“Major” archaeological developments could help rewrite early human history

An innovative technique used in a study of Neanderthal hearths – places where fires started – has been described by researchers as a ‘major’ development in archaeology, one that could help shed light on the behavior of prehistoric people.

For a study published in the journal Naturean interdisciplinary team of researchers has discovered that a series of six Neanderthal hotspots at El Salt, a Paleolithic site in Spain, formed over at least 200 to 240 years, with each likely emerging decades apart.

The findings are important because determining the timescale of human activity in the Paleolithic, also known as the Old Stone Age, has long been one of the most challenging problems in prehistoric archaeology. (This period in human prehistory extends from the earliest use of stone tools, more than 3 million years ago, to about 12,000 years ago.)

Determining the time scale of such activities is difficult, largely due to the limitations of dating techniques. For example, radiocarbon techniques cannot date samples older than about 50,000 to 60,000 years. Meanwhile, other techniques can produce errors of several thousand years.

“Although it has been proposed that Paleolithic hunter-gatherers were highly mobile, important aspects of their lifestyle, such as the time between camps and the size of traveling groups, remain unclear,” the study authors wrote. “The complexity of the formation of Paleolithic sites makes it difficult to distinguish episodes of human occupation and resolve the time between them.”

In the latest study, the research team – led by Ángela Herrejón-Lagunilla from Spain’s University of Burgos – attempted to tackle this problem by using an innovative technique to examine the hearths at El Salt, which dated back about 52,000 years ago.

The technique involved a combination of ‘archaeostratigraphic’ analyzes – which helped the team determine the order in which the hearths were created, based on their relative position in the ground layers – and an approach known as archaeomagnetic dating.

This technique studies and interprets signatures of Earth’s past magnetic field, as recorded in burned archaeological remains. The approach works, as burned materials record the direction and/or intensity of the magnetic field at the time of the last fire.

Combining the two approaches revealed that the Neanderthal hotspots at El Salt emerged decades or even a century apart – a finding that sheds light on the behavior of these early humans, who went extinct about 40,000 years ago. The results provide an indication of the timing of the foci in unprecedented resolution.

“When we excavate archaeological settlement areas, we assume that they are the result of many events of human activity, but until now we did not know exactly how much time had passed between these activities. We didn’t know if it was decades, centuries or thousands of years,” Santiago Sossa-Ríos, a researcher in prehistory, archeology and ancient history at Spain’s University of Valencia and author of the study, said in a press release.

“From there, within this temporary framework, we can open new lines of research to study, for example, mobility patterns, technological changes or differences in the use of space,” he continued. “The time has come, the challenge lies in combining and extracting everything the methods offer us to uncover.”

Hearths can provide useful information about Neanderthal life because they are good indicators of occupation at a particular location.

The new findings indicate that although Neanderthals were highly mobile, in some cases they returned to previous settlements after long periods of time, but still within the span of individual lifetimes.

In Paleolithic archaeology, a discipline in which human behavior is usually studied on long timescales typical of geological processes, being able to observe changes on timescales closer to a human lifespan is an important development.

As a result, the techniques used in the study could help shed light on Paleolithic hunter-gatherers. They can even be applied to other archaeological contexts to determine the timing of human activity.

“It is definitely a major step forward in archaeology, which will help us better understand human behavior in the past,” the study authors said in the press release.

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