Consumption patterns in prehistoric Europe are consistent with modern economic behaviour

Have humans always sold and purchased things? This seemingly trivial question exposes one of the most conspicuous blind spots in our understanding of cultural evolution: the emergence of what we perceive today as 'modern' economic behaviour. Here we test the hypothesis that consumption patterns in prehistoric Europe (around 2300-800 BCE) can be explained by standard economic theory, predicting that everyday expenses are log-normally distributed and correlated to supply, demand and income. On the basis of a large database of metal objects spanning northern and southern Europe (n = 23,711), we identify metal fragments as money, address them as proxies of consumption and observe that, starting around 1500 BCE, their mass values become log-normally distributed. We simulate two alternative scenarios and show that: (1) random behaviour cannot produce the distributions observed in the archaeological data and (2) modern economic behaviour provides the best-fitting model for prehistoric consumption.