A method of Stone Age tool production is believed to have its origins in Africa but findings of a new study challenges this notion with evidence that suggests different populations around the world independently developed their tool-making skills during the Paleolithic Era.

Scientists have argued that a tool-making technology known as the Levallois technique was invented in Africa and that the method eventually spread to Eurasia following the migration of humans from Africa. An analysis of stone artifacts in Armenia, however, suggests otherwise.

In a new discovery described in the journal Science on Sept. 26, a group of researchers examined almost 3,000 stone artifacts that were excavated from Nor Geghi 1 (NG1), an archeological site in Armenia that was preserved by two lava flows. By analyzing and dating the volcanic ash between these lava flows, the researchers found that the artifacts at the site existed between 200,000 and 400,000 years ago, the era associated with the earliest Levallois tools in Africa.

The researchers also found that the people who lived in the area thousands of years ago used both Levallois and a more rugged tool-making method called bifacial technology at the same time providing the earliest evidence that these technologies existed together and suggesting that the people there may have gradually developed Levallois technique from bifacial technology.

"We wouldn't have found this mixture if the Levallois technology had simply replaced the old method," said study researcher Daniel Adler, from the University of Connecticut in Storrs. "The communities probably worked out for themselves how to make bifacial tools and then it was a short step to the Levallois method." 

Study researcher Simon Blockley, from the Department of Geography at the Royal Holloway, University of London, said that the artifacts has helped shed light on the evolution of Stone Age tools at a time when humans underwent profound biological and behavioral changes.

He said that the people who live at the site thousands of years ago appear to be more innovative than they were given credit for as they have utilized a duo of different tool-making technologies to come up with tools that are crucial for mobile hunter-gatherers during the period.

 "Our findings challenge the theory held by many archaeologists that Levallois technology was invented in Africa and spread to Eurasia as the human population expanded," Blockley said. "We now have the first clear evidence that this significant development in human innovation occurred independently within different populations."