Fig. 3

Population structure of Staphylococcus aureus complex. a The population memberships of the inspected species for a priori defined number of clusters K = 2–4 inferred by the Structure software. Each individual is represented by a thin vertical line divided into K colored segments that represent the individual’s estimated membership fractions in K clusters. Populations are labeled below the figure. b The detection of the true number of clusters inferred by the Structure software and set ΔK = mean(|L"(K)|)/ sd(L(K)) as a function of K. ΔK attains its highest value when K = 2