The Middle to Later Stone Age technological transition in East Africa. New data from Mumba Rockshelter Bed V (Tanzania) and their implications for the origin of modern human behavior

Abstract

Recent re-excavation of Mumba Rockshelter unearthed an unbiased lithic sample from Bed V. Technological analysis has permitted a reinterpretation of the so-called Mumba Industry, a transitional industry between Middle and Later Stone Ages originally defined by Mehlman (1989). Our data confirm Mehlman’s observation that the “evolutionary” markers in Mumba Bed V are basically typological. However, our study differs from his in that we classify all of Bed V as LSA based on the combined analyses of typology and technology in our excavated assemblage. From a technological perspective, no changes have been observed throughout the sequence, and continuity is the main technological characteristic of the series. The only transitional marker from Lower through Upper Bed V is the appearance of the geometric crescent in the latter, taking into account that microliths exist throughout the sequence. This evidence casts some doubts on previous interpretations and underscores the need to recover a larger sample using modern excavation techniques. It also stresses the need to define the MSA/LSA transition in better terms, combining techno-typological criteria.