# Humans 40,000 y ago developed a system of conventional signs

## TL;DR

Forty thousand years ago, humans in Europe used geometric signs on artifacts in a complex and intentional system, similar to early writing.

## Contribution

The study provides the first quantitative analysis of Paleolithic sign sequences, showing their complexity and systematic use.

## Key findings

- Paleolithic sign sequences have statistical properties comparable to early protocuneiform writing.
- Signs were applied more densely on figurines than on tools, indicating intentional use.
- These signs were used in a deliberate and conventional manner, long before the emergence of writing.

## Abstract

Humans have carved visual signs into the surfaces of mobile artifacts and cave walls since several hundred thousand years. We here analyze a 40,000 y old assemblage of mobile artifacts bearing sequences of intentionally engraved geometric signs. These sign sequences have a complexity comparable to the earliest protocuneiform and were selectively applied to yield higher information density on figurines than on tools. This proves that the first hunter-gatherers arriving in Europe already developed a system of intentional and conventional signs on mobile artifacts. Our study more broadly relates to research into statistical properties of human language and writing compared to other sign systems.

As humans, we store and share information. This allows us to distribute knowledge necessary for survival and to coordinate large groups. Our hominin ancestors harnessed the surfaces of mobile artifacts and cave walls as information carriers since the Paleolithic time period. Theories abound as to the meaning and function of these Paleolithic signs. However, very little is known about their basic, measurable properties. We here analyze a corpus of more than 200 mobile objects of a 43,000 to 34,000 y old Aurignacian culture—associated with the first modern humans to settle in Central Europe. These objects are adorned with several thousand geometric signs. We apply classification algorithms and statistical models to capture their quantitative properties. First, our analyses illustrate that these sign sequences are clearly distinguishable from modern day writing. Second, however, their statistical properties are comparable to sign sequences on the earliest protocuneiform tablets. Third, Paleolithic signs were systematically applied to yield higher information density on certain types of objects, e.g. ivory figurines compared to tools. These results cannot be taken to strictly prove that Aurignacian sign sequences encoded numero-ideographic information as in the case of protocuneiform. However, they prove that the first hunter-gatherers arriving in Europe already applied sign sequences of comparable complexity in a deliberate, systematic, and conventional manner—several ten thousand years before the advent of genuine writing.