We have developed an artificial chemistry that allows selfmaintaining molecular systems to mutate and exhibit innovative behaviour. The molecular species in the chemistry are defined by strings of symbols that specify both the binding affinity and the reaction. We define a replicase molecule that can copy any other molecule that binds at a particular region on the replicase. Molecules are copied on a symbol-by-symbol basis. Occasional mis-copying of an individual symbol forms our mutation scheme. This paper describes the characteristics of the resulting evolutionary system. We ran 1,000 open-ended trials and observed an unexpectedly wide range of emergent phenomena, with many parallels to biological systems. We report these phenomena in qualitative terms, and give details of one of the most interesting among them: the emergence of co-dependent replicase hypercycles.
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@inproceedings(SS-ALife12-plazzmid, author = "Simon Hickinbotham and Edward Clark and Susan Stepney and Tim Clarke and Adam Nellis and Mungo Pay and Peter Young", title = "Diversity from a monoculture: effects of mutation-on-copy in a string-based artificial chemistry", pages = "24-31", crossref = "ALife12" ) @proceedings(ALife12, title = "ALife XII, Odense, Denmark, August 2010", booktitle = "ALife XII, Odense, Denmark, August 2010", publisher = "MIT Press", year = 2010 )