Researchers at Heriot-Watt University in Scotland have discovered that early humans in Europe were making fire at least 50,000 years earlier than previously believed, as detected at Valdocarros II, an archaeological site near Madrid in Spain.

Published in the journal Scientific Reports, the scientists' research shows evidence that fires for activities like cooking, heating, and defense were used not 200,000 but 250,000 years ago.

Molecules of incomplete burning were identified by using forensic chemical methods by the research team at Heriot-Watt's School of Energy, Geoscience, Infrastructure, and Society.

Assistant Professor at Heriot-Watt, Dr. Clayton Magill, a specialist in using geochemistry (the study of the chemical composition of the earth and its rocks and minerals) to reconstruct ancient environmental conditions, worked in collaboration with Spanish archaeologists Susana Rubio‑Jara and Joaquín Panera of the Complutense University of Madrid.

Dr. Magill explained: "We have found definitive evidence of things being burnt and those remains are organized into a pattern, suggesting it's humans who are making and controlling the fire. Either they were using the fire to cook or to defend themselves. The spatial patterning in the fire tells us that they were encircling something, like a home or sleeping area, a living room or kitchen, or an enclosure for animals."

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Dr. Magill called the findings "very exciting" and that they close a gap in understanding human-controlled fire and human development. 

"This is important because our species is defined by our use of fire," Dr. Magill said, explaining that "being able to cook food to feed our big brains is one of the things that made us so successful in an evolutionary sense. Fire also brings protection and fosters communication and family connection. And we now have definitive, incontrovertible evidence that humans were starting and stopping fires in Europe about 50,000 years earlier than we suspected."

According to Dr. Magill, chemical analysis is more reliable to confirm fire than analyzing remains in archaeological hearths because they can be disrupted by weather conditions or the extraction process. 

The next step includes studying stone tools found near fire hearths to investigate the different ways in which they were used to control the fire, for example, to cut meat or pulverize plants.

"We want to understand whether the selective or specialized use of tools is something that should go at least theoretically hand-in-hand with fire control," Magill clarified. 

The oldest clear evidence of human-made fire lies in East Africa about 1.5 million years ago and in Palestine about 790,000 years ago. In Europe, countries including Hungary, France and Germany have been linked with previous evidence of fire-control as well. 

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