July 31, 2012
Later Stone Age In South Africa Emerged Earlier Than Previously Believed
April Flowers for redOrbit.com - Your Universe Online
Two recent articles in Proceedings of the National Academy of Sciences show that the Later Stone Age (LSA) and Modern Culture both emerged much earlier than was previously thought.
A team of international scientists from South Africa, France, Italy, Norway, the USA and Britain dated and directly analyzed organic objects found in the archaeological layers at Border Cave, South Africa in the Lebombo Mountains near the border of Swaziland.
The team carbon-dated many organic objects, including beads made from ostrich eggshells, thin bone arrowhead points, wooden digging sticks, a gummy substance called pitch and a lump of beeswax. The last two objects were both used to haft bone or stone blades to shafts. Also found were worked tusks used for planing wood and notched bones used for counting.
The first article, "Border Cave and the Beginning of the Later Stone Age in South Africa," shows that the onset of the LSA emerged in Africa more than 20,000 years earlier than researchers had previously believed. The Later Stone Age in South Africa, also referred to as the Upper Paleolithic Period in Europe, is when modern humans moved from Africa to Europe between 44,000 and 42,000 years ago, signaling the end of the Neanderthals.
"Our research proves that the Later Stone Age emerged in South Africa far earlier than has been believed and occurred at about the same time as the arrival of modern humans in Europe," said Paola Villa, a curator at the University of Colorado Museum of Natural History and lead study author. "But differences in technology and culture between the two areas are very strong, showing the people of the two regions chose very different paths to the evolution of technology and society."
Of particular interest in this study were the wooden digging stick and a lump of beeswax wrapped in plant fibers, both of which dated to about 40,000 years ago. The age of these objects make them the oldest artifacts of their kind known from Africa. The digging stick and associated stone weights are very similar to digging implements used by the women of the prehistoric San people of this region used to unearth bulbs and termite larvae. The beeswax, used to haft, or attach, points for arrows to the wooden shafts, is the oldest known beeswax used by humans ever discovered. Another first for this study was the use of pitch. A 2011 study by Villa and Wil Roebroeks of Leiden University in the Netherlands showed that while European Neanderthals mastered the use of pitch 200,000 years ago, the pitch found in Border Cave is the "first time pitch-making is demonstrated in South Africa," said Villa.
The team also studied thin bone points which indicated that the shift in hunting technology from stone tipped spears of the Middle Stone Age to the bows and poison tipped arrows of the Late Stone Age was occurring at this same time. The poison was most likely derived from castor oil plants and was necessary for successful kills with these early projectile weapons.
The second article to come from this research team, "Early evidence of San material culture represented by organic artifacts from Border Cave, South Africa" led by Francesco d'Errico, Director of Research at the French National Research Centre, used these same organic objects to answer a key question in human evolution. When in prehistory did human cultures similar to our own emerge?
Before this study, researchers believed that the oldest traces of San hunter-gatherer culture in Africa dated back at most 20,000 years.
"The dating and analysis of archaeological material discovered at Border Cave in South Africa, has allowed us to demonstrate that many elements of material culture that characterize the lifestyle of San hunter-gatherers in southern Africa, were part of the culture and technology of the inhabitants of this site 44,000 years ago," says Dr. Lucinda Blackwell. Blackwell is a senior researcher in paleoanthropology at the Bernard Price Institute for Paleontological Research at Wits University in Johannesburg, South Africa.
Blackwell asserts that the dating of the wooden digging stick demonstrates inarguably that the people at Border Cave were using tools traditional to the San culture.
"They adorned themselves with ostrich egg and marine shell beads, and notched bones for notational purposes. They fashioned fine bone points for use as awls and poisoned arrowheads. One point is decorated with a spiral groove filled with red ochre, which closely parallels similar marks that San make to identify their arrowheads when hunting," says Blackwell.
According to Blackwell, the objects were easy to name and identify because they all have specific reasons and uses that we, as modern people, can understand: weapons, jewelry and tools.
Professor d'Errico states that these objects tell the story of a highly evolved people. “They were fully modern genetically and cognitively,” d´Errico said.
Stone tools found in the same archeological layers as the organic objects, and from even earlier deposits, show an evolution in tool use that was gradual. The organic artifacts, however, which are inescapably reminiscent of San culture, appear relatively abruptly. This highlights an apparent mismatch in rates of cultural change, supporting the theory that what we perceive today as "modern behavior" is the result of non-linear trajectories. These might be better understood when documented on a regional scale, rather than a global one.
One claim made by this article is already in contention despite just being published July 30, 2012. The team claims that the fossils show that all modern culture emerged from southern Africa. Eric Delson, from Lehman College of the City University of New York agrees that while the testing used to date the objects is very clear and reliable, the findings do not support the stance that all modern cultures are connected to this find. Evidence of existing modern cultures in Europe that date from approximately the same rough time give a little more credence to the idea of non-linear development of culture.
“They say, ℠Modern human behavior first found!´” Delson said. “Well, not exactly.”