Thousands of stone tools crafted 40,000 – 45,000 years ago (early Upper Paleolithic) and unearthed from the recently discovered cave site of Mughr el-Hamamah in Jordan show a mix of techniques for making points, blades, scrapers, cutting flakes, and reveal clues about how early humans may have started organizing into complex social groups by specializing in different technical skills.
Two stone tool points made using a prismatic blade technique (left and center), and a bone point or needle (right). The finds give anthropologists a new window onto a transitional time, on the cusp of modern human cultural behaviors. Image credit: Emory University.
The Mughr el-Hamamah, or Cave of the Doves, is located in a limestone outcrop 240 feet above sea level. It overlooks the Jordan Valley, opposite the Nablus Mountains in the West Bank. The cave is about 30-feet deep with an entrance about 20-feet wide.
The excavations of the cave, in 2010, were headed by Dr Aaron Stutz and his wife, Dr Liv Stutz, both from Emory University.
The Upper Paleolithic layer of the cave included fireplaces stacked atop one another that yielded chunks of well-preserved charcoal from hearths associated with the tools.
Drs Aaron Stutz and Liv Stutz and their colleagues derived radiocarbon dates for the charcoal specimens, using advanced techniques that minimized the chances of contamination.
“We have achieved remarkably accurate estimates of 40,000 to 45,000 years ago for the earliest Upper Paleolithic stone tools in the Near East. Our findings confirm that the Upper Paleolithic began in the region no later than 42,000 years ago, and likely at least 44,600 years ago,” said Dr Aaron Stutz, who is the first author on the study published June 12 in the Journal of Human Evolution.
“We can speculate that several families shared the space and worked alongside one another. We found burned animal bones, so they were likely roasting meat, and perhaps boiling plants in hides suspended over their fires as they sat nearby making tools.”
“From the mouth of the cave, they would have had a commanding view of what was likely wetlands and open-vegetation terrain. They could see approaching visitors and deer and gazelle wandering in the distance. If their kids were playing outside, they might also be watching for leopards or other predators.”
Toolmaking was a major activity of the group at Mughr el-Hamamah, as evidenced by their prolific output.
“We don’t know if these toolmakers were mainly Neanderthals or anatomically modern humans, but recent evidence from other studies now raises the possibility that they were a mix of different populations. What we see at the Mughr el-Hamamah site is that individuals were starting to live, work and form families in larger, more culturally structured social networks,” Dr Aaron Stutz said.
He added: “Mughr el-Hamamah toolmakers appear to have achieved a division of labor that may have been part of an emerging pattern of more organized social structures.”
“The theory that greater social division of labor was important at this prehistoric juncture was first put forward by anthropologists Steven Kuhn and Mary Stiner.”
“Our work really seems to support that idea. The finds from Mughr el-Hamamah give us a new window onto a transitional time, on the cusp of modern human cultural behaviors, bridging the Middle and Upper Paleolithic.”
This time also marked the ebbing of Neanderthals as a last wave of anatomically modern humans spread out from Africa and into the Near East. This region, also known as the Levant, comprises the eastern Mediterranean at the crossroads of western Asia and northeast Africa. As the final surge of modern humans passed through the Levant, they would likely have encountered human populations that arrived earlier, and they may also have interbred with Neanderthals.
Many discoveries of Near Eastern tool assemblages dating prior to the early Upper Paleolithic show that humans focused on just one technology. The Mughr el-Hamamah toolmakers, however, used different technologies to get different tools.
“They were investing in the kinds of activities that require maintaining relationships and group planning. They were gearing up for a clearly defined division of labor, including firewood gathering, plant gathering, hunting and food foraging,” Dr Aaron Stutz said.
“They produced large quantities of blades for knives, and for hafting onto spears, using a prismatic blade technique that yields long, narrow points that are nearly identical. This standardization minimizes waste of the rock while maximizing the end product. It’s the conceptual forerunner to assembly-line production.”
Artifacts from Mughr el-Hamamah also included scraping tools, made on thick blades for hafting onto a handle and likely used for working wood and animal hides. Other tools continued to be crafted with what is known as the Levallois technique, which was more often used to make the multi-use flakes and triangular points so common in earlier periods.
“It is not yet known if the few fragments of human bones found at Mughr el-Hamamah have left enough intact fragments of DNA for any genetic analysis. But the diverse tool technologies, in use throughout the occupation period of the cave, support the theory of hunter-gatherer populations starting to band together in larger, more interconnected social networks.”
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Aaron Jonas Stutz et al. Early Upper Paleolithic chronology in the Levant: new ABOx-SC accelerator mass spectrometry results from the Mughr el-Hamamah Site, Jordan. Journal of Human Evolution, published online June 12, 2015; doi: 10.1016/j.jhevol.2015.04.008
