Stone tools, burnt eggshells, and other artifacts discovered in the Kalahari make experts question the long-held belief that civilization emerged from coastal regions.
The items date from more than 100,000 years ago when the South African desert received enough rain to feed the human inhabitants.
The researchers also found nearly two dozen tiny pieces of calcite believed to be the oldest known crystals used by humans – suggesting that the spiritual ritual was part of humanity for a long time.
They were able to date their results using luminescence dating, which measures the amount of sunlight that has accumulated in minerals over millennia.
Because the objects with the oldest artifacts from coastal locations in southern Africa are contemporary, experts say the early people of the Kalahari were just as innovative as their seaside neighbors.
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Shards of calcite crystal likely used in rituals were among the artifacts found at the Ga-Mohana Hill North Rockshelter in the southern Kalahari
Video courtesy of Griffith University
An international team of researchers located the objects in a rock shelter on Ga Mohana Hill, which is located over a vast savannah in the southern Kalahari Basin.
Their excavation revealed hundreds of stone tools, as well as animal bones with signs of butchery and 42 burned ostrich egg shell fragments that were believed to have been used as water vessels.
They also discovered 22 white calcite crystals, each the size of a palm tree or smaller, that are believed to have a ritualistic purpose.
In southern Africa, archaeological evidence of early Homo sapiens was found mainly in coastal locations.
The spread of artifacts in rock protection dates back 105,000 years and is as old as any coastal town. Their discovery has experts who question the long-held belief that civilization originated on the coast
That led researchers to believe that we as a species originated there, said Jayne Wilkins, a paleoarchaeologist at the Australian Research Center for Human Evolution at Griffith University in Queensland, Australia.
Ga-Mohana Hill is more than 370 miles from the coast, but her analysis, published March 31 in the journal Nature, dated the artifacts to be approximately 105,000 years old.
Distribution of ostrich egg shells in South African archaeological sites 50,000 to 200,000 years ago
That makes them contemporary with some of the oldest items found on the South African coast.
“Our results from this rock shelter show that overly simplified models for the origins of our species are no longer acceptable,” said Wilkins.
“There is evidence that many regions on the African continent were involved, the Kalahari being just one.”
With so few archaeological sites going back that far, it is not clear whether developments in human activity took place in one region and were brought to another, or originated independently in different locations.
The finds are remarkable, she explains, because “there were very few well-preserved, datable archaeological sites in the interior of southern Africa that can tell us about the origin of Homo sapiens.”
By the time the eggshells would have been used, the southern Kalahari was receiving enough rainfall to provide water sources to people year-round, Science News reports.
Wilkins’ team traced the chronology of stone tools (pictured) and other items at the Ga-Mohana Hill North Rockshelter using luminescence dating, which measures the natural light that collects in tiny grains of quartz and feldspar
Wilkins’ team tracked the chronology of items in the Ga-Mohana Hill North Rockshelter using a technique called luminescence dating, which measures natural light signals that accumulate in tiny grains of quartz and feldspar.
“You can think of each grain as a miniaturized clock from which we can read this natural light or luminescence signal that tells us the age of the archaeological sediment layers,” said co-author Michael Meyer, geologist at the University of Innsbruck in Austria.
The process dated the deposit to about 105,000 years.
“This suggests that the early humans in the Kalahari were no less innovative than they were on the coast,” said Wilkins.
The researchers found the likely source of the calcite crystals about 1.5 miles from the Ga-Mohana North Rockshelter
Artifacts found during coastal excavations have been dated 125,000 to 70,000 years ago, including a 100,000-year-old “art studio” on South Africa’s South Cape coast that houses charcoal, grindstones and ocher-filled seashells.
While the crystals are unchanged, the team’s analysis shows that they did not end up naturally in the sediment, but were purposely collected objects that are likely associated with spiritual beliefs and rituals, Wilkins said.
They located the likely source of the calcite about 1.5 miles from the Ga-Mohana North Rockshelter.
Before their research, the oldest crystals used by humans were from around 80,000 years ago and were in another South African rock shelter.
An archaeological dig at Ga-Mohana Hill North Rockshelter that found early evidence of complex behavior in Homo sapiens. Local hunters and gatherers still use the shelter for ritual activities today
Local hunters and gatherers still use Ga Mohana Hill for ritual activities today, revealing a continuity that researchers call “remarkable”.
“Many who visit Ga Mohana Hill today for ritual practice see it as part of a network of places associated with the Great Water Serpent (Nnoga ya metsi), a moody and shape-changing being,” wrote Wilkins in The Conversation.
“Places like Ga-Mohana Hill and the stories associated with it are still some of the most enduring intangible cultural assets of the past, connecting modern Indigenous South Africans with earlier communities.”
The name “Kalahari” comes from “kgalagadi”, a word in the South African Tswana language, which means “a waterless place”.
While technically not a true desert – it receives too much rainfall to qualify – there are broad swaths with no permanent surface water.