The ESP method for evolving virtual creatures [1] consisted of an encapsulation mechanism to preserve learned skills, a human-designed syllabus to build higher-level skills by combining lower-level skills systematically, and a pandemonium mechanism to resolve conflicts between encapsulated skills in a single creature's brain. Previous work with ESP showed that it is possible to evolve much more complex behavior than before, even when fundamental morphology (i.e., skeletal segments and joints) was evolved only for the first skill. This paper introduces a more general form of ESP in which full morphological development can continue beyond the first skill, allowing creatures to adapt their morphology to multiple tasks. This extension increases the variety and quality of evolved creature results significantly, while maintaining the original ESP system's ability to incrementally develop complex behaviors from a sequence of simpler learning tasks. In the future, this method should make it possible to build EVCs with complex and believable behavior.

[1] Dan Lessin, Don Fussell, and Risto Miikkulainen. Open-Ended Behavioral Complexity for Evolved Virtual Creatures. GECCO 2013.