The network structure of the urban revolution.

The transportation network during the Uruk Expansion evolved from dendritic river-based systems to a small-world structure with regional clusters and long-distance shortcuts, enhancing connectivity.

• Why it matters: Understanding how early cities maintained extensive connectivity without formal markets or centralized states addresses a fundamental question about the origins of urban networks and social organization.
• What they did: The study assembled the largest spatial dataset of the Uruk Expansion (ca. 3900 to 3000 BCE) and used network analysis to reconstruct transportation networks across three phases, revealing their structural evolution.
• The result: Decentralized interaction processes, supported by mobile intermediary communities, enabled the development of integrated, efficient urban networks with strong local cohesion and system-wide reach.