A field in eastern England has revealed evidence of the earliest known instance of humans creating and controlling fire, a significant find that archaeologists say illuminates a dramatic turning point in the human story.

In Barnham, Suffolk, the discovery of baked earth that formed a hearth, heat-shattered flint axes and two fragments of pyrite — a type of stone used to create sparks for lighting tinder — indicates that early humans, most likely Neanderthals, were able to make and maintain fires.

“This is a 400,000-year-old site where we have the earliest evidence of making fire, not just in Britain or Europe, but in fact, anywhere else in the world,” said Nick Ashton, curator of Palaeolithic collections at the British Museum in a news briefing. Ashton is senior author of a study on the Barnham site that was published Wednesday in the journal Nature.

“It’s the most exciting discovery of my 40-year career,” he added.

When and where humans began deliberately making fire and cooking food are among the biggest questions that have long stumped researchers of human origins.

The ability to make a fire would have allowed the humans living at Barnham to keep warm, deter wild animals and routinely cook their food, which would have made it more nutritious. And being able to control the fire could have brought practical benefits, such as the development of adhesives and other technologies, and provided a focus for social interaction such as storytelling.

The artifacts uncovered at the site are 350,000 years older than the previous known evidence of fire-making in the archaeological record, which was from a site in northern France. Ashton noted, however, that it’s unlikely the ability to light a fire first emerged at Barnham.

“I think many of us had a hunch that there was regular use of fire in Europe around 400,000 years ago. But we didn’t have the evidence,” Ashton said.

Determining how and when humans first learned to master fire is challenging for archaeologists. Evidence of fire rarely survives. Ash and charcoal can easily be blown away and baked sediments can erode. It’s also difficult to distinguish been a natural and human-made fire.

For example, artifacts indicate the presence of fires at sites inhabited by humans in Israel, Kenya and South Africa that date from 800,000 years to more than 1 million years ago, according to the study. However, it’s difficult to rule out the possibility they were wildfires that weren’t started by humans.

Early humans probably began harnessing fire caused by lightning strikes or other natural causes, perhaps by conserving embers for a period of time, but it would have been an unpredictable resource, according to the study.

The finds at Barnham, however, suggest that its inhabitants were able to routinely and deliberately light and use fire.

Smoking gun

The team analyzed the reddened sediment from Barnham and determined its chemical properties differed from those you would expect in a natural fire. For example, the signature of hydrocarbons suggested higher temperatures from the focused burning of wood, rather than landscape-wide burning. Mineral alteration of the sediment also suggested repeated burning at the same location.

However, the smoking gun was the two pieces of iron pyrite, sometimes called fool’s gold, which can be used to strike flint, creating sparks that could have lit tinder such as dry fungus. The naturally occurring mineral wasn’t available in the immediate environment, suggesting that these people understood its fire-lighting properties and had sought out the mineral, the researchers reported in the study.

What is impressive about this research is the wide range of analytical methods brought to bear on the problem, said John McNabb, a professor of palaeolithic archaeology at the Centre for the Archaeology of Human Origins at the University of Southampton. He wasn’t involved in the study.

“Fire brings many benefits. It can be a tool for defence. It can help make your food more nutritious. It can extend the day and make your working time more productive for longer. Fire can help bind individuals into societies,” McNabb said via email.

“But if you do not control it, then you are still at the mercy of the landscape —– all its benefits may be transient. Control fire and you begin to control the world around you.”

The flint axes confirm human presence at the site although no hominin bones have been found at Barnham. Study coauthor Chris Stringer, research leader in human evolution at the Natural History Museum in London, said that early Neanderthals were known to have lived about 80 miles away in Swanscombe, Kent, at the same time period, making them the most likely candidate to have made fire at the site. They likely came to Britain from Europe, which at that time was connected by a land bridge, he said.

“One of the interesting aspects now is to use the techniques that have shown fire-making at Barnham and see whether, if we look at other sites in more detail, we can even find the same thing at other sites in in Britain, in Europe, maybe even beyond,” Stringer said.

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