The objective of the work reported here is to create the conditions under which there can be a spontaneous increase in complexity of digital replicators. The study focuses on complexity in the sense of differentiation of the threads of multi-threaded processes into different ``cell types'', where different cell types are different threads that execute different code.
I believe that evolution can only generate great increases of complexity in the context of an evolving ecological community, as biotic evolutionary interactions are an important driving force in evolution. It appears that this is what happened in organic evolution. Life transforms the environment, such that the living component of the environment comes to predominate over the physical environment, after which most evolution involves adaptations to other living organisms. Thus the complexity of the living component of the environment comes to greatly exceed the complexity of the physical environment that it is embedded in.