Towards a Framework for Observing Artificial Life Forms

Evolutionary processes have emerged as the defining feature of "life" in artificial life (Alife). When studying the behavior of a particular Alife form, the question naturally arises, whether a particular run of an Alife experiment exhibits evolutionary behavior or not. This paper presents the observer framework, a formal framework for answering this question, based upon the notion of observations made in the Alife model at hand. Starting with defining entities and their relationships observed during the runs, the framework prescribes a series of definitions (decisions) that the observer of the Alife form needs to make, followed by axioms (conditions) that must be met in order to establish evolutionary behavior in particular runs. We use the example of cellular automata based Langton loops to illustrate the observer framework, and suggest directions for further Alife research, based upon the framework design and the case study analysis.