Middle Stone Age
This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Anthropology. Please check back later for the full article. The Middle Stone Age (MSA) is a period of African prehistory characterized by the production of stone points and blades using prepared core reduction techniques. The MSA follows the Earlier Stone Age and precedes the Later Stone Age. The MSA is generally regarded as having started by at least 300 thousand years ago, and lasting to roughly 40 to 20 thousand years ago. Identifying the chronological limits for the MSA is challenging because some aspects of Middle Stone Age technology are found in assemblages outside this time range that also have Earlier or Later Stone Age-type tools. The earlier part of the MSA is associated with Homo heidelbergensis (alternatively known as archaic Homo sapiens, or Homo rhodesiensis). The later part of the MSA, post-200-thousand-years, ago is associated with Homo sapiens. Identifying the processes underlying the evolution of Homo sapiens during the MSA is a major objective of ongoing research, but very few fossil remains have been recovered so far. Across the African continent and through time, the MSA exhibited a high degree of variability in the types of and ways that stone tools were manufactured and used. Archaeologists have used this variability to define several techno-complexes and industries within the MSA that include the Aterian, Howiesons Poort, Still Bay, and Lupemban. Variation in point styles, presumably hafted to wooden handles or projectiles in many cases, is a hallmark of the regional diversification that originates in the MSA. This kind of variability, which is temporally and spatially restricted, differs in degree from the preceding Earlier Stone Age. The MSA is significant from an evolutionary perspective because it is associated with the anatomical origins of Homo sapiens, as well as several significant changes in human behavior. Populations in the MSA practiced a foraging economy, were proficient hunters, and began efficiently utilizing aquatic resources such as shellfish and freshwater fish for the first time. Other significant changes included the elaboration of and increased reliance on symbolic resources, complex technologies, and social learning. For example, the first known externally stored symbols in the form of cross-hatched incised pigments date to 100 thousand years ago. In contexts of similar age, shell beads for making jewelry have been recovered from Morocco and South Africa. The earliest evidence for complex projectiles dates to at least 74 thousand years ago. The meaning, utility, and persistence of symbols and complex technologies depend on social learning and confer advantages in contexts that involve long-distance, complex social networks. While many of these earliest finds linked to behavioral modernity have been geographically restricted, the combined suite of genetic, fossil, and archaeological evidence may better support a pan-African origin for Homo sapiens over the course of the MSA.