Researchers working with artifacts uncovered from a cave in Israel reveal that humans only began using fire habitually 350,000 years ago in the Middle Pleistocene. The findings, published in the Journal of Human Evolution this month, could also help explain certain aspects of our anatomical evolution over the last few million years.
The earliest evidence of fire use in our lineage date back to more than a million years ago, but it wasn’t much good for survival, cooking, or even fire-side story telling until we made a habit of it. So when did occasional fire use change into something routine and planned?
To find a time frame for this “technological mutation,” an international team led by Ron Shimelmitz from the University of Haifa examined previously excavated flints (stone tools for cutting and scrapping) and flint debris from a 16-meter deep sequence of deposits at Tabun Cave in the limestone cliffs of Mount Carmel in northern Israel. “Tabun Cave is unique in that it’s a site with a very long sequence,” Shimelmitz tells Science. “We could examine step by step how the use of fire changed in the cave.” The cave was inhabited for at least half a million years, and in some layers, the flints showed clear signs of fire exposure: They were blackened or red in color, cracked, and had little round dips where fragments flaked off in a characteristic way. The flints from layers older than 350,000 years didn’t appear burned.
Based on the increase in the frequency of burnt flints—together with previous archaeological data from this region, such as burned flints, bones, and ash in the Qesem Cave in Tel Aviv—the team found that regular fire use developed between 350,000 and 320,000 years ago in the eastern Mediterranean. That’s far enough back to have shaped our culture, Science reports, but too recent to explain our big brains or our expansion into regions with colder climates.
“Regular use of fire changed hominin existence and influenced the direction of evolution in our lineage in a diversity of ways,” Shimelmitz tells the Daily Mail. "The benefits of fire for processing food, altering raw materials or enhancing social interactions would be fully realized only when use of fire shifted from opportunistic and occasional to habitual and regular.”