Journal of Biomedical Engineering and Medical Devices
Open Access

Digital Organisms

We present a "bestiary" of three digital organisms (self-replicating computer programs) that evolved in three different experimental environments in the Avida platform. The ancestral environments required the evolving organ-isms to use memory in different ways as they gathered information from the environment and made behavioral decisions. Each organism exhibited a behavior or algorithm of particular interest: 1) simple step-counting odometer; 2) clever low-level computation; and 3) pronounced modularity in both program structure and program functionality. We present a descriptive in-depth analysis of the case study organisms, with a focus on the structure and operation of the evolved algorithms that produce the individuals' fitness-enhancing behaviors.