COMMUNICATIONS BIOLOGY ARTICLE DOI: 10.1038/s42003.018-0078.7 OPEN Construction of arbitrarily strong amplifiers of natural selection using evolutionary graph theory Andreas Pavlogiannisl, Josef Tkadlecl, Krishnendu Chatterjeel & Martin A. Nowaku 2 Because of the intrinsic randomness of the evolutionary process, a mutant with a fitness advantage has some chance to be selected but no certainty. Any experiment that searches for advantageous mutants will lose many of them due to random drift. It is therefore of great interest to find population structures that improve the odds of advantageous mutants. Such structures are called amplifiers of natural selection: they increase the probability that advantageous mutants are selected. Arbitrarily strong amplifiers guarantee the selection of advantageous mutants, even for very small fitness advantage. Despite intensive research over the past decade, arbitrarily strong amplifiers have remained rare. Here we show how to construct a large variety of them. Our amplifiers are so simple that they could be useful in biotechnology, when optimizing biological molecules, or as a diagnostic tool, when searching for faster dividing cells or viruses. They could also occur in natural population structures. 1IST Austria, A-3400 Klosterneuburg. Austria. 2 Program for Evolutionary Dynamics. Department of Organismic and Evolutionary Biology, Department of Mathematics, Harvard University, Cambridge, MA 02138, USA. These authors contributed equally: Andreas Pavlogiannis, Josef Tkadlec. Correspondence and requests for materials should be addressed to M.A.N. (email: martin_noviak@han•ard.edu) COMMUNICAIIONS BIOLOGY I (2018)1:71100110.1038/542003.016.0078.7 I wiwynalurecornkommsbto 1 EFTA00811287