<Dd> final MSA phases </Dd> <Tr> <Td> ↓ Later Stone Age </Td> </Tr> <P> The Middle Stone Age (or MSA) was a period of African prehistory between the Early Stone Age and the Later Stone Age . It is generally considered to have begun around 280,000 years ago and ended around 50--25,000 years ago . The beginnings of particular MSA stone tools have their origins as far back as 550--500,000 years ago and as such some researchers consider this to be the beginnings of the MSA . The MSA is often mistakenly understood to be synonymous with the Middle Paleolithic of Europe, especially due to their roughly contemporaneous time span, however, the Middle Paleolithic of Europe represents an entirely different hominin population, Homo neanderthalensis, than the MSA of Africa, which did not have Neanderthal populations . Additionally, current archaeological research in Africa has yielded much evidence to suggest that modern human behavior and cognition was beginning to develop much earlier in Africa during the MSA than it was in Europe during the Middle Paleolithic . The MSA is associated with both anatomically modern humans (Homo sapiens) as well as archaic Homo sapiens, sometimes referred to as Homo helmei . Early physical evidence comes from the Gademotta Formation in Ethiopia, the Kapthurin Formation in Kenya and Kathu Pan in South Africa . </P> <P> It is difficult to discuss the MSA of Africa without first considering the immense size of the continent . There are archaeological sites and evidence from across the continent, and, for the sake of ease, it has often been divided into five regions: northern Africa, which is often, though not without controversy, taken into consideration more so with Southwest Asia and Europe than with the rest of Africa; eastern Africa, stretching roughly from the highlands of Ethiopia to the southern part of Kenya; central Africa, which is arguably the least explored region, stretching from the borders of Tanzania and Kenya to include Angola; southern Africa, which includes the numerous cave sites of South Africa; and western Africa . </P>

When did the middle stone age begin and end
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