed by the blow is the flake. Below the point of impact on the core is a characteristic bulb with fine fissures on the fracture surface. The flake evidences ripple marks.
The materials of the tools were for the most part quartz, quartzite, basalt, or obsidian, and later flint and chert. Any rock that can hold an edge will do. The main source of these rocks is river cobbles, which provide both hammer stones and striking platforms. The earliest tools were simply split cobbles. It is not always clear which is the flake. Later tool-makers clearly identified and reworked flakes. Complaints that artifacts could not be distinguished from naturally fractured stone helped spark a careful study of the technique. It has been duplicated many times by moderns, making misidentification less likely. Unfortunately, clandestine studies had already been undertaken by persons intent on fraud, such as the British swindler, Edward Simpson, or "Flint Jack."
Use of the point is also known from Swartkrans, as a bone shaft with a polished point was discovered there in Member (layer) I, dated 1.8–1.5 mya. The Osteodontokeratic industry hypothesized by Raymond Dart is less certain.
The tools are often referred to as "crude", although this is naturally somewhat subjective. The words "simple" or "complex" can be used with more objectivity, as there is a gradual but clear tendency toward increasing complexity. At the end of the Stone Age, the stone tools were of a high enough quality that they were imitated in metal.
Shapes and uses of the tools
Mary Leakey classified the Oldowan tools as Heavy Duty, Light Duty, Utilized Pieces and Debitage, or waste. Heavy-duty tools are mainly cores. A chopper has an edge on one side. It is unifacial if the edge was created by flaking on one face of the core, or bifacial if on two. Discoid tools are roughly circular with a peripheral edge. Polyhedral tools are edged in the shape of a polyhedron. In addition there are spheroidal hammer stones.
Light-duty tools are mainly flakes. There are scrapers, awls (with points for boring) and burins (with points for engraving). Some of these functions belong also to heavy-duty tools. For example, there are heavy-duty scrapers.
Utilized pieces are tools that began with one purpose in mind but were utilized opportunistically.
Oldowan tools were probably used for many purposes, which have been discovered from observation of modern apes and hunter-gatherers. Nuts and bones are cracked by hitting them with hammer stones on a stone used as an anvil. Battered and pitted stones testify to this possible use.
Heavy-duty tools could be used for woodworking, in the function of an axe. Both choppers and large flakes were probably used for this purpose. Once a branch was separated, it could be scraped clean with a scraper, or hollowed with the pointed tools. Such uses are attested by characteristic microscopic alterations of edges used to scrape wood.
If stone tools were valuable for working wood, they were invaluable for preparing hide. The hide must be cut by slicing, pierced and scraped clean of residues. Hides could be used for clothing, shelters or containers. The rest of the animal also had to be butchered, for ease of consuming, and probably convenience in carrying and perhaps distributing the meat. Flakes are most suitable for this purpose.
In addition, pointed bones or sticks were probably used for digging for roots and tubers. Wood branches were probably used for missiles and clubs. Branches were woven into shelters or sleeping nests.
Hypotheses on Oldowan tool use have gone past the point of mere guesswork. Lawrence Keeley, following in the footsteps of Sergei Semenov, conducted microscopic studies (with a high-powered optical microscope) on the edges of tools manufactured de novo and used for the originally speculative purposes described above. He found that the marks were characteristic of the use and matched marks on prehistoric tools. Studies of the cut marks on bones using an electron microscope produce a similar result.
Abbevillian is a currently obsolescent name for a tool tradition that is increasingly coming to be called Oldowan. The label Abbevillian prevailed until the Leakey family discovered older (yet similar) artifacts at Olduvai Gorge (a.k.a Oldupai Gorge) and promoted the African origin of man. Olduwan (or Oldowan) soon replaced Abbevillian in describing African and Asian paleoliths. The term Abbevillian is still used, but it is now restricted to Europe. The label, however, continues to lose popularity as a scientific designation.
In the late 20th century, discovery of the discrepancies in date caused a crisis of definition. If Abbevillian did not necessarily precede Acheulian and both traditions had flakes and bifaces, how was the difference to be defined? It was in this spirit that many artifacts formerly considered Abbevillian were labeled Acheulian. In consideration of the difficulty, some preferred to name both phases Acheulian. When the topic of Abbevillian came up, it was simply put down as a phase of Acheulian. Whatever was from Africa was Oldowan, and whatever from Europe, Acheulian.
The solution to the definition problem is stated in the article on Acheulian. The difference is to be defined in terms of complexity. Simply struck tools are Oldowan. Retouched, or reworked tools are Acheulian. Retouching is a second working of the artifact. The manufacturer first creates an Oldowan tool. Then he reworks or retouches the edges by removing very small chips so as to straighten and sharpen the edge. Typically but not necessarily the reworking is accomplished by pressure flaking.
