The Oldowan (or Mode I) was a widespread stone tool archaeological industry (style) in prehistory. These early tools were simple, usually made with one or a few flakes chipped off with another stone. Oldowan tools were used during the Lower Paleolithic period, 2.6 million years ago up until at least 1.7 million years ago, by ancient Hominins (early humans) across much of Africa. This technological industry was followed by the more sophisticated Acheulean industry (two sites associated with Homo erectus at Gona in the Afar Region of Ethiopia dating from 1.5 and 1.26 million years ago have both Oldowan and Acheulean tools[2]). Oldowan Canto tallado 2-Guelmim-Es Semara.jpg Geographical range Afro-Eurasia Period Lower Paleolithic Dates 2.6 million years BP – 1.7 million years BP Major sites Olduvai Gorge Preceded by Lomekwi 3[1] Followed by Acheulean The term Oldowan is taken from the site of Olduvai Gorge in Tanzania, where the first Oldowan stone tools were discovered by the archaeologist Louis Leakey in the 1930s. However, some contemporary archaeologists and palaeoanthropologists prefer to use the term Mode 1 tools to designate pebble tool industries (including Oldowan), with Mode 2 designating bifacially worked tools (including Acheulean handaxes), Mode 3 designating prepared-core tools, and so forth.[3] Classification of Oldowan tools is still somewhat contentious. Mary Leakey was the first to create a system to classify Oldowan assemblages, and built her system based on prescribed use. The system included choppers, scrapers, and pounders.[4][5] However, more recent classifications of Oldowan assemblages have been made that focus primarily on manufacture due to the problematic nature of assuming use from stone artefacts. An example is Isaac et al.'s tri-modal categories of "Flaked Pieces" (cores/choppers), "Detached Pieces" (flakes and fragments), "Pounded Pieces" (cobbles utilized as hammerstones, etc.) and "Unmodified Pieces" (manuports, stones transported to sites).[6] Oldowan tools are sometimes called "pebble tools", so named because the blanks chosen for their production already resemble, in pebble form, the final product.[7] It is not known for sure which hominin species created and used Oldowan tools. Its emergence is often associated with the species Australopithecus garhi[8] 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.[9] Dates and ranges Edit The oldest known Oldowan tools have been found in Gona, Ethiopia (near the Awash River), and are dated to about 2.6 mya.[10] The use of tools by apes including chimpanzees[11] and orangutans[12] can be used to argue in favour of tool-use as an ancestral feature of the hominin family.[13] Tools made from bone, wood, or other organic materials were therefore in all probability used before the Oldowan.[14] Oldowan stone tools are simply the oldest recognisable tools which have been preserved in the archaeological record. There is a flourishing of Oldowan tools in eastern Africa, spreading to southern Africa, between 2.4 and 1.7 mya. At 1.7 mya., the first Acheulean tools appear even as Oldowan assemblages continue to be produced. Both technologies are occasionally found in the same areas, dating to the same time periods. This realisation required a rethinking of old cultural sequences in which the more "advanced" Acheulean was supposed to have succeeded the Oldowan. The different traditions may have been used by different species of hominins living in the same area, or multiple techniques may have been used by an individual species in response to different circumstances. Sometime before 1.8 mya Homo erectus had spread outside of Africa, reaching as far east as Java by 1.8 mya[15] and in Northern China by 1.66 mya.[16] In these newly colonised areas, no Acheulean assemblages have been found. In China, only "Mode 1" Oldowan assemblages were produced, while in Indonesia stone tools from this age are unknown. By 1.8 mya early Homo was present in Europe, as shown by the discovery of fossil remains and Oldowan tools in Dmanisi, Georgia.[17] Remains of their activities have also been excavated in Spain at sites in the Guadix-Baza basin[18] and near Atapuerca.[19] Most early European sites 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.[20] It is unclear from the archaeological record when the production of Oldowan technologies ended. Other tool-making traditions seem to have supplanted Oldowan technologies by 0.25 mya. The discovery of stone tools that predate the Oldowan, dated to as early as 3.3 mya (million years ago), at the Lomekwi site in Kenya, was announced in 2015.[21] This age pre-dates the current estimates for the age of the genus Homo by half a million years, and would fall into the pre-human period, associated with the direct australopithecine ancestors of genus Homo. It is not clear whether the tools of such a "Lomekwian industry" bear any relation to the Oldowan industry.[22] Tools Edit Learn more This section does not cite any sources. (December 2019) Manufacture Edit 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 have helped spark careful studies of Oldowan techniques. These techniques have now been duplicated many times by archaeologists and other knappers, making misidentification of archaeological finds less likely. Use of bone tools by hominins also producing Oldowan tools is known from Swartkrans, where a bone shaft with a polished point was discovered in Member (layer) I, dated 1.8–1.5 mya. The Osteodontokeratic industry, the "bone-tooth-horn" industry hypothesized by Raymond Dart, is less certain. Shapes and uses Edit Oldowan-tradition stone chopper. Mary Leakey classified the Oldowan tools as Heavy Duty, Light Duty, Utilized Pieces and Debitage, or waste.[23] 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 as axes for woodworking. 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 pointed tools. Such uses are attested by characteristic microscopic alterations of edges used to scrape wood. Oldowan tools could also have been used for preparing hides. Hides must be cut by slicing, piercing and scraping them clean of residues. Flakes are most suitable for this purpose. 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 Edit 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 and promoted the African origin of man. Oldowan soon replaced Abbevillian in describing African and Asian lithics. The term Abbevillian is still used but 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. Because Abbevillian did not necessarily precede Acheulean and both traditions had flakes and bifaces, it became difficult to differentiate the two. It was in this spirit that many artifacts formerly considered Abbevillian were labeled Acheulean. In consideration of the difficulty, some preferred to name both phases Acheulean. When the topic of Abbevillian came up, it was simply put down as a phase of Acheulean. Whatever was from Africa was Oldowan, and whatever from Europe, Acheulean. The solution to the definition problem is stated in the article on Acheulean. The difference is to be defined in terms of complexity. Simply struck tools are Oldowan. Retouched, or reworked tools are Acheulean. 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 Acheulean, but this is the now false Acheulean, 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. Tool users Edit Learn more This section needs additional citations for verification. (January 2010) 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 genera Australopithecus and Homo. There is also evidence that some species of Paranthropus utilized stone tools.[24] There is presently no evidence to show that Oldowan tools were the sole creation of members of the Homo line or that the ability to produce them was a special characteristic of only our ancestors. Research on tool use by modern wild chimpanzees in West Africa shows there is an operational sequence when chimpanzees use lithic implements to crack nuts. In the course of nut cracking, sometimes they will create unintentional flakes. Although the morphology of the chimpanzees' hammer is different from the Oldowan hammer, chimpanzees' ability to use stone tools indicates that the earliest lithic industries were probably not produced by only one kind of hominin species.[25] The makers of Oldowan tools were mainly right-handed.[26] "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.[clarification needed] In the mid-1970s, Glynn Isaac touched off a debate by proposing that human ancestors of this period had a "place of origin" and that they foraged outward from this home base, 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 strategy. 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 and Lewis Binford) 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. 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 hominins hunted smaller animals, but were not above driving carnivores from larger kills, as they probably were driven from kills themselves from time to time. Sites and archaeologists Edit A complete catalog of Oldowan sites would be too extensive for listing here. Some of the better-known sites include the following: