a, Inference of population structure using STRUCTURE on S. paradoxus (markers: 7544 SNPs with >30 strains passing neighbourhood quality standard, NQS), assuming K=6 subpopulations and correlated allele frequencies, linkage model based on marker distances in basepairs, 15000 iteration burn in, and 5000 iterations of sampling. Each mark on the x axis represents one strain, and the blocks of colour represent the fraction of the genetic material in each strain assigned to each cluster.
b, As a, but for S. cerevisiae (markers: 3413 SNPs with >30 strains passing NQS)