The pictures in the introduction to this article are mainly labeled Acheulian, but this is the now false Acheulian, which also includes Abbevillian. The artifacts shown are clearly in the Oldowan tradition. One or two of the more complex bifaces may have edges made straighter by a large percussion or two, but there is no sign of pressure flaking as depicted. The pictures included with this subsection show the difference.
The tool users
Current anthropological thinking is that Oldowan tools were made by late Australopithecus and early Homo. Homo habilis was named "skillful" because it was considered the earliest tool-using human ancestor. Indeed, the genus Homo was in origin intended to separate tool-using species from their tool-less predecessors, hence the name of Australopithecus garhi, garhi meaning "surprise", a tool-using Australopithecine discovered in 1996 and described as the "missing link" between the Australopithecus and Homo genera. There is also evidence that some species of Paranthropus utilized the tools associated with this culture.
There is presently no evidence to show that Oldowan tools were the sole property of the Homo line or that the ability to produce them was the special characteristic of only our ancestors.
The makers of Oldowan tools were mainly right-handed. "Handedness" (lateralization) had thus already evolved, though it is not clear how related to modern lateralization it was, since other animals show handedness as well.
In the early 1970s, Glynn Isaac touched off a debate by proposing that hominids of this period had a "place of origin" and that they foraged outward from this, returning with high quality food to share and to be processed. Over the course of the last 30 years, a variety of competing theories about how foraging occurred have been proposed, each one implying certain kinds of social strategies. The available evidence from the distribution of tools and remains is not enough to decide which theories are the most probable. However, three main groups of theories predominate.
- Glynn Isaac's model became the Central Forage Point - as he responded to critics that accused him of attributing too much 'modern' behavior to early Hominins with relatively free-form searches outward.
- A second group of models took modern chimpanzee behavior as a starting point, having the hominids use relatively fixed routes of foraging, and leaving tools where it was best to do so on a constant track.
- A third group of theories had relatively loose bands scouring the range, taking care to move carcasses from dangerous death sites and leaving tools more or less at random.
Each group of models implies different grouping and social strategies, from the relative altruism of central base models to the relatively disjointed search models. (See also central foraging theory, scavenging station model, Lewis Binford)
Most models rely on social and communication networks to hold the band together. These social networks range from requiring no more communication than modern primates, to requiring more sophisticated sharing and teaching. At present, no evidence has been found that sharply divides these theories.
Hominins probably lived in social groups that had contact with others. This conclusion is supported by the large number of bones at many sites, too large to be the work of one individual, and all of the scatter patterns implying many different individuals. Since modern primates in Africa have fluid boundaries between groups, as individuals enter, become the focus of bands, and others leave, it is also probable that the tools we find are the result of many overlapping groups working the same territories, and perhaps competing over them. Because of the huge expanse of time and the multiplicity of species associated with possible Oldowan tools, it is difficult to be more precise than this, since it is almost certain that different social groupings were used at different times and in different places.
As the Olduwan period moved forward, it is probable that the home base form became more prevalent and eventually dominant. Heat-blackened artifacts and baked clay at the 20 east site of Koobi Fora, and fire-blackened bones at Swartkrans, both from 1.5 mya, indicate the possible presence of the camp fire, though it is still not clear how well developed was usage of fire at this time. A circle of stones at site DK in Bed I at Olduvai indicates a possible shelter. By 750K, patches of fire use are found outside of Africa. Fire creates a more powerful center of gravity, as does the continuous inhabitation of caves and other forms of natural shelter.
There is also the question of what mix of hunting, gathering and scavenging the tool users employed. Early models focused on the tool users as hunters. The animals butchered by the tools include waterbuck, hartebeest, Springbok, pig and zebra. However, the disposition of the bones allows some question about hominin methods of obtaining meat. That they were omnivores is unquestioned, as the digging implement and the probable use of hammer stones to smash nuts indicate. Lewis Binford first noticed that the bones at Olduvai contained a disproportionately high incidence of extremities, which are low in food substance. He concluded other predators had taken the best meat, and the hominins had only scavenged. The counter view is that while hunting many large animals would be beyond the reach of an individual human, groups could bring down larger game, as pack hunting animals are capable of doing. Moreover, since many animals both hunt and scavenge, it is possible that hominis hunted smaller animals, but were not above driving carnivores from larger kills, as they probably were driven from kills themselves from time to time.
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- ^ Many scientists had drawn the erroneous conclusion that Homo habilis was the predator responsible for these remains, using Olduwan tools. The higher percentage of primate bones was interpreted as a kind of cannibalism, feeding the imagination of Raymond Dart. Brain examined the bones and concluded that the marks resulting from stripping and chewing the bones were made by a leopard.
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- Oldowan Pebble Handaxes of Europe
- Oldowan Flake Tool
- Stone Age Hand-axes
- Early Palaeolithic
- STONE AGE REFERENCE COLLECTION
- Microwear polishes on early stone tools from Koobi Fora, Kenya, article in Nature 293, 464–465 (8 October 1981). The summary and the references are displayed at no charge at the Nature site.
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- Lower Paleolithic
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