Microcosms is a multi-agent simulation framework developed in Squeak (Smalltalk) that allows the creation of virtual systems. The framework is used to study emergent phenomena in complex systems.
This project began as a final exercises of a course (Programing Simulation models in Smalltalk) held at the University of Buenos Aires. Then the framework was used (and is still used) to explore some ideas about ecological system dynamics.
These activities allowed us to interact with György Szabó, who was interested in the patterns observed. Some results were published (Szabó G and G. Sznaider. 2004. "Phase transition and selection in a four-species cyclic Lotka-Volterra model".. Physical. Review E 69, 031911)
An introductory demo and a download link of the whole system could be found here
More information could be found in the course home page