The stone tool styles that tookHomo Sapiensout of Africa and across much of the world were gradually substitute with raw implements , and were guess to have been abandon entirely by 30,000 year ago . New discovery reveal that in West Africa this modulation was not made until long after the rest of the universe , with replacement only appearing around 11,000 class ago .
Long beforeH. Sapiens’arrival on the panorama other former human species had refined stone tool use to a okay artistry . The first bones of our own species are associated with the coming into court of a distinctive style of flaking tools , scrapers , and grinding gemstone anthropologists come to to as theMiddle Stone Age . As the name intimate , there was also a Later Stone Age , commemorate by much smaller tools andostrich eggshell beads . These first appeared around 67,000 year ago , and by 30,000 years ago were consider to have exchange the larger tools that served humanity for almost 300,000 geezerhood everywhere in Africa .
Dr Eleanor Scerriof the Max Planck Institute for the Science of Human History has challenged this notion based on sites she has examined in Senegal in particular . " West Africa is a real frontier for human evolutionary studies – we know almost nothing about what come about here in deep prehistoric culture , ” Scerri read in astatement . “ Almost everything we know about human origins is extrapolated from discoveries in small parts of eastern and southern Africa , "
Scerri partner withDr Khady Niangof Senegal ’s University of Cheikh Anta Diop to study Senegal ’s sites where mankind tarried across the land ’s various environs , which range from thick rain forest to desert fringes . InScientific Reportsthey key out abundant Middle Stone Age tools at internet site near two of the nation ’s major river . UsingOptically Stimulated Luminescence(OSL ) , which measure how long an object has been forget off from sunlight , one of these was dated at 21,000 - 24,000 years ago , the other 11,000 years old .
Scerri , Niang and Centennial State - authors observe this is consistent with their old find of a Middle Stone Age tools at another 11,600 - year - quondam Senagalese situation . Other sites across West Africa have not been as precisely dated , but they could be as young as 20,000 - 25,000 years honest-to-god .
Co - authorDr Jimbob Blinkhornattributes the tools ’ endurance to the part ’s isolation from the residue of manhood at the time . “ To the north , the area meets the Sahara Desert , " he said . " To the east , there are the cardinal African rainforest , which were often cut off from the West African rainforests during geological period of drouth and fragmentation . ”
" This matches transmitted study suggesting that African mass go in the last 10 thousand years lived in very subdivided populations , " Niang added .
Moreover , the clime of Western Africa appears to have been more stable during the last Ice Age than the residue of the continent . Without the insistence of changing conditions people living in the region may have had footling need to empty the tools that served their ancestors so well . Not until the Holocene had nearly begun did greater humidity dilate West Africa ’s forest , possibly link up them to those in Central Africa and sparking a ethnical interchange .
