Researchers from the Weizmann Institute of Science have found one of the earliest known examples of the controlled use of fire. The non-visual findings are estimated to date back to 800 years ago. It is estimated that ancient hominins used fire until 1 million years ago, when Homo habilis began to pass on to Homo erectus.
Fire, dubbed the 'cooking hypothesis', was believed to have been instrumental in our evolution to cook food, not only allowing hominins to stay warm, make weapons and fend off predators, but also eliminate pathogens and increase the digestion and nutritional value of food.
The only problem with this theory is the lack of data. Traditional methods have only been able to reveal evidence of widespread fire use no older than 200.000 years, because finding archaeological evidence of pyrotechnology primarily depends on visual identification of changes (primarily a color change) resulting from the burning of objects.
While there is some evidence of fire dating back 500.000 years, it is still insufficient as only five archaeological sites worldwide offer reliable evidence of early fire.
Researchers from Weizmann's Department of Plant and Environmental Sciences have previously discovered evidence of controlled burning on stone tools in Israel, using groundbreaking technology that combines artificial intelligence and spectroscopy, dating back 200.000 to 420.000 years.
The same method was used to assess the heat exposure of artifacts discovered at the Paleolithic Evron Quarry in Western Galilee, which contains stone tools and animal fossils from 800.000 to 1 million years old.
According to the findings, 26 flint tools were heated to various temperatures, some exceeding 600°C. Additionally, when the scientists analyzed 87 faunal remains using a different spectroscopic technique, they found that the extinct elephant's tusk also showed structural changes brought on by warming.
"By looking at archeology from a different perspective, using new techniques, we can find much more than we initially imagined," the research team said. The techniques they created can be used, for example, to find non-visual signs of fire use elsewhere. In addition to Lower Paleolithic settlements, this approach could provide a new spatio-temporal perspective on the evolution and regulated use of fire, enabling us to understand how hominin pyrotechnic-related behaviors changed over time and influenced other behaviors.