Fig. 6

Rarefaction curves for Mexican ZIKV and Colombian ZIKV. For both Mexico and Colombia, the number of introductions into the country is plotted as a function of the number of genomes sampled from that country, where genomes are subsampled from available sequences. The colored circles show introduction counts for all of the phylogeographically labelled trees; they are sized according to the frequency with which a specific number of introductions was observed for a given level of subsampling. The black line shows the mean number of introductions observed for a given level of subsampling