Middle Stone Age to Later Stone Age Transition in Eastern Africa

Abstract The Middle Stone Age (MSA) to Later Stone Age (LSA) transition has roots in the MSA, and the latter is thus a watershed for many of the behavioral and technological transformations seen in the LSA. These include modern behavioral traits of miniaturization of artifacts in the Later Pleistocene, personal adornment, and long-distance exchange of obsidian. Population expansion in and out of Africa also occurs in the Later Pleistocene. The MSA/LSA transition not only exhibits most of the technological and behavioral traits of the MSA but also introduces microlithic technological components and increases modern behavior practices introduced in the MSA. For example, the bow and arrow can be argued to be an improvement of projectile weapons first introduced in the MSA during the Mid-Later Pleistocene. After approximately 40 ka, transition assemblages in eastern Africa lose most MSA elements, including the large Howiesons Poort–type backed microliths, and blade and microblade technologies dominate toolkits, heralding a distinct technology phase—the LSA. While unified by small backed blade–based tools, the LSA remains a complex technological phase with regional and temporal variations. Across the continent, the LSA lasts up to the end of the Last Glacial Maximum, although it persisted in some sites up to the mid-Holocene. At the end of the last glacial period (10–12 ka), some LSA foragers around Lake Turkana began to fish intensively. At approximately 5.5 ka, local forager populations in the Turkana Basin adopted domestic animals—cattle, goats, and sheep—heralding the start of a food production era in the region known as the Pastoralist Neolithic. This transition to food production by former foragers is recorded at some sites with MSA/LSA transition and LSA assemblages, reinforcing the essential role of cultural innovation in hominin adaptation.