Almost half a million years ago, archaic humans picked up conveniently shaped flints that required only a few more whacks to shape into a perfect tool. The convenient shape was not coincidence: They were reworking cruder stone tools or cores that had been made even earlier, possibly by even more archaic humans. This was true recycling, archaeologists argue, with proof of the practice in numerous Paleolithic sites in the Levant, Europe and Africa.
But the trail ran cold after the Paleolithic. Now, though, archaeologists at Tel Aviv University and Ohio State University report evidence of flint recycling at Ein Zippori hundreds of thousands of years later — during the Neolithic Age, when modern civilization was forming, and as late as the Bronze Age.
Ein Zippori was a fertile site in the Galilee within a topographical basin a mile west of Nazareth. Watered by the Zippori stream, the place has been occupied since time immemorial through to the Byzantine period. It was excavated by Dr. Ianir Milevski and Nimrod Getzov on behalf of the Israel Antiquities Authority.
So there was a yawning gap of hundreds of thousands of years in the story of lithic (stone) recycling. But writing in the Journal of Lithic Studies, the team headed by Profs. Avi Gopher and Ran Barkai suggests that reworking stone tools wasn’t some prehistoric spasm of sustainability in the Paleolithic that died out, to be reinvented only in the Neolithic.
The practice of recycling was probably maintained until stone tools went out of fashion during the age of metal, Barkai posits in the paper with Gopher, Yoni Parush and Bar Efrati of Tel Aviv University and Prof. Richard Yerkes of Ohio State University.
While the practice of recycling remained essentially the same over the millennia, the technology of knapping itself had advanced throughout the hundreds of thousands of years: In the Neolithic Age, the knappers were recycling old stone flakes into artifacts as sharp as scalpels.
In Israel, recycled flints from the Lower Paleolithic around 400,000 years ago were found at Tabun Cave in the north and Qesem Cave, right by Tel Aviv.
Evidence of lithic recycling was also identified in the Upper Paleolithic caves at Kebara and Hayonim; most of the tools found there were made from scratch, but some showed the hallmarks of reworking. Paleolithic sites featuring lithic recycling were also found in Spain and Italy.
These Lower Paleolithic recyclers were not Homo sapiens: our species’ evolution in Africa had barely begun.
Recycling may have continued as late as the Iron Age as well. “People continued to use stone tools even in the Iron Age,” Barkai points out: not everybody could afford, or even obtain, the newfangled metal implements.
But how could it be that nobody found indicators of recycling between the Paleolithic and Neolithic ages until now? Maybe they didn’t look for any or notice them. To this day, new species are reported that had been there all along and went unnoticed — including a 100-foot (30-meter)-tall tree in the Andes, a monkey, a lot of frogs and a snail-sucking snake. Failing to realize that a given flint tool had been recycled is relatively understandable compared with the sudden discovery of a giant Madagascan palm tree unknown to science.
Which begs the question of how exactly archaeologists recognize that a tool has been recycled. The researchers look for two clues: Evidence of a time lapse; and a change in function between the original tool and the later (recycled) one.
Sometimes, change leaps to the eye. Stone tools abandoned in certain conditions become patinated: a glossy, thin mineral coat forms on the exterior. (Think of Roman glass jewelry with pretty blue-green patination, though do note that if you wash them, bye-bye beauty.)
Exposed metal surfaces, stone axes and even wood can become patinated over time, given the right conditions. Even a layman can tell if a patinated ax was reworked to sharpen its edges or whatever — the newly exposed surfaces are naked rock not coated in shiny blue and green.
Another question is why the ancients recycled. For this, Barkai and the team suggest several possible impetuses.
Making a better tool
Making flint tools from scratch is hard work. It makes intuitive sense that prehistoric manufacturers would avail themselves of conveniently shaped rocks — which, whether they realized it or not, could have been older, rougher stone tools or contemporary broken ones. Then the knappers would rework them, creating sharp edges, knocking off razor-edged flakes and ending up with a better stone tool.
