The Characteristic Time Scale of Cultural Evolution

TL;DR

This study identifies a roughly 2500-year characteristic time scale for the evolution of social complexity across diverse geographic regions, revealing a common lengthy developmental pattern.

Contribution

It introduces a unified logistic regression model to analyze social complexity evolution across multiple regions, highlighting a shared temporal pattern in cultural development.

Findings

A characteristic evolution period of approximately 2500 years.

Similar logistic growth patterns across different geographic areas.

Social complexity evolution involves internal and external influences.

Abstract

Numerous researchers from various disciplines have explored commonalities and divergences in the evolution of complex social formations. Here, we explore whether there is a 'characteristic' time-course for the evolution of social complexity in a handful of different geographic areas. Data from the Seshat: Global History Databank is shifted so that the overlapping time series can be fitted to a single logistic regression model for all 23 geographic areas under consideration. The resulting regression shows convincing out-of-sample predictions and its period of extensive growth in social complexity can be identified via bootstrapping as a time interval of roughly 2500 years. To analyse the endogenous growth of social complexity, each time series is restricted to a central time interval without major disruptions in cultural or institutional continuity and both approaches result in a similar logistic regression curve. Our results suggest that these different areas have indeed experienced a similar course in the their evolution of social complexity, but that this is a lengthy process involving both internal developments and external influences.