We illustrate how co-evolutionary experiments involving simulated predator and prey robots can lead to long-term global progress, i.e. can produce robots displaying progressively better performance against both competitors of current and previous generations. This is obtained by exposing evolving robots to well-differentiated competitors, by preserving individuals displaying good performance against hard to handle competitors, and by discarding opportunistic individuals that perform poorly against the other competitors of the current generation. The accumulation of variations producing general progress for more than 50,000 generations leads to the evolution of sophisticated behavioral capabilities and enable evolved robots to outperform robots evolved with simpler methods.
