This paper presents an approach to the design of a collection of competing, autonomous robots which evolve. Robots live in an environment similar to a Skipper Computer Zoo, and compete with each other for access to one or more energy sources. A computer zoo is a complete electronic ecosystem populated by digital creatures which exhibit some of the behaviors of animals. A digital creature is a computer program. The Computer Zoo provides a good framework for investigating the effects of competition between artificial life forms. The contribution of this research is the design of a collection of evolving behavioral competences in the guise of hunter and prey robots living together and competing with each other in a bounded universe.