Evidence suggests cultural exchange between Neanderthals and humans

While ancient DNA analysis has already revealed that Neanderthals and modern humans (Homo sapiens) interbred, one possible site of this may have been southern Türkiye. A research team including Associate Professor Naoki Morimoto of the Graduate School of Science at Kyoto University and Professor Ismail Baykara of Gaziantep University in Türkiye discovered fossils of both Neanderthals and modern humans from a single site during an excavation at Üçağızlı II Cave in southern Republic of Türkiye. The Neanderthal fossils dated from approximately 77,000 to 59,000 years ago, and the modern human fossils from approximately 59,000 to 47,000 years ago. However, their stone tool processing methods and the shells used as ornaments were identical, suggesting cultural exchange.

Morimoto stated: "Neanderthals looked distinctly different from modern humans, but they shared commonalities with them. There was evidence that both species made holes in the same Columbella rustica shell to create ornaments. From the Neanderthals' perspective, they might have felt a greater sense of familiarity with the nearby modern humans than with Neanderthals in far-off Europe." The findings were published in PNAS.

Modern humans emerged in Africa approximately 200,000 years ago. It is believed that they attempted to move from Africa to Europe 100,000 years ago but abandoned the attempt and later dispersed into the Eurasian continent (Out of Africa) from the Levant region (around southern Türkiye, Jordan, and Israel) approximately 60,000 years ago. The only evidence of this Out-of-Africa migration had been fragmentary fossils from approximately 55,000 years ago discovered in Israel.

On the other hand, Neanderthals, relatives of modern humans, diverged from the ancestors of modern humans approximately 500,000 years ago and expanded into Europe around 400,000 years ago. Until their extinction about 40,000 years ago, they expanded their range across Europe, Western Asia, Central Asia, and even the Altai Mountains in Siberia. It is becoming clear that Neanderthals possessed high intelligence and adaptability, such as ingesting painkilling compounds and using pigments.

The site excavated by the research group this time was Üçağızlı II Cave in southern Türkiye, which forms the northern edge of the Levant region through which modern humans passed during their Out-of-Africa migration. Excavations began in 2021, carefully digging through an area of about 20 square meters millimeter by millimeter. While digging through 30 centimeters of geological strata (dating from approximately 47,000 to 77,000 years ago), they discovered three modern humans and two Neanderthals. Because these human fossil remains included teeth, a body part allowing high-precision species identification based on anatomical features, the human species could be definitively identified.

In addition, 24,236 animal bone fossils that had been consumed, 59 inedible seashells, and 19,252 stone tools were found. Among the inedible shells, 29 were C. rustica shells, six of which had holes and were believed to have been used as beads. These artifacts revealed that Neanderthals and modern humans at that time shared the same culture.

Morimoto noted, "There may have been some form of interaction between the two groups." The research team plans to continue their excavation work. An exhibition regarding this excavation is being held at the National Museum of Nature and Science (Taito City, Tokyo Prefecture) through September 6.

Journal Information
Publication: PNAS
Title: Long-term cultural continuity across the Neanderthal-modern human sequence at Üçağızlı II Cave, northern Levant
DOI: 10.1073/pnas.2609061123