A 'Carpet' of Ancient Stone Tools Uncovered in the Sahara

It's an archaeologist's dream come true: a new intensive study of a massive outcrop of sandstone in the middle of the Saharan desert has revealed that it is covered in ancient stone tools, with an average of 75 distinct tools per square meter.

They are calling the massive archaeological site at the Messak Settafet escarpment a "carpet" of ancient tools, or a "man-made landscape" long before asphalt and roads existed.

So what just made this region such a historic treasure trove? Experts are suggesting that early humans have been discarding the tools they used here for over hundreds of thousands of years, and because there is little rain or wind to break these tools down or wash them away, they have simply built up over time.

And while the occasionally discarded piece of hand-chipped stone doesn't sound like it could amount to much, initial surveys of the escarpment have estimated that there are 75 million tools and other archaeological objects per square kilometer. The Messak Settafet runs a total length of 350 kilometers, and can get as wide as 60 km - that's a mind boggling number of tools just laying around in the sand. (Scroll to read on...)

"The Messak sandstone, now in the middle of the vast sand seas of Libya, would have been a high quality rock for hominins to fracture - the landscape is in effect a carpet of stone tools, most probably made in the Middle and Upper Pleistocene," Robert Foley of the University of Cambridge, who studied the escarpment with colleague Marta Mirazón Lahr, explained in a statement.

The results of their work were recently published in the journal PLOS One.

Mirazón Lahr added that although experts are theorizing the Anthropocene - when humans began to truly impact the environments they inhabited - may have been up to 10,000 years ago (when forest clearing and agriculture began), a small impact may have began much earlier.

"Making stone tools dates back more than two million years, and little research has been done on the impact of this activity," she said. "The Messak Settafet is the earliest demonstrated example of the scars of human activity across an entire landscape; the effects of our technology on the environment may be considerably older than previously thought."

The simplest of the tools were opportunistically hacked from the stone, leaving "bulbs of percussion" where they were chunked out. At a more complex level, the researchers found evidence that ancient humans went at boulders and outcrops with specifically designed tools, looking to split stone in just the right way. (Scroll to read on...)

"It is clear from the scale of activity how important stone tools were, and shows that African hominins were strongly technologically dependent," explained Foley. "Landscapes such as these must have been magnets for hominin populations, either for 'stone foraging trips' or residential occupation."

They suspect it was regions like this escarpment that made humans truly successful in the aptly named Stone Age.

"Hominins may well have become tethered to these areas, unable to stray too far if survival depended on access to the raw materials for tools, and forced to make other adaptations subservient to that need," added Mirazón Lahr.

This could be an important revelation about the Age, helping archaeologists more accurately theorize where early humans traveled and thrived.

The research pair even went as far as to use their surveys of the Messak Settafet to conduct an estimate of how much tool manufacturing went on throughout the whole of human evolution in Africa. They estimate an average density of between 0.5 and 5 million stone artifacts per square kilometer of Africa were crafted - the rough equivalent of up to 84 million Great Pyramids of Giza.

The takeaway? Our ancestors REALLY liked their tools.

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