<P> These facts show that there were sufficient resources and co-operation to enable large groups to work on these projects . To what extent this was a basis for the development of elites and social hierarchies is a matter of ongoing debate . Although some late Neolithic societies formed complex stratified chiefdoms similar to Polynesian societies such as the Ancient Hawaiians, based on the societies of modern tribesmen at an equivalent technological level, most Neolithic societies were relatively simple and egalitarian . A comparison of art in the two ages leads some theorists to conclude that Neolithic cultures were noticeably more hierarchical than the Paleolithic cultures that preceded them . </P> <P> This period is not to be identified with "Old Stone Age", a translation of Paleolithic, or with Paleolithic, or with the "Earlier Stone Age" that originally meant what became the Paleolithic and Mesolithic . In the initial decades of its definition by the Pan-African Congress of Prehistory, it was parallel in Africa to the Upper and Middle Paleolithic . However, since then Radiocarbon dating has shown that the Middle Stone Age is in fact contemporaneous with the Middle Paleolithic . The Early Stone Age therefore is contemporaneous with the Lower Paleolithic and happens to include the same main technologies, Oldowan and Acheulean, which produced Mode 1 and Mode 2 stone tools respectively . A distinct regional term is warranted, however, by the location and chronology of the sites and the exact typology . </P> <P> The Middle Stone Age was a period of African prehistory between Early Stone Age and Late Stone Age . It began around 300,000 years ago and ended around 50,000 years ago . It is considered as an equivalent of European Middle Paleolithic . It is associated with anatomically modern or almost modern Homo sapiens . Early physical evidence comes from Omo and Herto, both in Ethiopia and dated respectively at c. 195 ka and at c. 160 ka . </P> <P> The Later Stone Age (LSA, sometimes also called the Late Stone Age) refers to a period in African prehistory . Its beginnings are roughly contemporaneous with the European Upper Paleolithic . It lasts until historical times and this includes cultures corresponding to Mesolithic and Neolithic in other regions . </P>

What are the four periods of the stone age