Were environmental or demographic factors the driving force behind Middle Stone Age innovations in southern Africa?

Abstract

Past human responses to environmental changes have long interested archaeologists. During the last glacial cycle, southern Africa experienced marked climatic fluctuations, as recorded in ice-core records from West and East Antarctica. Two phases of technological and behavioural innovation, known as the Still Bay (SB) and Howieson's Poort (HP) industries, also occurred during this interval of the Middle Stone Age (MSA). Recently, we reported improved estimates for the start and end dates, and durations, of these two industries, and argued that the SB and HP did not reflect a response to environmental factors alone.