The Isimila stone age project

Funded by the Society of Antiquaries and Quaternary Research Association, The Isimila Stone Age Project was an international research collaboration led by Dr James Cole (University of Brighton) and Co-investigated by Dr John McNabb (University of Southampton), Dr Martin Bates (University of Wales Trinity St David) and Dr Pastory Bushozi (University of Dar es Salaam).

The project was formed in order to revisit the famous Stone Age site of Isimila located on the Iringa plateau, Tanzania, close to the East African Rift Valley with a modern research focus and methodology.

East Africa has long been associated with the origins of a number of hominin species, including our own genus Homo c. 2.3mya, and a material culture record now stretching back almost 3.3 million years. What is not so well known or documented is the Palaeolithic archaeology or behavioural record of hominins located outside the Rift Valley. One major Stone Age site, called Isimila, is located within a korongo (erosion gulley) on the Iringa plateau in Tanzania and has long been recognised as a site of international importance for understanding the behavioural complexity and plasticity of our hominin ancestors.

One of the primary reasons for the importance of Isimila is the unique artefact record for a site outside the Rift Valley system present in both primary and secondary contexts consisting of thousands of handaxes - including enigmatic giant handaxes. Despite the international significance of Isimila, the archaeology, chronology, taphonomy and geomorphology of the site remain poorly understood, and in urgent need of re-examination.

In order to try and resolve the issues of chronology at Isimila, the project team collected 16 sediment samples through the range of stratigraphic contexts present at the site. The purpose of collecting the sediment samples was to enable a series of dating analyses through techniques such as Optically Stimulated Luminescence (OSL) and post-IR infrared stimulated luminescence (pIRIR-SL). These analyses are still being processed and we will update these pages once we have the results.

In addition to trying to resolve the chronological questions surrounding Isimila, the project team also undertook a small raw material analysis study led by Dr John McNabb and funded through a small grant from the Society of Antiquaries, (London). The purpose of this study was to analyse the lithologies of raw material outcrops within a 5km radius of Isimila against a sample of Isimila handaxes using Portable X-Ray Florescence (PXRF). The aim was to identify potential raw material sources that may have been exploited by past hominins in the Isimila landscape. This in turn would shed light on past hominin raw material exploitation strategies, planning depth and the range of hominin movements.