title: Evolution of oil droplets in a chemorobotic platform.
abstract: Evolution, once the preserve of biology, has been widely emulated in software, while physically embodied systems that can evolve have been limited to electronic and robotic devices and have never been artificially implemented in populations of physically interacting chemical entities. Herein we present a liquid-handling robot built with the aim of investigating the properties of oil droplets as a function of composition via an automated evolutionary process. The robot makes the droplets by mixing four different compounds in different ratios and placing them in a Petri dish after which they are recorded using a camera and the behaviour of the droplets analysed using image recognition software to give a fitness value. In separate experiments, the fitness function discriminates based on movement, division and vibration over 21 cycles, giving successive fitness increases. Analysis and theoretical modelling of the data yields fitness landscapes analogous to the genotype-phenotype correlations found in biological evolution.
authors.affiliation: WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Juan Manuel Parrilla
authors.initials: JM
authors.lastname: Gutierrez
authors.affiliation: WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Trevor
authors.initials: T
authors.lastname: Hinkley
authors.affiliation: WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: James Ward
authors.initials: JW
authors.lastname: Taylor
authors.affiliation: Future Bits OpenTech UG, Cologne 51103, Germany.
authors.forename: Kliment
authors.initials: K
authors.lastname: Yanev
authors.affiliation: WestCHEM, School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Leroy
authors.initials: L
authors.lastname: Cronin