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Humans have been controlling fire for at least 300,000 years onlinecollegedegreee.blogspot.com

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onlinecollegedegreee.blogspot.com Humans have been controlling fire for at least 300,000 years

Humans have been controlling fire for at least 300,000 years


Archaeologists working at Qusem Cave in Israel have uncovered a 300,000 year-old hearth. It's the earliest evidence of repeated fire building over a continuous period by humans.


Anthropologists estimate that humans first discovered fire about a million years ago. What we don't know, however, is when our ancestors first starting using it on a regular basis, for example, to cook meals. But the discovery of a 300,000 year-old hearth at an archaeological site near Tel Aviv sets the clock to at least that far back in time.


The findings, now published in the Journal of Archaeological Science, show that the hearth was 6.5 feet in diameter at its widest point and used repeatedly over time. In addition to the hearth, the cave in which it was found contained a thick deposit of wood ash at its center. And using infrared spectroscopy, the archaeologists determined that bits of bone and soil that had been heated to very high temperatures were mixed in with the ash.


Humans have been controlling fire for at least 300,000 years S


Further testing showed a great many micro-strata — a sign that the hearth was used repeatedly over time.


The area also contained large numbers of flint tools that were used for cutting meat and large numbers of burnt animal bones. The layout of the cave also indicated that it was a sort of base camp that a large group of prehistoric humans returned to repeatedly.


"These findings help us to fix an important turning point in the development of human culture — that 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," noted lead archaeologist Ruth Shahack-Gross in a statement. "They also tell us something about the impressive levels of social and cognitive development of humans living some 300,000 years ago."


The researchers theorize that these findings are signs of substantial changes in human behavior and biology that started with the appearance in the region of new forms of culture about 400,000 years ago.


[ Weizmann Institute | Top image: Quest for Fire; inset image: Shahack-Gross et al. ]


onlinecollegedegreee.blogspot.com Humans have been controlling fire for at least 300,000 years