The team defines recycling as a behavior implying successive cycles of modification and use of an artifact for different purposes, with a phase of discard between them.
Anyway, the gap in the evidence between the Paleolithic and the age of metal dismays Barkai not even slightly. He thinks that recycling flint — and certain other aspects of prehistoric living — was probably a continuous behavioral pattern.
One possible reason for recycling that leaps to mind is scarcity of raw material. But there is not, and never was, a shortage of flint in Israel, let alone at Ein Zippori. Millions and millions of years ago this land was a seabed, which is where flint forms. Today, flint commonly appears as veins and nodules in the chalky local rocks, and isolated flint stones litter the ground.
So, Barkai and the team deduce that systematic production of flakes from discarded tools or cores (blanks) wasn’t driven by the scarcity of flint. The reasons for recycling include, they believe, creating new functions for old tools (or creating tools to achieve new purposes), and possibly sociocultural aspects as well.
“Recycling can produce types of tools that can’t be made any other way,” Barkai tells Haaretz.
When you smash a great hunk of flint (a core) with a hammerstone, the flakes you knock off have two faces: the external dorsal side, and the internal ventral side. Inevitably, where the hammerstone touched the flint core, a percussion bulb forms on the dorsal side of the flake — like a small hill. But the ventral face of the flake is smooth.
If you want a super-sharp, state-of-the-Stone-Age-art flake or blade with two smooth faces, you need to recycle, Barkai explains. “Recycling involved taking a preexisting flake and removing tiny new flakes from the ventral face,” he says. “Those flakes have two ventral-type faces.”
These recycling output flakes were especially sharp, especially convenient to hold, Barkai says, and were used for very delicate things. And thus, recycling also produced a much wider variety of stone tools.
What they were doing with wood
Change in function is another matter, which brings us to point out that we don’t actually know what stone tools were used for.
We can be confident that stone axes had been used to cut down trees, Barkai says. But that’s where the certainty largely ends.
However, clues can be found with the help of microwear analysis, which Yerkes, Barkai, Parush and Gopher describe in a separate paper also published in the Journal of Lithic Studies regarding the recycled artifacts found at Ein Zippori.
The Neolithic culture at Ein Zippori that produced the recycled tools is called the Wadi Rabah culture. It existed throughout Israel, Lebanon and Jordan (and is thought to have possibly invented the slingstone in the late Neolithic or early Chalcolithic, as described by Prof. Danny Rosenberg in 2009).
The Wadi Rabah peoples made advanced stone blades and flakes, adzes and chisels and other bifacial tools, stone sickles, as well as some arrowheads, though they didn’t hunt for sustenance by that point in time: they farmed. The Ein Zippori collection from the Early Bronze Age includes much the same tools as elsewhere in the southern Levant from that period: retouched flakes, blades, sickles and even meticulously serrated tools called denticulates; also elaborate awls and borers, burins and scrapers, the team writes. (A burin is a flake with a chisel-like edge that was apparently used for engraving or for carving wood or bone.)
So, specifically, the team deduced by microwear analysis that almost half the recycled flakes they found at Ein Zippori from the Neolithic period had been used in butchery — to cut and scrape meat and fresh hide; 20 percent were used to work wood; and a small fraction was used both for butchering and working wood.
What were they doing with wood? “Heaven knows,” Barkai answers, and adds: “We know they were working wood at Gesher Bnot Yaakov” — a site dating to around 800,000 years ago.
The thing is, barring extraordinary conditions, wood isn’t preserved. Maybe a clue lies in the gigantic humanoid wood figurine found in Shigir, Siberia, from 11,500 years ago (the oldest wooden idol found to date was preserved because it fell into a peat bog). It was around 17 feet tall and had to have been carved with stone tools.
Maybe the Neolithic peoples of the Levant were making wood idols too? They were certainly making figurines out of stone, and using wood might have been a lot easier. It just wouldn’t keep.