Fig. 5

Maximum likelihood tree including internal node labels for viable Neisseria gonorrhoeae isolates (n = 191) from 1928 to 2013 dated using least-squares dating (LSD) software v0.3 and 18,779 SNPs, to estimate the rate and the dates of the input phylogeny given temporal constraints. The relationship in the phylogeny shows that the isolates from the postmodern era belonging to the multidrug-resistant clade alone have a most recent common ancestor relatively soon after the inferred emergence of the whole collection, within the late 17th – early eighteenth century