ENKIMDU

As part of an Argonne National Laboratory and University of Chicago initiative, a simulation framework was developed to address many issues in the development of cultures. This simulation framework prototype has been named “ENKIMDU,” after the ancient Sumerian god of agriculture and irrigation. ENKIMDU simulations address natural processes (weather, crop growth, hydrology, soil evolution, population dynamics, etc.) and societal processes (farming and herding practices, kinship-driven behaviors, trade, etc.) interweaving on a daily basis across multi-decadal to multi-generational runs. Software objects representing the salient components of the simulation domain are resolved and modeled at the level of individual persons and households, and individual cropped/fallowed fields, herds, and flocks. This fine temporal resolution and fine granularity in resolving the objects and agents in the simulation domain is essential to our bottom-up modeling approach, with its search for higher-order structure as emergent behavior of an ecology of simpler households.

For the initial phases of our project we have made use of the SWAT model functionality for all of the many physical processes it represents. SWAT is a recently released modeling suite that addresses growth of crops and other vegetation, soil evolution and degradation, moisture and heat exchange with the atmosphere, water and wind erosion, and distributed hydrology. As the project progresses, however, we will need to decompose the SWAT functionality into separate processes that can be accepted or declined individually by the relevant ENKIMDU domain objects, in order to allow project investigators to substitute alternative models/processes to implement domain object dynamic behaviors.

The simulation system includes mechanisms for construction of demographic and household components that are needed to characterize the initial population. This includes the creation of individuals who are in turn members of households, which are subsets of clan and tribal affiliations. During a trial run, ENKIMDU was used to model ancient practices of ancient Mesopotamia. Looking at Medieval and ancient demographic data from the Mediterranean region, we are able to reasonably estimate demographic trends in the pre-industrial Mediterranean world.

Our preliminary pilot study results point to the potential usefulness of the ENKIMDU simulation engine for understanding complex socio-environmental mechanisms that affected the historical and social evolution of ancient Mesopotamia. By explicitly representing dynamics of both societal and natural processes within the same multidisplinary, holistic simulation, ENKIMDU should be able to provide a new level of insights into the behaviors of real-world complex systems.

ENKIMDU is on its way to being able to examine society-scale questions, such as long-term sustainability of settlement systems, as well as issues more relevant at the level of households and individuals. This ability to give highly informative aspects of agency makes ENKIMDU useful for social scientists with varied interests in the components of societies. More importantly, the ability of the simulation chassis to incorporate disparate forms of social theories makes it a potentially useful tool for scholars with different theoretical backgrounds. As we continue to expand ENKIMDU’s capabilities, even more complex agent behaviors can be represented and measured to see their impacts on social change.