design: Genomic DNA was extracted for the ancestral strain (AN) and a single clonal isolate from each evolved population (S1-S10) using QIAamp DNA Blood Midi Kit (Qiagen) following the manufacturers recommendations from 50 mL culture incubated at 17 C for 5 days in 75 cm2 flasks. The Qubit (Invitrogen) quantification ranged between ~3 g and 13 g of genomic DNA in total. All of the subsequent steps were performed by the CRG Genomics Unit (Barcelona): sequencing libraries were prepared using from the pure high molecular weight DNA using TruSeq DNA HT Library Preparation kit (Illumina  HiSeq  Sequencing v4 Chemistry). A paired-end library with a target insert size of ~500 bp was sequenced on an Illumina HiSeq2500 platform in paired-end mode, with read lengths of 125 bp.