From 3500–3000 B.C., the Sumerians of ancient Mesopotamia, in what is now Iraq, carved wedge-shaped signs on clay tablets with reed pens. These are cuneiform, the oldest known writing system. The invention of writing may turn out to be 30,000 years earlier than thought. Signs similar to cuneiform have been identified on Stone Age artifacts unearthed in Germany dating back 40,000 years.
Christian Bentz of Saarland University and Ewa Dutkiewicz of the Museum of Prehistory and Early History in Berlin said on the 24th, local time, in the Proceedings of the National Academy of Sciences (PNAS), that "the order of signs engraved on Stone Age artifacts in Germany has a level of complexity and information density comparable to cuneiform." The meanings of the signs are unknown, but the findings suggest a system capable of carrying information.
◇ Matches the migration period of Homo sapiens
In the 1860s, archaeologists excavated hundreds of tools for making rope and clothing, musical instruments, and hybrid human-animal figurines from caves at the foot of the Swabian Alps in southwestern Germany. All were artifacts made from the tusks and bones of now-extinct animals such as mammoths, cave lions, and cave bears. Bentz said these artifacts, estimated to have been made 43,000 to 34,000 years ago, contain the oldest symbolic precursors of writing known so far.
On 260 artifacts, 22 types of signs were engraved more than 3,000 times. The most frequently used was a V-shaped notch, followed by lines, crosses, and dots. Y-shaped or star-shaped signs were used less often. Without decisive evidence like the Rosetta Stone, which records Egyptian hieroglyphs alongside ancient Greek, there is currently no way to decipher these signs. Instead, the researchers analyzed the order of the signs. Rather than seeking meanings, they tested whether the signs had the complexity of a script sufficient to carry information.
The researchers used computers to analyze the complexity and information density of the sign sequences. They then compared the results with Mesopotamian cuneiform that appeared from 3500–3350 B.C. and with modern scripts. The 40,000-year-old sign sequences were clearly distinguishable from modern writing but similar to proto-cuneiform. Dutkiewicz said, "Humans have long left intentional marks on objects, but the systematic, repeated use of clearly distinct signs as in this case is a completely different order of behavior."
The German artifacts are thought to have been made by groups of Homo sapiens who arrived in Europe about 45,000 years ago. The team said the results suggest that Homo sapiens, Europe's first hunter-gatherers, had already been developing a sign system to record their thoughts 40,000 years ago. Bentz said, "Homo sapiens, the direct ancestors of modern humans, likely possessed the same cognitive abilities as we do today when they left Africa and spread across the world," adding, "It may not be surprising that humanity experimented with communication through writing for so long."
◇ Different signs for humans and animals; may have been a calendar
Cuneiform began in the Mesopotamian civilization, where agriculture developed, as an accounting system to record things like crop yields. So what did Stone Age writing capture? A clue lies in the fact that different signs were used depending on the artifact. The cross was frequently used on artifacts or tools depicting horses or mammoths, but it did not appear on artifacts depicting humans. In contrast, dots were not used on tools at all.
Dutkiewicz described this as "a robust pattern indicating that the signs applied to media were deliberately selected." The cross may not have described humans, and dots may have been used only for living subjects. The meanings are unknown, but the signs may have carried information.
Ben Marwick of the University of Washington's anthropology department told Science the same day that "geometric signs were likely an important information technology," adding, "They would have supported the complex social cooperation needed to hunt large animals such as mammoths." In 2023, a team at Durham University in the United Kingdom argued that dots, lines, and Y-shaped signs placed in sequences next to animal drawings in 20,000-year-old European caves were codes recording prey behavior.
The team also suggested the signs carved on the German artifacts may have been a calendar. For example, a lion-human hybrid carved from mammoth ivory is engraved with dots and notches arranged in 13 or 12 rows. Dutkiewicz said this may represent calendar observations. It would mean they recorded the 12–13 times the moon waxes and wanes in a year with signs. A calendar would have been essential for tracking when prey migrated.
So why didn't the hunters' signs in the Swabian region develop into a full writing system? Marwick said society at the time likely did not need writing that sophisticated. Hunter-gatherers then had systems that perfectly met their needs, and they felt no pressure to change them. By contrast, in much later agricultural societies, population boomed and commerce developed, and official scripts were likely needed to maintain complex societies.
References
PNAS (2026), DOI: https://doi.org/10.1073/pnas.2520385123
Cambridge Archaeological Journal (2023), DOI: https://doi.org/10.1017/S0959774322000415