It is not difficult to come up with ways in which settlements of the past were different from contemporary cities. What is harder to do, but much more interesting, is identify ways in which they were the same. In a recent post on the Urban Studies Journal blog, Social Reactors Project researcher Scott Ortman argues that one of the most important properties they share are scaling relationships between their populations, densities, infrastructural quantities, and economic productivities. Ortman also shares the back story behind these discoveries. The post was written to accompany the recent publication by Jose Lobo and the Social Reactors Project team in Urban Studies, the leading international journal for urban scholarship. You can read the paper here.