Title: Who Needs Genomes? Authors: Barry McMullin, Dublin City University Tim Taylor, University of Abertay Dundee Axel von Kamp, Dublin City University Abstract: The first abstract but detailed mechanistic models for genetically based reproduction were developed by John von Neumann in the period 1948-1953. Subsequent elaboration of the structure and function of DNA proved von Neumann's designs to have been strikingly prescient. However, some significant questions still remain as to the specific benefits of this particular reproductive architecture. These questions are relevant both to understanding the evolutionary emergence of such systems, and their proper role in engineered or synthetic evolutionary systems. This paper will review these issues, and present some preliminary results of novel evolutionary experiments in the Tierra system, where artificial "organisms" are deliberately engineered to have an *evolvable* genetic architecture.