Acheulean - Dating The Acheulean

Dating The Acheulean

Providing calendrical dates and ordered chronological sequences in the study of early stone tool manufacture is often accomplished through one or more geological techniques, such as radiometric dating, often potassium-argon dating, and magnetostratigraphy. From the Konso Formation of Ethiopia, Acheulean hand-axes are dated to about 1.5 million years ago using radiometric dating of deposits containing volcanic ashes. However, the earliest accepted examples of the Acheulean currently known come from the West Turkana region of Kenya and were first described by a French-led archaeology team. These particular Acheulean tools were recently dated through the method of magnetostratigraphy to about 1.76 million years ago, making them the oldest not only in Africa but the world. From geological dating of sedimentary deposits, it appears that the Acheulan originated in Africa and spread to Asian, Middle Eastern, and European areas sometime between 1.5 million years ago and about 800 thousand years ago

Presence of Acheulean tools in South Asia have also been found to be dated as far as 1.5 million years ago.

In individual regions, this dating can be considerably refined; in Europe for example, Acheulean methods did not reach the continent until around 400,000 years ago; and in smaller study areas, the date ranges can be much shorter. Numerical dates can be misleading, however, and it is common to associate examples of this early human tool industry with one or more glacial or interglacial periods or with a particular early species of human. The earliest user of Acheulean tools was Homo ergaster, who first appeared about 1.8 million years ago. Not all researchers use this formal name, and instead prefer to call these users early Homo erectus. Later forms of early humans also used Acheulean techniques and are described below.

Relative dating techniques (based on a presumption that technology progresses over time) suggest that Acheulean tools followed on from earlier, cruder tool-making methods, but there is considerable chronological overlap in early prehistoric stone-working industries, with evidence in some regions that Acheulean tool-using groups were contemporary with other, less sophisticated industries such as the Clactonian and then later with the more sophisticated Mousterian, as well. It is therefore important not to see the Acheulean as a neatly defined period or one that happened as part of a clear sequence but as one tool-making technique that flourished especially well in early prehistory. The enormous geographic spread of Acheulean techniques also makes the name unwieldy as it represents numerous regional variations on a similar theme. The term Acheulean does not represent a common culture in the modern sense, rather it is a basic method for making stone tools that was shared across much of the Old World.

The very earliest Acheulean assemblages often contain numerous Oldowan-style flakes and core forms and it is almost certain that the Acheulean developed from this older industry. These industries are known as the Developed Oldowan and are almost certainly transitional between the Oldowan and Acheulean.