Rediscovered in Ukraine: Stone Tools Suggest Earlier Human Arrival in Europe

Ancient stone tools discovered in Korolev in western Ukraine could represent the oldest known evidence of human presence in Europe. Made from volcanic rocks, these tools were excavated from quarries in the 1970s. With state-of-the-art methods, scientists determined the sediment layers surrounding the tools are 1.4 million years old.

“This is the earliest evidence of humans in Europe,” said Mads Faurschou Knudsen, a geophysicist at Aarhus University in Denmark and co-author of the research. He added it's uncertain which human species created these tools, but it's likely it was Homo erectus, the first of our cousins to walk upright.

The description and results of the research were published in the journal "Nature."

In the distant past, our ancestors fashioned simple knives and scrapers by striking one stone against another, just like their predecessors in Africa. These tools were used for cutting meat or scraping leftovers from animal skins. Such tools, along with other artifacts, were found at the site in Korolev.

The authors of the publication claim the found tools could be as old as 1.4 million years and provide valuable insight into how and when our first relatives arrived in Europe. They suggest these were likely members of the adaptable species Homo erectus, who arrived in Europe from the east and spread across the continent. “So far, there was no strong evidence for migration from east to west,” admitted Roman Garba, an archaeologist from the Czech Academy of Sciences in Prague, co-author of the study.

Initially, no one could accurately date the artifacts. But over time, technology has significantly advanced, and new methods have emerged. Garba and his colleagues employed a dating technique based on cosmogenic isotopes - rare isotopes generated when high-energy cosmic rays collide with elements in minerals on Earth's surface.

Changes in the concentrations of these isotopes can indicate how long ago the mineral was buried. By calculating the ratio of specific isotopes in the sediment layer where the tools were discovered, the team estimated they are about 1.4 million years old.

Until now, the earliest accurately dated evidence of hominins in Europe includes fossils and stone tools found in Spain and France, dating from 1.1 to 1.2 million years ago. The oldest stone tools of this type found in Eastern Africa are dated at 2.8 million years old.

The estimated dating period led researchers to speculate that Homo erectus, the only known human species to have lived outside Africa around 1.4 million years ago, could have made these tools. Furthermore, the tools from Korolev resemble those found at archaeological sites in the Caucasus Mountains, also linked to Homo erectus and dated at roughly 1.8 million years old. No remains were found at the Korolev site, so it cannot be stated with certainty that Homo erectus made these tools.

The discoveries provide a fuller picture of the likely routes taken by the first Europeans, confirming the view that they spread from east to west - possibly along the Danube valleys, the authors of the publication speculate.

Homo erectus had bodies similar to modern humans but significantly smaller brains. It appeared about two million years ago, as the fossil record suggests. Its knowledge of stone tool production and hunting techniques helped it become the first hominin known to spread beyond Africa. Traces of its existence can be found from today's England to the islands of Southeast Asia.

Some experts question the time range obtained in the studies, established at 1.4 million years. They highlight some issues with the research. “There is no clear chronology,” said Fabio Parenti, an archaeologist from the Federal University in Parana. He also added the artifacts are poorly described and, generally, in his opinion, the study is “quite weak”.

Giovanni Muttoni, a geochronologist from the University of Milan and an expert in paleomagnetic dating, shares Parenti's concerns. According to him, the primary expansion of hominins from Africa began about 900,000 years ago when glacial cycles became more intense and set entire food chains in motion. “The world changed 900,000 years ago. […] In my opinion, nothing particularly interesting from a climatic and ecological perspective happened 1.4 million years ago,” said Muttoni.

Other specialists suggest that dating should involve multiple methods using different geological clocks to increase confidence in the obtained results.

Research in Korolev has been halted due to Russia's aggression against Ukraine. However, scientists haven't lost hope and plan further excavations. They are also working on building a local museum and are applying for this site to be included on the UNESCO cultural heritage list.

Sources: Science, Nature, Live Science