A team of Israeli scientists has discovered evidence of continued fire building beginning around 300,000 years ago. The discovery goes a long way toward answering the question of when humans began to control fire and use it for their daily needs – which is central to understanding the rise of human culture.



The evidence of fire building was discovered in the Qesem Cave, an archaeological site near present-day Rosh Ha'ayin, by a team headed by professors Avi Gopher and Ran Barkai of Tel Aviv University. Their findings were published recently in the Journal of Archaeological Science.



Also involved in the project from its beginning in 2000 was Dr. Ruth Shahack-Gross of the Kimmel Center for Archeological Science at the Weizmann Institute, whose expertise is in the identification of archaeological materials.



Shahack-Gross identified a thick deposit of wood ash in the center of the cave. Using infrared spectroscopy, she and her colleagues were able to determine that mixed in with the ash were bits of bone and soil that had been heated to very high temperatures - conclusive proof that the area had been the site of a large hearth.



To test the micro-morphology of the ash, Shahack-Gross extracted a cubic chunk of sediment from the hearth, hardened it in the lab and sliced it into extremely thin slices – so thin they could be placed under a microscope to observe the exact composition of the materials in the deposit and reveal how they were formed.



She was able to distinguish a great many micro-strata in the ash – evidence of a hearth that was used repeatedly over time. Around the hearth area, as well as inside it, the archaeologists found large numbers of flint tools that were clearly used for cutting meat.



By contrast, the flint tools found just a few meters away had a different shape, designed for other activities.



Also in and around the area were large numbers of burnt animal bones – further evidence for repeated fire use for cooking meat. This organization of various "household" activities into different parts of the cave points to an organization of space – and a thus kind of social order – that is typical of modern humans.



"These findings help us to fix an important turning point in the development of human culture, in which humans first began to regularly use fire both for cooking meat and as a focal point – a sort of campfire – for social gatherings," says Shahack-Gross.



"They also tell us something about the impressive levels of social and cognitive development of humans living some 300,000 years ago."



The researchers think that these findings, along with others, are signs of substantial changes in human behavior and biology that commenced with the appearance in the region of new forms of culture – and indeed a new human species – about 400,000 years ago.



Open gallery view Scan of a sediment "slice" from the hearth area of the cave, showing burnt bone and rock fragments within the gray ash residue. Credit: Weizmann Institute of Science