Oldowan - The Tool Users

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.